Patent Description:
Abrasive wheels are typically used for cutting, abrading, and shaping of various materials, such as stone, metal, glass, plastics, among other materials. Generally, the abrasive wheels can have various phases of materials including abrasive grains, a bonding agent, and some porosity. Depending upon the intended application, the abrasive wheel can have various designs and configurations. For example, for applications directed to the finishing and cutting of metals, some abrasive wheels are fashioned such that they have a particularly thin profile for efficient cutting.

However, given the application of such wheels, the abrasive articles are subject to fatigue and failure. In fact, the wheels may have a limited time of use of less than a day depending upon the frequency of use. Accordingly, the industry continues to demand abrasive wheels capable of improved performance. <CIT> discloses an abrasive cutting tool, according to the preamble of claim <NUM>.

So that the manner in which the features and advantages of the embodiments are attained and can be understood in more detail, a more particular description may be had by reference to the embodiments thereof that are illustrated in the appended drawings. However, the drawings illustrate only some embodiments and therefore are not to be considered limiting in scope as there may be other equally effective embodiments.

Preferred embodiments are defined in the dependent claims respectively. The following is directed to abrasive tools having abrasive particles contained within a bond material for cutting workpieces. Certain embodiments herein are directed to bonded abrasive wheels, including cut off wheels, which may be used for cutting metal workpieces, including metals of titanium or stainless steel. However, the features of the embodiments herein may be applicable to other abrasive technologies, including for example, coated abrasives and the like.

The abrasive article can be made by forming a mixture of components or precursor components that may be part of the final abrasive article. For example, the mixture can include components of the final abrasive article, such as abrasive particles, bond material, filler, and a combination thereof. In one embodiment, the mixture can include a first type of abrasive particle. A type of abrasive particle can be defined by at least a composition, a mechanical property (e.g., hardness, friability, etc.), particle size, a method of making, and a combination thereof.

The abrasive tools may utilize abrasive portions of abrasive grains contained within a matrix material for cutting, abrading, and finishing of workpieces. Certain embodiments herein are directed to large-diameter abrasive wheels incorporating one or more reinforcing members within the body of the tool that are particularly suited for cutting and/or shaping metal.

<FIG> includes an illustration of an abrasive tool in accordance with an embodiment. Notably, the abrasive tool <NUM> includes a body <NUM> having a generally circular shape as viewed in two dimensions. It will be appreciated, that in three-dimensions the tool has a certain thickness such that the body <NUM> has a disk-like or a cylindrical shape. As illustrated, the body can have an outer diameter <NUM> extending through the center of the tool, which can be particularly large, having a dimension of at least about <NUM>. In other applications, the body <NUM> can have an outer diameter <NUM>, such as on the order of at least about <NUM> centimeters, at least about <NUM> centimeters, or even at least <NUM> centimeters. Particular abrasive tools utilize a body <NUM> having an outer diameter <NUM> within a range between <NUM> centimeters and about <NUM> centimeters, such as between <NUM> and about <NUM>, and more particularly between about <NUM> centimeters and about <NUM> centimeters.

As further illustrated, the abrasive tool <NUM> can include a central opening <NUM> defined by an inner circular surface <NUM> about the center of the body <NUM>. The central opening <NUM> can extend through the entire thickness of the body <NUM> such that the abrasive tool <NUM> can be mounted on a spindle or other machine for rotation of the abrasive tool <NUM> during operation.

<FIG> includes a cross-sectional illustration of a portion of an abrasive tool in accordance with an embodiment. The abrasive body <NUM> can be a composite article including a combination of portions of different types of material. In particular, the body <NUM> can include abrasive portions <NUM>, <NUM>, <NUM>, and <NUM> and reinforcing members <NUM>, <NUM>, and <NUM>. The abrasive tool <NUM> can be designed such that the reinforcing members <NUM>, <NUM>, and <NUM> can be placed within the body such that they are spaced apart from each other, and therein, separate each of the abrasive portions <NUM>, <NUM>, <NUM>, and <NUM> from each other. That is, the abrasive tool <NUM> can be formed such that the reinforcing members <NUM>, <NUM>, and <NUM> are spaced apart from each other laterally through the thickness <NUM> of the body <NUM> and separated by abrasive portions <NUM> and <NUM>. As will be appreciated, in such a design the abrasive portions <NUM> and <NUM> can be disposed between the reinforcing members <NUM>, <NUM>, and <NUM>.

As further illustrated, the reinforcing members <NUM>, <NUM>, and <NUM> can be substantially planar members having first planar faces and second planar faces. For example, the reinforcing member <NUM> can be formed such that it is a planar member having a first major surface <NUM> and a second major surface <NUM>. Moreover, the body <NUM> can have a design such that the abrasive portions <NUM>, <NUM>, <NUM>, and <NUM> can overlie the major surface of the reinforcing members <NUM>, <NUM>, and <NUM>. For example, the abrasive portion <NUM> can overlie the first major surface <NUM> of the reinforcing member <NUM> and the abrasive portion <NUM> overlies the second major surface <NUM> of the reinforcing member <NUM>. In particular instances, the body <NUM> can be formed such that the abrasive portions <NUM> and <NUM> cover essentially the entire surface area of the first major surface <NUM> and second major surface <NUM>, respectively. Accordingly, the abrasive portions <NUM> and <NUM> can directly contact (i.e. abut) the reinforcing member <NUM> on either sides at the first and second major surfaces <NUM> and <NUM>.

Notably, the abrasive body <NUM> can be designed such that the reinforcing members <NUM>, <NUM>, and <NUM> can extend through a majority of the diameter <NUM> of the body <NUM>. In particular instances, the reinforcing members <NUM>, <NUM>, and <NUM> can be formed such that they extend through at least about <NUM>%, such as at least about <NUM>%, or even the entire diameter <NUM> of the body <NUM>.

In accordance with an embodiment, the body <NUM> is formed such that it can have an average thickness <NUM> measured in a direction parallel to the axial axis <NUM> extending through the center of the central opening <NUM>. The average thickness <NUM> of the body <NUM> can be particularly thin such that it is suitable for cutting metal workpieces. For example, the average thickness of the body <NUM> can be not greater than about <NUM> centimeters. In other embodiments, the average thickness <NUM> of the body <NUM> can be not greater than about <NUM> centimeters, such as not greater than about <NUM> centimeters, or even not greater than about <NUM> centimeters. Still, certain embodiments may utilize an average thickness <NUM> within a range between about <NUM> centimeters and about <NUM> centimeters, such as between about <NUM> centimeters and about <NUM> centimeters.

The disk has an aspect ratio defined as a ratio (D:T) between the outer diameter <NUM> to an axial thickness <NUM> of the body. The ratio (D:T) is at least about <NUM>:<NUM>, such as at least about <NUM>:<NUM>, at least about <NUM>:<NUM>, or even at least about <NUM>:<NUM>. Certain embodiments utilize an aspect ratio within a range between about <NUM>:<NUM> and about <NUM>:<NUM>, such as between about <NUM>:<NUM> and about <NUM>:<NUM>.

In further reference to the reinforcing members <NUM>, <NUM>, and <NUM>, such members can be made of an organic material, inorganic material, and a combination thereof. For example, the reinforcing members <NUM>, <NUM>, and <NUM> can be made of an inorganic material, such as a ceramic, a glass, quartz, or a combination thereof. Particularly suitable materials for use as the reinforcing members <NUM>, <NUM>, and <NUM> can include glass materials, incorporating fibers of glass materials, which may include oxide-based glass materials.

Some suitable organic materials for use in the reinforcing members <NUM>, <NUM>, and <NUM> can include phenolic resin, polyimides, polyamides, polyesters, aramids, and a combination thereof. For example, in one particular embodiment, the reinforcing members <NUM>, <NUM>, and <NUM> can include Kevlar™, a particular type of aramid.

