Patent Description:
Metal balls, such as steel balls found in ball bearings for example, are typically cold-formed or in some instances hot formed. Metal balls resulting from these processes sometimes have regions which are referred as "poles". Regions of the metal balls corresponding or located near the poles can have different properties than regions that are, for example, closer to the equator, i.e., regions located elsewhere than at or near the poles. Localized or general material properties affected by in service usage and fatigue damage may be of interest (e.g., localized spalling, fatigue damage, heat damage) or thermo-mechanical effects as a result of LCF (low cycle fatigue), HCF (high cycle fatigue), monotonic loading, and others may be of interest as they may or may not affect the quality of the ball. Such analyses may be employed on coatings and substrates as applicable.

Some of the properties which might be of interest in the case of steel balls include but are not limited to residual stress (RS), strain or crystallographic strain, and percent retained austenite (%RA). When it comes to Fe-base alloys and other materials or metals, such as titanium for example, other properties can be of interest. Indeed, one may be interested into phase mapping the material (e.g., for mapping the alpha and/or beta phases) or characterize the dislocation density and particle size within the material via various methods (e.g., via methods including but not limited to Warren-Averbach, including variations, Williamson-Hall, Voigt, Scherer, empirical methods with or without reference standard, and the like) and/or direct measures of FWHM (full width half maximum), integral breadth of other forms of peak shape/profile analyses may provide useful information. Texture analysis, pole figures and ODF (orientation distribution function), crystal orientation, and others may also be properties of interest for characterization as well as strain pole figures. Other properties such as the lattice parameter (or unstressed lattice spacing) and others may be used to calculate %Carbon and other similar or dissimilar properties i.e., composition related physical, mechanical, electrical, optical, or other performance related properties. Coating thickness and quality may also be determined by a variety of methods and techniques. Characterizing the abovementioned properties may or may not require complex mechanical systems or destructive methods.

Many challenges still exist in the field of ball-mapping systems for locating the poles in a non-destructive manner using an X-ray diffraction apparatus. <CIT> discloses a ball-mapping system. <NPL> discloses a method for mapping of a ball-shaped sample using X-ray diffraction.

In accordance with one aspect, there is provided a method for mapping of a ball-shaped sample using X-ray diffraction. The method includes placing the ball-shaped sample on a sample-contacting surface; restricting movement of the ball-shaped sample with respect to the sample-contacting surface; translating the sample-contacting surface along a first axis and a second axis unparallel to the first axis, thereby causing the ball-shaped sample to rotate on the sample-contacting surface along of the first axis and the second axis to align a plurality of measurement points with an X-ray beam originating from an X-ray diffraction apparatus; and operating the X-ray diffraction apparatus to collect X-ray diffraction data at each one of the measurement points.

In some embodiments, translating the sample-contacting surface includes independently translating the sample-contacting surface along the first axis and the second axis unparallel to the first axis to sequentially align said plurality of measurement points with the X-ray beam originating from the X-ray diffraction apparatus.

In some embodiments, translating the sample-contacting surfaces includes simultaneously translating the sample-contacting surface along the first axis and the second axis unparallel to the first axis to align said plurality of measurement points with the X-ray beam originating from the X-ray diffraction apparatus.

In some embodiments, translating the sample-contacting surface includes operating a motor assembly in driving engagement with a guide assembly cooperating with the sample-contacting surface for driving the sample-contacting surface in translational movement along the first axis and the second axis.

In some embodiments, the first axis and second axis are orthogonal.

In some embodiment, the method further includes rotating the sample holder by a predetermined angle to adjust a rotational degree-of-freedom of the sample holder.

In some embodiments, translating the sample-contacting surface includes preventing the ball-shaped sample from sliding when the sample-contacting surface is in movement with respect to the ball-shaped sample.

In some embodiments, operating the X-ray diffraction apparatus includes collecting between about <NUM> to about <NUM> measurement points. In some embodiments, operating the X-ray diffraction apparatus includes collecting more than <NUM> measurement points.

In some embodiments, the method includes generating a model representative of a surface of the ball-shaped sample and distributing virtual measurement points on the model, the virtual measurement points being representative of the measurement points. In some embodiments, the model is a polygon having a center coinciding with a center of the ball-shaped sample. In some embodiments, the model is an icosahedron.

In the following description, similar features in the drawings have been given similar reference numerals. In order to not unduly encumber the figures, some elements may not be indicated on some figures if they were already mentioned in preceding figures. It should also be understood herein that the elements of the drawings are not necessarily drawn to scale and that the emphasis is instead being placed upon clearly illustrating the elements and structures.

It will be appreciated that positional descriptions such as "top", "bottom", "above", "under", "below", "left", "right", "front", "rear", "parallel", "perpendicular", "transverse", "inner", "outer", "internal", "external", and the like should, unless otherwise indicated, be taken in the context of the figures and should not be considered limiting.