Additionally, the reinforcing members <NUM>, <NUM>, and <NUM> can include a fibrous material having a coating overlying and bonded directly to the external surfaces of the fibers. The coating can be an organic material, inorganic material, or a combination thereof. Certain abrasive tools can use reinforcing members <NUM>, <NUM>, and <NUM> utilizing fibers having a coating of an organic material, which may be a natural organic material or a synthetic organic material, such as a polymer, which may aid bonding between the reinforcing member and the abrasive portion. Some suitable organic coating materials can include resins, which may be thermosets, thermoplastics, or a combination thereof. Particularly suitable resins can include phenolics, epoxies, polyesters, cyanate esters, shellacs, polyurethanes, and a combination thereof. In one particular instance, the abrasive tool incorporates a reinforcing member comprising phenolic resin-coated glass fibers.

The reinforcing members <NUM>, <NUM>, and <NUM> can include a plurality of fibers that are woven together. The fibers can be woven or stitched together in a variety of manners. In certain instances, the reinforcing members can be woven together such that a pattern is formed, including fibers extending primarily in two perpendicular directions.

The reinforcing members <NUM>, <NUM>, and <NUM> can have an average thickness <NUM> that is defined as the distance between the first major surface <NUM> and the second major surface <NUM> of the reinforcing member <NUM>. The average thickness <NUM> can be at least about <NUM>, at least about <NUM>, at least about <NUM>, at least about <NUM>. Alternatively, the average thickness <NUM> can be not greater than about <NUM>, not greater than about <NUM>, or even not greater than about <NUM>. It will be appreciated that the reinforcing member may have a thickness within a range between any of the above-noted minimum and maximum values.

In relative percentages, depending upon the design of the abrasive article, the reinforcing members can be formed to have certain dimensions such that they compose a certain percentage of the total average thickness of the body. For example, the reinforcing member <NUM> can have an average thickness <NUM> that is at least about <NUM>% of the total average thickness <NUM> of the body <NUM>. In other instances, the reinforcing member <NUM> can have an average thickness <NUM> that is at least about <NUM>%, such as at least about <NUM>%, or even at least about <NUM>% of the total average thickness <NUM> of the body <NUM>. Alternatively, the average thickness of the body can be not greater than about <NUM>%, not greater than about <NUM>%, or even not greater than about <NUM>% of the total average thickness <NUM> of the body <NUM>. Certain reinforcing members can have an average thickness <NUM> that is within a range between about <NUM>% and about <NUM>% of the total average thickness <NUM> of the body <NUM>. It will be appreciated that the reinforcing member may have a thickness within a range between any of the above-noted minimum and maximum values.

In accordance with embodiments herein, the abrasive tool <NUM> is formed such that the body <NUM> includes abrasive portions <NUM>, <NUM>, <NUM>, and <NUM>. Reference will be made in the following paragraphs to the abrasive portion <NUM>, however it will be appreciated that all of the identified abrasive portions can include the same features. The abrasive portion <NUM> can be a composite material having abrasive grains contained within a matrix material and further comprising a particular composition and type of porosity.

The abrasive grains can include a particularly hard material suitable for abrading and material removal applications. For example, the abrasive grains can have a Vickers hardness of at least about <NUM> GPa. The hardness of the abrasive grains can be greater in some tools, such that the abrasive grains have a Vickers hardness of at least about <NUM> GPa, at least about <NUM> GPa, at least about <NUM> GPa, or even at least about <NUM> GPa. It will be appreciated that the abrasive grains may have a hardness within a range between any of the above-noted minimum and maximum values.

As further illustrated in <FIG>, the body is formed such that it incorporates reinforcing members <NUM> and <NUM> that abut the outer surfaces of the abrasive portions <NUM> and <NUM> about the central opening <NUM>. In certain designs, the reinforcing members <NUM> and <NUM> can extend for a portion of the outer diameter <NUM>, such as half the outer diameter <NUM> of the abrasive body <NUM>. Provision of the reinforcing members <NUM> and <NUM> about the central opening <NUM> facilitates reinforcement of the body <NUM> at a location where the abrasive tool <NUM> is intended to be affixed to a spindle or machine. As will be appreciated, the reinforcing members <NUM> and <NUM> can have the same features as the reinforcing members <NUM>, <NUM>, and <NUM>.

According to the present invention, the reinforcing member comprises not greater than about <NUM> vol% of a total volume of the body, not greater than about <NUM> vol% not greater than about <NUM> vol%; at least about <NUM> vol%, at least about <NUM> vol%, at least about <NUM> vol%. It will be appreciated that the reinforcing member may comprise a volume within a range between any of the above-noted minimum and maximum values.

In still other embodiments, a volumetric ratio VR of the abrasive portion to the reinforcing member is at least about <NUM>, where VR = (volume of reinforcing member)/(volume of abrasive portion). In some versions, VR is at least about <NUM>, at least about <NUM>, not greater than about <NUM>, not greater than about <NUM>, or even not greater than about <NUM>. It will be appreciated that the reinforcing member may comprise a volumetric ratio within a range between any of the above-noted minimum and maximum values.

The reinforcing member comprises an opening that defines an open area of at least about <NUM><NUM> within a major plane of the reinforcing member; and the opening defines an open area of not greater than about <NUM><NUM> within a major plane of the reinforcing member.

In addition, Differential Scanning Calorimetry (DSC) measures the temperatures and heat flows associated with transitions in materials as a function of time and temperature in a controlled atmosphere. These measurements provide quantitative and qualitative information about physical and chemical changes that involve endothermic or exothermic processes, or changes in heat capacity. DSC may be measured using an approximately <NUM> sample of fiberglass in a nitrogen environment. The sample may be ramped to <NUM> at a ramp of <NUM>/min and held for <NUM> minutes. For example, the reinforcing member may comprise a DSC enthalpy of reaction less than about <NUM> J/g, less than about <NUM> J/g, less than about <NUM> J/g, less than about <NUM> J/g. It will be appreciated that the reinforcing member may comprise a value within a range between any of the above-noted minimum and maximum values.

In other embodiments, the reinforcing member may comprise a DSC enthalpy of crystallization of less than about <NUM> J/g, less than about <NUM> J/g, less than about <NUM> J/g, less than about <NUM> J/g, less than about <NUM> J/g, less than about <NUM> J/g, less than about <NUM> J/g. It will be appreciated that the reinforcing member may comprise a value within a range between any of the above-noted minimum and maximum values.

<FIG> includes a cross-sectional illustration of a portion of an abrasive tool in accordance with an embodiment. The portion of the illustrated abrasive tool <NUM> includes an outer circumference of an abrasive tool formed in accordance with an embodiment. Particularly, the portion of the abrasive tool <NUM> can have a body <NUM> including abrasive portions <NUM>, <NUM>, <NUM>, and <NUM> previously described. Moreover, the abrasive body <NUM> includes reinforcing members <NUM>, <NUM>, and <NUM> disposed between the abrasive portions <NUM>, <NUM>, <NUM>, and <NUM> as previously described.

Notably, the body <NUM> is formed such that it has a flat region <NUM> proximate to the center of the wheel and surrounding the central opening <NUM>, and a tapered region <NUM> at the outer edge of the body <NUM>. As illustrated, the tapered region <NUM> is formed such that it has an average thickness <NUM> measured at the outer diameter of the body <NUM> that is significantly greater than the average thickness <NUM> of the body <NUM> within the flat region <NUM>. The formation of the tapered region <NUM> is facilitated by the extension of a tapered edge <NUM> of the abrasive portion <NUM> that extends at an angle to the external surface308 of the flat region <NUM> of the abrasive portion <NUM>. The tapered region <NUM> is further defined by a tapered surface <NUM> of the abrasive portion <NUM>, which extends at an angle to the surfaces <NUM> of the abrasive portion <NUM>. As illustrated, the tapered region <NUM> can form a rim around the outer diameter of the wheel, wherein the tapered surfaces <NUM> and <NUM> extend at an angle axially outward from the surfaces <NUM> and <NUM>, respectively. The tapered surfaces <NUM> and <NUM> can extend at an angle to a radius extending from the center of the body substantially parallel to the surfaces <NUM> and <NUM>, and moreover, the tapered surfaces <NUM> and <NUM> can extend at an angle to an axial axis <NUM> extending through the center of the body <NUM>.

According to some embodiments, the tapered region <NUM> can extend circumferentially around a portion of a periphery of the body <NUM>. Certain designs may utilize a tapered region <NUM> that extends throughout the entire circumference of the body <NUM>. While reference is made herein to abrasive articles incorporating a tapered region <NUM>, it will be appreciated, that a tapered region <NUM> may not necessarily be present for certain abrasive articles.

As illustrated, the tapered region <NUM> can extend radially from the flat region <NUM> of the body <NUM>. Embodiments herein may form a tapered region <NUM> having a length <NUM>, as measured in a direction parallel to a radius extending from the center of the body <NUM>, which can be a particular percentage of the dimension of the outer diameter <NUM> of the body <NUM>. For example, the tapered region <NUM> can have a length <NUM> that is at least about <NUM>% of the dimension of the outer diameter <NUM>. In other cases, depending upon the intended application, the body <NUM> can have a tapered region <NUM> having a length <NUM> of at least about <NUM>%, such as at least about <NUM>%, at least about <NUM>%, at least about <NUM>%, or even at least about <NUM>%, of the dimension of the outer diameter <NUM>. Particular embodiments can utilize a tapered region <NUM> wherein the length <NUM> is within a range between about <NUM>% and about <NUM>%, and particularly between about <NUM>% and about <NUM>%, or even more particularly between about <NUM>% and about <NUM>% of the outer diameter <NUM>.

In other terms, the length <NUM> of the tapered region can be at least about <NUM> centimeters. In some embodiments, the length <NUM> of the tapered region <NUM> can be greater, such as at least about <NUM> centimeters, at least about <NUM> centimeters, or even at least about <NUM> centimeters. Still, particular embodiments herein can utilize a tapered region <NUM> having a length <NUM> within a range between about <NUM> centimeters and about <NUM> centimeters, such as between about <NUM> centimeters and about <NUM> centimeters.

The abrasive portion may comprise a filler contained within the abrasive portion. The filler may comprise a first filler comprising iron and sulfur. The first filler may comprise pyrite (FeS<NUM>). Alternatively, the first filler may consist essentially of pyrite.

In a particular embodiment, the first filler may comprise at least about <NUM> vol% of a total volume of the fillers within the abrasive portion. In certain instances, the filler content may be greater, such as at least about <NUM> vol%, or even at least about <NUM> vol%. In another non-limiting embodiment, the filler content can be not greater than about <NUM> vol% of the total volume of the fillers within the abrasive portion, such as not greater than about <NUM> vol%, or even not greater than about <NUM> vol%. The abrasive portion can have a first filler content within a range between any of the minimum and maximum percentages noted above.

In some embodiments, the average particle size of the first filler can be not greater than about <NUM> microns. In some examples, the average particle size of the first filler can be not greater than about <NUM> microns, such as not greater than about <NUM> microns, not greater than about <NUM> microns, not greater than about <NUM> microns, or even not greater than about <NUM> microns. In other non-limiting embodiments, the first filler can have an average particle size of at least about <NUM> micron, such as at least about <NUM> microns, or even at least about <NUM> microns. The average particle size of the first filler can be within a range between any of the minimum and maximum values noted above.

In other embodiments, the abrasive portion may comprise a second filler. The second filler may comprise potassium. The second filler may further comprise aluminum, fluoride or a combination thereof. For example, the second filler may comprise a compound including potassium, aluminum, and fluoride. In one particular instance, the second filler may consist essentially of KAlF<NUM>.

In some embodiments, the abrasive portion may comprise a greater content of the first filler (vol%) as compared to a content of the second filler (vol%). The abrasive portion may comprise a ratio (V1/V2) of at least about <NUM>, wherein V1 represents a content of the first filler (vol%) within the abrasive portion and V2 represents a content of the second filler (vol%) within the abrasive portion. In other examples, the ratio (V1/V2) may be at least about <NUM>, or even at least about <NUM>. In other non-limiting embodiments, the ratio (V1/V2) may be not greater than about <NUM>, such as not greater than about <NUM>, not greater than about <NUM>, or even not greater than about <NUM>, or even not greater than about <NUM>. The ratio (V1/V2) can be within a range between any of the minimum and maximum values noted above.

In a particular embodiment, the second filler can be at least about <NUM> vol% of a total volume of the fillers. For example, the second filler can be at least about <NUM> vol% of the total volume of the fillers, such as at least about <NUM> vol%, or even at least about <NUM> vol%. In certain non-limiting examples, the second filler can be not greater than about <NUM> vol% of the total volume of the fillers, such as not greater than about <NUM> vol%, or even not greater than about <NUM> vol%. The second filler content can be within a range between any of the minimum and maximum values noted above.

In some instances, the second filler may comprise an average particle size of not greater than about <NUM> microns. For example, the average particle size of the second filler can be not greater than about <NUM> microns, such as not greater than about <NUM> microns, or even not greater than about <NUM> microns. In other non-limiting embodiments, the average particle size of the second filler can be at least about <NUM> microns, such as at least about <NUM> microns, or even at least about <NUM> microns. The second filler average particle size can be within a range between any of the minimum and maximum values noted above.

In other embodiments, the abrasive portion may comprise a third filler different than the first filler. The third filler may comprise calcium. The third filler may further comprise oxygen, or a compound including calcium and oxygen. The third filler may consist essentially of CaO.

Examples of the third filler may comprise an average particle size of not greater than about <NUM> microns. In particular instances, the third filler average particle size can be not greater than about <NUM> microns, such as not greater than about <NUM> microns. Non-limiting embodiments may include a third filler having an average particle size of at least about <NUM> microns, such as at least about <NUM> microns, or even at least about <NUM> microns. The third filler average particle size can be within a range between any of the minimum and maximum values noted above.

The abrasive portion also may comprise a greater content of the first filler (vol%) as compared to the content of the third filler (vol%). The abrasive portion may comprise a ratio (V1/V3) of at least about <NUM>, wherein V1 represents a content of the first filler (vol%) within the abrasive portion, and V3 represents a content of the third filler (vol%) within the abrasive portion. In other examples the ratio (V1/V3) may be at least about <NUM>, such as at least about <NUM>, at least about <NUM>, at least about <NUM>, or even at least about <NUM>. In other non-limiting embodiments, the ratio (V1/V3) can be not greater than about <NUM>, such as not greater than about <NUM>, not greater than about <NUM>, not greater than about <NUM>, or even not greater than about <NUM>. The ratio (V1/V3) can be within a range between any of the minimum and maximum values noted above.