The terms "X-ray", "X-radiation", "light", "electromagnetic radiation", "optical", "spectral profile" "spectral waveband", derivatives and variants thereof, are used to refer to radiation in any appropriate region of the electromagnetic spectrum and, more particularly, are not limited to visible light. By way of example, the X-rays may cover or substantially correspond to wavelengths ranging from <NUM> to <NUM> nanometers (i.e., frequencies in the range of <NUM> petahertz to <NUM> exahertz), which may be of particular interest for applications in the materials science industry for investigating the structural and/or mechanical properties of samples. Such properties include but are not limited to atomic structure, phase mapping, dislocation, residual stress and percent retained austenite (sometimes referred to as "%RA").

The terms "sample", "sample under investigation", "material", "analyzed sample", "powder", "thin films", derivatives and variants thereof are used to refer to a quantity of matter extracted or taken apart from a larger amount for analysis, or may refer to matter that is either natural (e.g., a specific chemical element found in nature), synthesized (e.g., a reaction of chemical compounds), or man-made (e.g., a power formed by scratching a thin film). It will be understood that the sample intrinsically has various physical and chemical properties, which may be assessed using different instruments and methods (e.g., XRD analysis). In the context of the current disclosure, it is to be noted that the samples to be characterized are typically substantially spherical, and so will sometimes be referred to as "spherical samples", "ball-shaped samples" or simply "balls". More generally, the samples can have a round, roundish, globular or ovoid body. In some scenarios, the samples can be a portion of sphere (e.g., a hemisphere).

The terms "diffractometer", "X-ray diffraction apparatus", "XRD diffraction system", "powder diffraction instruments", "X-ray apparatus", derivatives and variants thereof refer to an apparatus configured to acquire patterns obtained by recording the intensities of X-rays scattered by the sample under investigation at different angles between an incident beam (i.e., beam incident on the sample) and a scattered beam (also referred to as "reflected beam"). The acquired patterns are typically representative of given properties (e.g., structure) of the material to be inspected. The above-mentioned apparatus could further be understood as a device configured to sense and/or probe x-rays scattered and/or reflected by the surface to be inspected, according to the needs of a particular application.

The XRD apparatus may include an X-ray source (including, for example, a vacuum-sealed X-ray tube or incorporate into a high flux source such as a synchrotron, liquid metal jet, or any other, or any neutron source), an X-ray generator delivering high tension current to the X-ray source, a sample holder to hold the sample to be investigated, an X-ray detector capable of detecting X-ray and/or X-ray photons scattered by the sample and an X-ray optical assembly (typically used for collimating, conditioning, or focusing the X-rays at the detector). The XRD pattern is obtained by recording the intensities of X-rays scattered by the sample at different angles between the beam incident on the sample and beam scattered by the sample.

In the following description, the "XY plane" is defined as a plane substantially parallel to (or a plane coinciding with) a surface, a portion or a section of the sample to be characterized. In such scenario, a "Z direction" or, alternatively, a "Z axis", and variants thereof (e.g., "Z plane") will hence be understood as the axis being substantially perpendicular to the XY plane (i.e., the surface of the sample). Broadly, the present description will refer to the "X, Y, Z planes" as being three perpendicularly intersecting planes. For the sake of clarity and concision of the present description, the XY plane will herein be referred to as lying in a horizontal plane (i.e., a horizontal direction), while the Z axis will be referred to as lying in a vertical plane (i.e., a vertical direction).

It will be readily understood that the ball mapping as it will be described below can also be performed on a variety of materials, including but not limited to steel, titanium and carbides. It is to be noted that specific properties of each materials can be mapped.

Referring to <FIG> and <FIG>, a ball-mapping system <NUM> is shown. The ball-mapping system <NUM> includes a sample holder <NUM>, which will now be described in greater detail.

The sample holder <NUM> is configured to hold a sample (not shown in <FIG> and <FIG>, but illustrated, for example as a ball-shaped sample, in <FIG> and <FIG>) in place during measurements. The sample holder <NUM> includes a sample-receiving cavity <NUM> for receiving the sample therein. The sample-receiving cavity <NUM> is depicted as having a substantially circular cross-section and as such defines a substantially cylindrical sample-receiving cavity <NUM>, i.e., the sample-receiving cavity <NUM> has a substantially cylindrical body. As illustrated, the substantially cylindrical body extends between a top end portion and a bottom end portion. This configuration of the sample-receiving cavity <NUM> allows the sample holder <NUM> to receive and hold a substantially spherical (i.e., a ball-shaped) sample in place. Of course, the shape of the sample-receiving cavity <NUM> can differ from the substantially circular cross-section illustrated in the Figures, as long as the sample-receiving cavity <NUM> is shaped and configured to receive the ball-shaped sample therein and allows its relative movement with other components of the ball-mapping system <NUM> that will be later described.

In some sample holders wherein the sample-receiving cavity <NUM> has a substantially cylindrical body, a diameter (i.e., a dimension taken along a cross-section of the sample-receiving cavity <NUM>), of the sample-receiving cavity <NUM> can be substantially equal to a diameter of the sample to be characterized, or slightly smaller such that the sample tightly fits in the sample-receiving cavity <NUM>. Alternatively, the diameter of the sample-receiving cavity <NUM> can either be greater or smaller than the diameter of the sample. It has to be noted that the geometrical configuration, including the shape and dimensions of the sample-receiving cavity <NUM>, are designed and configured in a way that the sample can be held in the sample-receiving cavity <NUM>. As such, in the alternatives in which the diameter of the sample-receiving cavity <NUM> is greater than the diameter of the sample, a mechanism or appropriate component(s) can be provided to hold the sample in place in the sample-receiving cavity <NUM>.