Still other embodiments of the abrasive portion may comprise a greater content of a second filler (vol%) as compared to a content of the third filler (vol%). The abrasive portion may comprise a ratio (V2/V3) of at least about <NUM>, wherein V2 represents a content of the second filler (vol%) within the abrasive portion and V3 represents a content of the third filler (vol%) within the abrasive portion. In some examples, the ratio (V2/V3) can be at least about <NUM>, at least about <NUM>, at least about <NUM>, or even at least about <NUM>. Non-limiting examples may include the ratio (V2/V3) at not greater than about <NUM>, such as not greater than about <NUM>, not greater than about <NUM>, not greater than about <NUM>, or even not greater than about <NUM>. The ratio (V2/V3) can be within a range between any of the minimum and maximum values noted above.

In a particular embodiment, the third filler can be at least about <NUM> vol% of a total volume of the fillers. In certain instances, the third filler can be greater, such as at least about <NUM> vol%, or even at least about <NUM> vol%. In another non-limiting embodiment, the third filler can be not greater than about <NUM> vol% of the total volume of the fillers, such as not greater than about <NUM> vol%, not greater than about <NUM> vol%, or even not greater than about <NUM> vol%. The fillers can have a third filler content within a range between any of the minimum and maximum values noted above.

In other embodiments, the abrasive portion may comprise a fourth filler. In other examples, the fourth filler may comprise an aggregate including, for example, cement, including more particularly Portland cement, and/or calcium silicates. The fourth filler may comprise thirds by mass of calcium silicates (<NUM> Ca)-SiO2 and <NUM> CaO-SiO2, and the remainder may comprise aluminum and iron containing clinker phases and other compounds. The ratio of CaO to SiO2 may be greater than <NUM>. The magnesium oxide content (MgO) may be less than <NUM>% by mass. In some examples, <NUM>% of the particle size may be lower than <NUM> microns, with an average particle size of about <NUM> microns.

Embodiments of the fourth filler may comprise an average particle size of not greater than about <NUM> microns. For example, the fourth filler average particle size may be not greater than about <NUM> microns, or even not greater than about <NUM> microns. Non-limiting examples of the fourth filler average particle size can be at least about <NUM> micron, such as at least about <NUM> microns, or even least about <NUM> microns. The fourth filler average particle size may be within a range between any of the minimum and maximum values noted above.

Other examples of the abrasive portion may comprise a greater content of the first filler (vol%) as compared to a content of the fourth filler (vol%). The abrasive portion may comprise a ratio (V1/V4) of at least about <NUM>, wherein V1 represents a content of the first filler (vol%) within the abrasive portion and V4 represents a content of the fourth filler (vol%) within the abrasive portion. Alternatively, the ratio (V1/V4) can be at least about <NUM>, such as at least about <NUM>, at least about <NUM>, at least about <NUM>, or even at least about <NUM>. Other non-limiting embodiments of the ratio (V1/V4) can be not greater than about <NUM>, such as not greater than about <NUM>, not greater than about <NUM>, or even not greater than about <NUM>. The ratio (V1/V4) can be within a range between any of the minimum and maximum values noted above.

Examples of the abrasive portion may comprise a greater content of a second filler (vol%) as compared to a content of the fourth filler (vol%). The abrasive portion may comprise a ratio (V2/V4) of at least about <NUM>, wherein V2 represents a content of the second filler (vol%) within the abrasive portion and V4 represents a content of the fourth filler (vol%) within the abrasive portion. In a particular embodiment, the ratio (V2/V4) can be at least about <NUM>, such as at least about <NUM>. Non-limiting examples of the ratio (V2/V4) can be not greater than about <NUM>, such as not greater than about <NUM>, not greater than about <NUM>, not greater than about <NUM>, or even not greater than about <NUM>. The ratio (V2/V4) can be within a range between any of the minimum and maximum values noted above.

In still another embodiment, the abrasive portion may comprise a greater content of the fourth filler (vol%) as compared to a content of a third filler (vol%). The abrasive portion may comprise substantially the same content (vol%) of the third filler and the fourth filler. The abrasive portion may comprise a ratio (V3/V4) of at least about <NUM>, wherein V3 represents a content of the third filler (vol%) within the abrasive portion and V4 represents a content of the fourth filler (vol%) within the abrasive portion. Other examples of the ratio (V3/V4) can be at least about <NUM>, such as at least about <NUM>, or even at least about <NUM>. Other non-limiting embodiments of the ratio (V3/V4) can be not greater than about <NUM>, such as not greater than about <NUM>, not greater than about <NUM>, or even not greater than about <NUM>. The ratio (V3/V4) can be within a range between any of the minimum and maximum values noted above.

Examples of the abrasive portion may comprise a fourth filler (vol%). For example, the fourth filler can be at least about <NUM> vol% of a total volume of the fillers. Alternatively, the fourth filler can be at least about <NUM> vol% of the total volume of the fillers, such as at least about <NUM> vol%. Non-limiting embodiments of the fourth filler can be not greater than about <NUM> vol% of the total volume of the fillers, such as not greater than about <NUM> vol%, not greater than about <NUM> vol%, or even not greater than about <NUM> vol%. The vol% of the fourth filler in the total volume of the fillers can be within a range between any of the minimum and maximum values noted above.

In other embodiments, the abrasive portion may comprise a combination of the first filler, a second filler, a third filler, and a fourth filler. For example, the abrasive portion may comprise a total content of the first filler, second filler, third filler, and fourth filler of at least about <NUM> vol% for a total volume of the abrasive portion. Alternatively, the total content of the first filler, second filler, third filler, and fourth filler may be at least about <NUM> vol% of the total volume of the abrasive portion, such as at least about <NUM> vol%, at least about <NUM> vol%, or even at least about <NUM> vol%. Non-limiting embodiments may include the total content of the first filler, second filler, third filler, and fourth filler being not greater than about <NUM> vol% of the total volume of the abrasive portion, such as not greater than about <NUM> vol%, or even not greater than about <NUM> vol%. The filler content of the abrasive portion can be within a range between any of the minimum and maximum values noted above.

Embodiments of the abrasive portion also may comprise a wetting liquid remnant in the finished article. For example, the wetting liquid remnant may include an aliphatic chain. The aliphatic chain may be a remnant from tridodecyl alcohol (TDA). In another embodiment, the abrasive portion may comprise a wetting liquid remnant including cyclic organic molecules. The cyclic organic molecules may be a remnant from highly chlorinated wax, furfurol or Chloro <NUM>.

The abrasive portion may comprise at least one wetting liquid, such as those described above, water, castor oil or a combination thereof. In some examples, the bond material may include TDA at at least about <NUM>/lb of bond material, such as at least about <NUM>/lb, or even at least about <NUM>/lb. In other non-limiting examples, the bond material may include TDA at not greater than about <NUM>/lb of bond material, such as not greater than about <NUM>/lb, or even not greater than about <NUM>/lb. The bond material content can be within a range between any of the minimum and maximum values noted above.

In other embodiments, the bond material may include Chloro <NUM> at at least about <NUM>/lb of bond material, such as at least about <NUM>/lb, or even at least about <NUM>/lb. In other non-limiting examples, the bond material may include Chloro <NUM> at not greater than about <NUM>/lb of bond material, such as not greater than about <NUM>/lb, or even not greater than about <NUM>/lb. The bond material content can be within a range between any of the minimum and maximum values noted above.

The body also may comprise a tapered region extending circumferentially around a portion of a periphery of the body. The tapered region may extend through the entire circumference of the body. Alternatively, the tapered region may extend radially from a flat region of the body. In addition, the tapered region of the body may comprise an average thickness that is greater than an average thickness of the flat region of the body. In a particular example, the body may comprise a central opening extending through a thickness of the body.

Some embodiments of the bond material in the abrasive cutting tool can be at least about <NUM> vol% of a total volume of the abrasive portion. For example, the bond material can be at least about <NUM> vol% of the total volume of the abrasive portion, such as at least about <NUM> vol%, or even at least about <NUM> vol%. In non-limiting embodiments, the bond material can be not greater than about <NUM> vol% of the total volume of the abrasive portion, such as not greater than about <NUM> vol%, not greater than about <NUM> vol%, or even not greater than about <NUM> vol%. The bond material content can be within a range between any of the minimum and maximum values noted above.

Embodiments of the body of the abrasive cutting tool may comprise a reinforcing member, such as a first reinforcing member. The first reinforcing member may abut the abrasive portion. The first reinforcing member may be disposed within the abrasive portion. Alternatively, the first reinforcing member may define an external surface of the body. In addition, the first reinforcing member may be disposed internally within the body.

Some embodiments of the first reinforcing member may comprise an organic material. In particular embodiments, the first reinforcing member may comprise a polyimide, polyamide, polyester, aramid, and a combination thereof. Alternatively, the first reinforcing member may comprise an inorganic material. For example, the inorganic material may comprise ceramic materials, glass materials, glass-ceramic materials, or a combination thereof. Alternatively, the first reinforcing member may comprise glass fibers, such as phenolic resin-coated glass fibers.

In still other versions, the first reinforcing member may extend through an entire diameter of the body. The first reinforcing member may comprise a planar member comprising a first major surface and a second major surface. The abrasive portion may overlie the first major surface. Alternatively, the abrasive portion can be in direct contact with the first major surface of the first reinforcing member.

Alternate embodiments of the body of the abrasive cutting tool may comprise a first reinforcing member and a second reinforcing member. The first reinforcing member and the second reinforcing member can be spaced apart from each other within the body. Alternatively, at least a portion of the abrasive portion may be disposed between the first reinforcing member and the second reinforcing member.

In a particular embodiment, the abrasive portion may comprise abrasive grains that may be at least about <NUM> vol% of a total volume of the abrasive portion. In some instances the abrasive grains may be at least about <NUM> vol% of the total volume of the abrasive portion, such as at least about <NUM> vol%, at least about <NUM> vol%, or even at least about <NUM> vol%. In certain non-limiting embodiments, the abrasive grains may be not greater than about <NUM> vol% of the total volume of the abrasive portion, such as not greater than about <NUM> vol%, not greater than about <NUM> vol%, not greater than about <NUM> vol%, or even not greater than about <NUM> vol%. The total volume of the abrasive portion can have an abrasive grain content within a range between any of the minimum and maximum values noted above.

Embodiments of the abrasive particles also may comprise a coating. The coating may comprise, for example, a ceramic, a metal, a transition metal element, iron, an oxide, a metal oxide, or even an iron oxide.

In some embodiments, abrasive portion can include a mixture of more than one type of shaped abrasive particle. For example, the abrasive portion can include a the first type of abrasive particle comprises brown fused alumina (BFA), or may consist essentially of BFA. For example, the first type of particle may comprise Treibacher BFA. BFA may comprise oxides, such as BaO, CaO, Na<NUM>O, P<NUM>O<NUM>, and a combination thereof. For example, BFA may comprise about <NUM> to about <NUM> PPM BaO. BFA also may comprise about <NUM> to about <NUM> PPM CaO. BFA also may comprise about <NUM> to about <NUM> PPM Na<NUM>O. BFA also may comprise less than about <NUM> PPM P<NUM>O<NUM>.

In some examples of the abrasive cutting tool, the BFA may comprise not greater than about <NUM> vol% Al<NUM>O<NUM>. In other examples, the BFA may comprise not greater than about <NUM> vol% Al<NUM>O<NUM>, such as not greater than about <NUM> vol% Al<NUM>O<NUM>. In other non-limiting examples, the BFA may be at least about <NUM> vol% Al<NUM>O<NUM>, such as at least about <NUM> vol% Al<NUM>O<NUM>, or even at least about <NUM> vol% Al<NUM>O<NUM>. The BFA of the abrasive cutting tool can have a Al<NUM>O<NUM> content within a range between any of the minimum and maximum values noted above.

In an alternate embodiment of the abrasive cutting tool, the BFA may comprise not greater than about <NUM> vol% ZrO<NUM>. For example, the BFA may be not greater than about <NUM> vol% ZrO<NUM>, such as not greater than about <NUM> vol% ZrO<NUM>, not greater than about <NUM> vol% ZrO<NUM>, or even not greater than about <NUM> vol% ZrO<NUM>. Other non-limiting embodiments of the BFA may have at least about <NUM> vol% ZrO<NUM>, such as at least about <NUM> vol% ZrO<NUM>, or even at least about <NUM> vol% ZrO<NUM>. The BFA of the abrasive cutting tool can have a ZrO<NUM> content within a range between any of the minimum and maximum values noted above.

In another particular instance, the BFA may have a hardness not greater than about <NUM> GPa. For example, the BFA may have a hardness of not greater than about <NUM> GPa, such as not greater than about <NUM> GPa, or even not greater than about <NUM> GPa. Alternate non-limiting embodiments may include the BFA having a hardness of at least about <NUM> GPa, such as at least about <NUM> GPa, or even at least about <NUM> GPa. The BFA of the abrasive cutting tool can have a hardness within a range between any of the minimum and maximum values noted above.

In an example of a test for hardness, the sample grains are mounted in epoxy and then polished. Once the grains are mounted and polished a desired load is selected on the hardness tester for indentation. The load typically selected is <NUM>, but a load of <NUM> also may be selected depending on the strength of the grains. Once the indent is done, a diamond-shaped indent appears and measurements are made to determine hardness.

Friability may be defined by the relative breakdown of a sample compared to a standard. Typically friability may be measured by ball milling grain for a given time, which is the same time used to ball mill a standard grain. After milling the residual grain/powder is screened and the amount of grain that has broken down is weighed. These measurements are compared to the starting amount of grain and then compared to the breakdown of the standard. This allows relative comparison of grain durability.

For example, ball mill friability may be measured by putting a given amount of grain in a ball mill container with media (e.g., tungsten carbide) and milling for a set time. Typically the time is dependent on when the standard or baseline grain reaches about <NUM>% breakdown. This means <NUM>% of the starting weight of the grain can pass through a small opening screen.

The standard for friability may be chosen based on the grain being tested. For example if a very friable grain (i.e., it breaks down more easily) is being considered, a standard would be chosen with like-friability. For BFA samples a more durable alumina standard may be chosen. The standard chosen also depends on the application to determine relevance of the standard.

Embodiments of the BFA also may have a friability of not greater than about <NUM>% of the standard. For example, the BFA may have a friability of not greater than about <NUM>%, such as not greater than about <NUM>%. Non-limiting embodiments of the BFA may have a friability of at least about <NUM>%, such as at least about <NUM>%, at least about <NUM>%, or even at least about <NUM>%. The BFA of the abrasive cutting tool can have a friability within a range between any of the minimum and maximum values noted above. The classic alundum grain can be <NUM>% more friable than the blue fired alumina.

The abrasive particles of the mixture and the final-formed abrasive article may include more than one type of abrasive particle. For example, the mixture can include a second type of abrasive particle different than the first type of abrasive particle. The second type of abrasive particle can differ from the first type of abrasive particle by any one of a composition, a mechanical property (e.g., hardness, friability, etc.), particle size, a method of making, or a combination thereof.

For example, the second type of abrasive particle may comprise alumina, zirconia or alumina and zirconia. The second type of abrasive particle may comprise essentially alumina and zirconia.

The second type of particle may comprise blue fired alumina (BLFA). For example, the second type of particle may comprise Treibacher blue fired alumina.

In some examples of the abrasive cutting tool, the BLFA may comprise not greater than about <NUM> vol% Al<NUM>O<NUM>. In other examples, the BLFA may comprise not greater than about <NUM> vol% Al<NUM>O<NUM>, such as not greater than about <NUM> vol% Al<NUM>O<NUM>. In other non-limiting examples, the BLFA may be at least about <NUM> vol% Al<NUM>O<NUM>, such as at least about <NUM> vol% Al<NUM>O<NUM>, or even at least about <NUM> vol% Al<NUM>O<NUM>. The BLFA of the abrasive cutting tool can have a Al<NUM>O<NUM> content within a range between any of the minimum and maximum values noted above.

In an alternate embodiment of the abrasive cutting tool, the BLFA may comprise not greater than about <NUM> vol% ZrO<NUM>. For example, the BLFA may be not greater than about <NUM> vol% ZrO<NUM>, such as not greater than about <NUM> vol% ZrO<NUM>, not greater than about <NUM> vol% ZrO<NUM>, or even not greater than about <NUM> vol% ZrO<NUM>. Other non-limiting embodiments of the BLFA may have at least about <NUM> vol% ZrO<NUM>, such as at least about <NUM> vol% ZrO<NUM>, or even at least about <NUM> vol% ZrO<NUM>. The BLFA of the abrasive cutting tool can have a ZrO<NUM> content within a range between any of the minimum and maximum values noted above.

BLFA may comprise oxides, such as BaO, CaO, Na<NUM>O, P<NUM>O<NUM>, and a combination thereof. For example, BLFA may include not greater than about <NUM> PPM BaO, such as not greater than about <NUM> PPM BaO, not greater than about <NUM> PPM BaO, or even not greater than about <NUM> PPM BaO.

Embodiments of BLFA also may include not greater than about <NUM> PPM CaO. For example, BLFA can be not greater than about <NUM> PPM CaO, such as not greater than about <NUM> PPM CaO.

Other embodiments of BLFA also may include not greater than about <NUM> PPM Na<NUM>O. For example, BLFA can be not greater than about <NUM> PPM Na<NUM>O, such as not greater than about <NUM> PPM Na<NUM>O.

Still other embodiments of BLFA may include greater than about <NUM> PPM P<NUM>O<NUM>. For example, BLFA can be greater than about <NUM> PPM P<NUM>O<NUM>, such as greater than about <NUM> PPM P<NUM>O<NUM>, or even greater than about <NUM> PPM P<NUM>O<NUM>.

In contrast to BLFA, embodiments of BFA may contain very different amounts of oxides described above for BLFA. For example, BFA may include at least about <NUM> PPM BaO, such as at least about <NUM> PPM BaO, or even at least about <NUM> PPM BaO.

Embodiments of BFA also may include greater than about <NUM> PPM CaO. For example, BFA can be greater than about <NUM> PPM CaO, such as greater than about <NUM> PPM CaO.

Other embodiments of BFA also may include greater than about <NUM> PPM Na<NUM>O. For example, BFA can be greater than about <NUM> PPM Na<NUM>O, such as greater than about <NUM> PPM Na<NUM>O.

Still other embodiments of BFA may include not greater than about <NUM> PPM P<NUM>O<NUM>. For example, BFA can be not greater than about <NUM> PPM P<NUM>O<NUM>, such as not greater than about <NUM> PPM P<NUM>O<NUM>, or even not greater than about <NUM> PPM P<NUM>O<NUM>.

In other embodiments, the second type of abrasive particle may comprise not greater than about <NUM> vol% Al<NUM>O<NUM>. For example, the second type of abrasive particle may not be greater than about <NUM> vol% Al<NUM>O<NUM>, such as not greater than about <NUM> vol% Al<NUM>O<NUM>. Non-limiting embodiments of the second type of abrasive particle may be at least about <NUM> vol% Al<NUM>O<NUM>, such as at least about <NUM> vol% Al<NUM>O<NUM>, or even at least about <NUM> vol% Al<NUM>O<NUM>. The second type of abrasive particle can have a Al<NUM>O<NUM> content within a range between any of the minimum and maximum values noted above.

In another embodiment, the second type of abrasive particle may comprise not greater than about <NUM> vol% ZrO<NUM>. Other examples of the second type of abrasive particle may be not greater than about <NUM> vol% ZrO<NUM>, such as not greater than about <NUM> vol% ZrO<NUM>, or even not greater than about <NUM> vol% ZrO<NUM>. Non-limiting examples of the second type of abrasive particle may be at least about <NUM> vol% ZrO<NUM>, such as at least about <NUM> vol% ZrO<NUM>, or even at least about <NUM> vol% ZrO<NUM>. The second type of abrasive particle can have a ZrO<NUM> content within a range between any of the minimum and maximum values noted above.

Other embodiments of the second type of abrasive particle may have a hardness not greater than about <NUM> GPa. For example, the second type of abrasive particle may have a hardness not greater than about <NUM> GPa, such as not greater than about <NUM> GPa, or even not greater than about <NUM> GPa. Non-limiting examples of the second type of abrasive particle may have a hardness of at least about <NUM> GPa, such as at least about <NUM> GPa, or even at least about <NUM> GPa. The second type of abrasive particle can have a hardness within a range between any of the minimum and maximum values noted above.

In another example, the second type of abrasive particle may have a friability of not greater than about <NUM>%. In a particular instance, the second type of abrasive particle may have a friability of not greater than about <NUM>%, such as not greater than about <NUM>%. Non-limiting embodiments of the second type of abrasive particle may have a hardness of at least about <NUM>%, such as at least about <NUM>%, at least about <NUM>%, or even at least about <NUM>%. The second type of abrasive particle can have a friability within a range between any of the minimum and maximum values noted above.

According to another embodiment, the abrasive particles can be shaped abrasive particles. Shaped abrasive particles can have a well-defined and regular arrangement (i.e., non-random) of edges and sides, thus defining an identifiable shape. For example, a shaped abrasive particle may have a polygonal shape as viewed in a plane defined by any two dimensions of length, width, and height. Some exemplary polygonal shapes can be triangular, quadrilateral (e.g., rectangular, square, trapezoidal, parallelogram), a pentagon, a hexagon, a heptagon, an octagon, a nonagon, a decagon, and the like. Additionally, the shaped abrasive particle can have a three-dimensional shape defined by a polyhedral shape, such as a prismatic shape or the like. Further, the shaped abrasive particles may have curved edges and/or surfaces, such that the shaped abrasive particles can have convex, concave, ellipsoidal shapes.

The shaped abrasive particles can be in the form of any alphanumeric character, e.g., <NUM>, <NUM>, <NUM>, etc., A, B, C. etc. Further, the shaped abrasive particles can be in the form of a character selected from the Greek alphabet, the modern Latin alphabet, the ancient Latin alphabet, the Russian alphabet, any other alphabet (e.g., Kanji characters), and any combination thereof.

The shaped abrasive particle can have a body defining a length (<NUM>), a height (h), and a width (w), wherein the length is greater than or equal to the height, and the height is greater than or equal to the width. Further, in a particular aspect, the body may include a primary aspect ratio defined by the ratio of length:height of at least about <NUM>:<NUM>. The body may also include an upright orientation probability of at least about <NUM>%.

In another aspect, the shaped abrasive particle can have a body having a length (<NUM>), a width (w), and a height (h), wherein the length, width, and height may correspond to a longitudinal axis, a lateral axis, and a vertical axis, respectively, and the longitudinal axis, lateral axis, and vertical axis may define three perpendicular planes. In this aspect, the body may include an asymmetric geometry with respect to any of the three perpendicular planes.

In yet another aspect, the shaped abrasive particle may include a body having a complex three-dimensional geometry including <NUM>-fold symmetry in three perpendicular planes defined by a longitudinal axis, a lateral axis, and a vertical axis. Further, the body may include an opening that extends through the entire interior of the body along one of the longitudinal axis, lateral axis, or vertical axis.

In still another aspect, the shaped abrasive particle may include a body having a complex three-dimensional geometry defined by a length (<NUM>), a width (w), and a height (h). The body may also include a center of mass and a geometric midpoint. The center of mass may be displaced from the geometric midpoint by a distance (Dh) of at least about <NUM>(h) along a vertical axis of the body defining the height.

In another aspect, the shaped abrasive particle may include a body that defines a length (<NUM>), a width (w), and a height (h). The body may include a base surface and an upper surface. Further, the base surface comprises a different cross-sectional shape than a cross-sectional shape of the upper surface.

In still another aspect, the shaped abrasive particle may include a body that has a generally flat bottom and a dome shaped top extending from the generally flat bottom.

In another aspect, the shaped abrasive particle may include a body comprising a length (<NUM>), a width (w), and a height (h). The length, width, and height may correspond to a longitudinal axis, a lateral axis, and a vertical axis, respectively. Further, the body may include a twist along a longitudinal axis defining the length of the body such that a base surface is rotated with respect to an upper surface to establish a twist angle.

In yet another aspect, the shaped abrasive particle may include a body having a first end face and a second end face a, at least three adjacent side faces extending between the first end face and the second end face, and an edge structure established between each pair of adjacent side faces.

In another aspect, the shaped abrasive particle may include a body having a central portion and at least three radial arms extending outwardly from the central portion along the entire length of the central portion.

The abrasive cutting tool may comprise embodiments wherein the bond material comprises resin. The resin can be at least about <NUM> vol% of a total volume of the bond material. In other examples, the resin may be at least about <NUM> vol% of the total volume of the bond material, such as at least about <NUM> vol%, or even at least about <NUM> vol%. In other non-limiting embodiments, the resin can be not greater than about <NUM> vol% of the total volume of the bond material, such as not greater than about <NUM> vol%, or even not greater than <NUM> vol%. The resin content can be within a range between any of the minimum and maximum values noted above.

In other embodiments of the abrasive cutting tool, the bond material comprises a resin having a high temperature flexure modulus of at least <NUM>. In other embodiments the bond material may comprise a resin having an increasing high temperature flexural modulus.

In some embodiments, the resin used in the bond material may comprise an organic resin. In other embodiments, the resin may comprise a phenolic resin. In still other embodiments, the phenolic resin may be modified with a curing or cross-linking agent, such as hexamethylene tetramine. At temperatures in excess of about <NUM>, some examples of the hexamethylene tetramine may form crosslinks to form methylene and dimethylene amino bridges that help cure the resin. The hexamethylene tetramine may be uniformly dispersed within the resin. More particularly, hexamethylene tetramine may be uniformly dispersed within resin regions as a cross-linking agent. Even more particularly, the phenolic resin may contain resin regions with cross-linked domains having a sub-micron average size.

Embodiments of the abrasive cutting tool also may comprise the body having a K2SO4 (or CVR) index of at least about <NUM> % greater than a body of a conventional abrasive cutting tool. The CVR Index may comprise the formula:
<MAT>
wherein CVR1 is a CVR surface coverage of the body, and CVR2 is a CVR surface coverage of the body of the conventional abrasive cutting tool.

The values CVR1 and CVR2 may be determined by a CVR determination method. For example, a sample abrasive article (e.g., a sample of an abrasive cutting wheel) may be exposed to 75kW for <NUM> minutes under a cone calorimeter experiment per ISO <NUM>. The sample is then surface mapped with an SEM/EDX instrument for the formation of CVR or K2SO4 on the surface of the sample.

In some examples, the CVR index of the body can be at least about <NUM>% greater than the body of the conventional abrasive cutting tool. Alternatively, the CVR index can be at least about <NUM>% greater than the body of the conventional abrasive cutting tool, such as at least about <NUM>% greater, at least about <NUM>% greater, at least about <NUM>% greater, at least about <NUM>% greater at least about <NUM>% greater, at least about <NUM>% greater, or even at least about <NUM>% greater than the body of the conventional abrasive cutting tool. The CVR index can be within a range between any of the minimum and maximum values noted above.

In other examples of the abrasive cutting tool, the CVR index of the body is not greater than about <NUM>% greater than the body of the conventional abrasive cutting tool. For example, the CVR index of the body can be not greater than about <NUM>% greater than the body of the conventional abrasive cutting tool, such as no greater than about <NUM>% greater, not greater than about <NUM>% greater, not greater than about <NUM>% greater, not greater than about <NUM>% greater, not greater than about <NUM>% greater, not greater than about <NUM>% greater, or even not greater than about <NUM>% greater than the body of the conventional abrasive cutting tool. The CVR index can be within a range between any of the minimum and maximum values noted above.

In some embodiments, the body may have a Thermal Adhesion Factor (TAF) of at least about <NUM>%. In other embodiments, the TAF of the body is at least about <NUM>%, at least about <NUM>%, at least about <NUM>%, at least about <NUM>%, not greater than <NUM>%, not greater than <NUM>%, or even not greater than <NUM>%. The TAF can be within a range between any of the minimum and maximum values noted above.

In addition, the body of the abrasive cutting tool may comprise a baseline Adhesion Value (AVb) of at least about <NUM>,45kN (550lbf), at least about <NUM>,56kN (575lbf), at least about <NUM>,67kN (600lbf), at least about <NUM>,78kN (625lbf), at least about <NUM>,89kN (650lbf), and not greater than about <NUM>,56kN (800lbf), not greater than about <NUM>,34kN (750lbf), or even not greater than about <NUM>,11kN (700lbf). The AVb can be within a range between any of the minimum and maximum values noted above.

Moreover, the body of the abrasive cutting tool may comprise a thermal treatment Adhesion Value (AVtt) of at least about <NUM>,67kN (150lbf), at least about <NUM>,78kN (175lbf), at least about <NUM>,89kN (200lbf), at least about <NUM>,00kN (225lbf), at least about <NUM>,11kN (250lbf), at least about <NUM>,22kN (275lbf), and not greater than about <NUM>,78kN (400lbf), not greater than about <NUM>,56kN (350lbf), or even not greater than about <NUM>,33kN (300lbf). The AVtt can be within a range between any of the minimum and maximum values noted above.

Samples S1 and S2 were prepared and are identical with regard to grain blend, grade and structure, bond system according to an embodiment herein, and wheel construction. Sample S1 and S2 comprised <NUM>% abrasive, <NUM>% bond, and <NUM>% pores. The grain blend was <NUM>% ZF grain and <NUM>% brown fused alundum.

Samples S1 and S2 are distinct from each other based upon their reinforcing members. Sample S1 included IPAC-standard <NUM> reinforcing members, while sample S2 included SGTF-<NUM> reinforcing members, commercially available from Adfors. Construction details regarding the reinforcing member for sample S1 include a thickness of about <NUM> inches (<NUM>). The reinforcing member comprised about <NUM> vol% of a total volume of the body. The reinforcing member may comprise about <NUM> vol% to <NUM> vol% of the total volume of the body. The reinforcing member comprises fiber bundles with openings therebetween, and the openings comprise an area of <NUM><NUM> (i.e., 3x3 mm). The reinforcing member comprises fiber bundles have a warp filament diameter of <NUM> microns.

Differential Scanning Calorimetry (DSC) measures the temperatures and heat flows associated with transitions in materials as a function of time and temperature in a controlled atmosphere. These measurements provide quantitative and qualitative information about physical and chemical changes that involve endothermic or exothermic processes, or changes in heat capacity. DSC was measured using approximately a <NUM> sample of fiberglass in a nitrogen environment. The sample was ramped to <NUM> at a ramp of <NUM>/min and held for <NUM> minutes. For sample S1, the reinforcing member had a DSC enthalpy of reaction of about <NUM> J/g, and a DSC enthalpy of crystallization of <NUM> J/g.

Construction details regarding the reinforcing member for sample S2 include a thickness of about <NUM> (range: about <NUM> to about <NUM>). The reinforcing member comprises <NUM> vol% of a total volume of the body (range is about <NUM> vol% to about <NUM> vol%). The reinforcing member comprises fiber bundles with openings therebetween, and the openings comprise an area of <NUM><NUM> (i.e., 4x4 mm). The reinforcing member comprises fiber bundles have a warp filament diameter of <NUM> or <NUM> microns. The same DSC tests described above were performed on sample S2. The S2 reinforcing member had a DSC enthalpy of reaction of about <NUM> J/g, and a DSC enthalpy of crystallization of <NUM> J/g.

<FIG> include computed tomography (CT) images of abrasive tools illustrating porosity with samples S1 and S2, respectively. The microstructure of sample S2 is significantly better than that of sample S1. Although the fiberglass layers are difficult to differentiate, the porosity distribution is clearly shown. Sample S1 has significantly more porosity around the glass webs.

<FIG> include plots of porosity in abrasive tool samples S1 and S2, respectively. These plots compare area fraction porosity (y-axis) as a function of axial location or thickness (x-axis) in the samples. There is clearly a higher percentage of porosity around the glass web in sample S1 than sample S2. After integration of the porosity, it was observed that samples S1 had between <NUM> vol% and <NUM> vol% porosity, whereas the porosity of samples S2 was reduced to <NUM> vol% to <NUM> vol%.

Thus, the body may comprise not greater than about <NUM> vol% porosity for the total volume of the body, not greater than about <NUM> vol%, not greater than about <NUM> vol%, not greater than about <NUM> vol%, not greater than about <NUM> vol%, at least about <NUM> vol%, at least about <NUM> vol%, at least about <NUM> vol%.

At the interface between the reinforcing member and the abrasive portion the body has a Maximum Porosity Index (MPI) that may be calculated by subtracting the peak value from the minimum valley value, and then dividing the difference by the minimum valley value. These calculations are based on a graph obtained by conducting a scan of the material under particular conditions. The MPI is based on the largest difference from the curve of a minimum corresponding to a position of the reinforcing member positioned between two maximums, indicating interfacial porosity at the interface of the abrasive portion and the reinforcing member.

For example, in <FIG> the peak value is <NUM>% and is found adjacent the middle reinforcing member. The minimum valley value in <FIG> is <NUM>%. Thus, the maximum porosity index (MPI) for <FIG> is (<NUM>-<NUM>)/<NUM>] x <NUM>% = <NUM>%. In contrast, the maximum porosity index (MPI) of <FIG> is found adjacent the left reinforcing member and is (<NUM>-<NUM>)/<NUM>] x <NUM>% = <NUM>%.

Thus, at an interface between the reinforcing member and the abrasive portion, the body may have a Maximum Porosity Index of less than about <NUM>%, less than about <NUM>%, less than about <NUM>%, less than about <NUM>%, less than about <NUM>%.

In addition, the dashed horizontal lines extending across <FIG> portray the average area fraction porosity of each is about <NUM>% and <NUM>%, respectively, at an interface with the reinforcing member. Thus, the body may have an average area fraction porosity of not greater than about <NUM>% at an interface with the reinforcing member, not greater than about <NUM>%, not greater than about <NUM>%, not greater than about <NUM>%; at least about <NUM>%, at least about <NUM>%, at least about <NUM>%.

<FIG> include images of an adhesion measure test (i.e., Thermal Adhesion Factor (TAF)) performed on samples S1 and S2. Each sample was notched as shown in <FIG>. The samples were then placed in a fixture as shown in <FIG>. Force is applied to the notched samples and the force needed to split the sample (<FIG>) is used to compare adhesion at the glass web interface.

The adhesion of each sample was tested before and after a heat soak. The samples were heated to <NUM> and held for <NUM> hours and then measured for adhesion. Adhesion as a function of heat soak time appears in Table <NUM>.

The data shown in Table <NUM> shows the adhesion change as a function of soak time at <NUM> relative to baseline measurements taken at room temperature. To determine thermal resistance samples were placed in a <NUM> oven and allowed to soak for <NUM> minutes. After soaking, the samples were removed from the oven and allowed to cool. Adhesion was then measured on all samples and compared to the baseline. Samples S1 retained only <NUM>% of the baseline adhesion, while samples S2 retained <NUM>% of the baseline adhesion. Data was taken on a sample size of ten measurements at each condition. Sample S2 shows an improvement in TAF or thermo degradation resistance compared to sample S1.

<FIG> includes a plot of a bake profile for embodiment S2 of the abrasive wheel, described above. Conventional samples did not present any bake problems when its reinforcing members were changed from a standard IPAC glass to the glass of sample S2. The same bake cycle performed well for all types of fiberglass webs tested in conventional samples. However, substitution of the new glass into sample S2 and its higher temperature bake cycle generated significant geometry issues for the samples.

As shown in <FIG>, the bake cycle for sample S2 with the conventional fiberglass webs originally lasted <NUM> hours at a maximum soak temperature of <NUM>. Sample S2 with standard fiberglass webs had a rejection rate of approximately <NUM>% based on geometry, the new fiber glass composite caused a strong shift in geometry leading to a <NUM>% rejection rate. See <FIG> for photographs comparing unacceptable and acceptable product, respectively.

To remediate this problem, the bake cycle for samples containing the new web was decreased by <NUM> hours. In addition, the clamping weight used was increased by a factor of <NUM> (i.e., <NUM> instead of <NUM>). This corresponds to approximately <NUM>/cm<NUM> for <NUM> diameter wheels. With these changes the geometry of ensuing samples S2 with the new web was <NUM>% within tolerance. In conclusion, there were clear differences in behavior between standard (IPAC) fiberglass and the new fiberglass observed in conjunction with a higher temperature bake. Thus, processing changes were necessary due to the compositional and structural differences of the various embodiments.

The new fiberglass appears to be more sensitive to temperature than standard fiberglass, leading to a progressive shrinkage during the bake. By reducing the bake time, this impact was reduced while maintaining acceptable curing conditions and thermo mechanical characteristics.

This written description uses examples to disclose the embodiments, including the best mode, and also to enable those of ordinary skill in the art to make and use the invention. The patentable scope is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

In the foregoing specification, the concepts have been described with reference to specific embodiments. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of invention.

For example, a process, method, article, or apparatus that comprises a list of features is not necessarily limited only to those features but may include other features not expressly listed or inherent to such process, method, article, or apparatus.

Also, the use of "a" or "an" are employed to describe elements and components described herein. This description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.

Claim 1:
An abrasive cutting tool (<NUM>, <NUM>) comprising:
a body (<NUM>, <NUM>) in a shape of a large diameter disk having an outer diameter (<NUM>) of at least <NUM> centimeters, and an aspect ratio defined as a ratio (D:T) between the outer diameter to an axial thickness of the body of at least <NUM>:<NUM>,
and the body including an abrasive portion having:
a bond material;
abrasive particles contained within the bond material;
a first filler contained within the abrasive portion comprising iron and sulfur having an average particle size of not greater than <NUM> microns;
wherein the body further comprises one or more reinforcing members (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>);
characterized in that the one or more reinforcing members comprises <NUM> to <NUM> vol% of a total volume of the body, and
a plurality of openings, wherein the opening each defines an open area of at least <NUM><NUM> and not greater than <NUM><NUM> within a major plane of the reinforcing member.