In the other illustrated sample holders, the sample-receiving cavity <NUM> is provided with an iris diaphragm <NUM>. In some sample holders, the iris diaphragm <NUM> is located at the bottom end portion of the sample-receiving cavity <NUM> or, in other sample holders, close to the bottom end portion of the sample-receiving cavity <NUM>. Alternatively, the iris diaphragm <NUM> could be provided in the middle portion of the sample-receiving cavity <NUM>, i.e., between the top end and bottom end portions defining the extremities of the sample-receiving cavity <NUM>, or in the top portion of the sample-receiving cavity <NUM>. In other sample holders, the iris diaphragm <NUM> can be provided anywhere between the top portion and the middle portion or anywhere between the middle portion and the bottom portion. In some sample holders, the iris diaphragm <NUM> can be omitted, and the sample-receiving cavity <NUM> can be, for example and without being limitative, continuously tapered from the top end portion towards the bottom end portion. In this example, the bottom end portion and the top end portion each has a respective inner diameter, and the inner diameter of the bottom end portion is smaller than the inner diameter of the top end portion. Such a continuously tapered sample-receiving cavity <NUM> can accommodate ball-shaped samples having various dimensions.

The iris diaphragm <NUM> is adjustable to contract or expand within the sample-receiving cavity <NUM>, thereby allowing to control a diameter of its central aperture <NUM>, which in turn results in adjusting a diameter of a section of the sample-receiving cavity <NUM>. The expression "contract" herein refers to a configuration in which the diameter of the section of the sample-receiving cavity <NUM> is reduced, whereas the expression "expand" herein refers to a configuration in which the diameter of the section of the sample-receiving cavity <NUM> is increased. The control of the diameter of the central aperture of the iris diaphragm <NUM> allows providing support for or applying pressure to ball-shaped samples having various dimensions.

In the sample holder shown, the iris diaphragm <NUM>, and more particularly the diameter of its central aperture <NUM>, can be adjusted by a lever <NUM> associated to a ring <NUM>. The ring <NUM> extends along an outer periphery of the iris diaphragm <NUM> (i.e., the ring <NUM> surrounds the iris diaphragm <NUM>), such that, upon a rotation of the lever <NUM>, either by a user or mechanical action (e.g., a motor), the iris diaphragm <NUM> contracts or expands, thereby changing the diameter of its central aperture <NUM>. Of course, one would readily understand that the lever <NUM> could be any other component(s) or mechanism cooperating with the iris diaphragm <NUM> to adjust the central aperture <NUM>, and so that the lever <NUM> only serves the purpose of a further sample holder.

When the sample is mounted into the sample holder <NUM>, the iris diaphragm <NUM> is configured to support the sample within the sample-receiving cavity <NUM> and to allow a portion of the sample to protrude below the sample holder <NUM>. As a result, a portion of the sample can extend below the iris diaphragm <NUM> (and so below the sample holder <NUM>). In the illustrated sample holder a bottom portion of the ball-shaped sample projects downwardly from the iris diaphragm <NUM>, with respect to the z-axis, when the ball-shaped sample is mounted in the sample-receiving cavity <NUM>.

Depending of the relative height of the iris diaphragm <NUM> within the sample-receiving cavity <NUM> (i.e. the positioning of the iris diaphragm <NUM> within the sample-receiving cavity <NUM>), the sample can be mounted at different height (i.e., a direction parallel to the z-axis) therein. In some sample holders the iris diaphragm <NUM> is close enough to the bottom portion of the sample-receiving cavity <NUM> to allow a spherical segment (i.e., a spherical cap or dome) to hang from the iris diaphragm <NUM> below the lower portion of the sample-receiving cavity <NUM>. In some sample holders, the iris diaphragm <NUM> is provided in the top portion of the sample-receiving cavity <NUM> and is configured to provide support or apply pressure to the sample.

Adjustment of the sample at a proper height within the sample-receiving cavity <NUM> can be carried by different means and methods which are globally referred to "calibration" or "adjustment" of the sample within the sample holder <NUM>. Such calibration or adjustment includes but are not limited to varying the diameter of the central aperture <NUM> of the iris diaphragm <NUM>.

Once the calibration or adjustment is made, the iris diaphragm <NUM> can contact the sample at different places. In some sample holders, the iris diaphragm <NUM> contacts the sample near its equator, i.e., a latitude located halfway between two opposite extremities of the sample. In other sample holders, the iris diaphragm <NUM> could contact the sample either under or above its equator. In some sample holders, the iris diaphragm <NUM> can be in direct contact with an entirety of the periphery of the sample. As it has been previously mentioned, the iris diaphragm <NUM> is generally configured for providing support or applying support to the sample. In other sample holders, the iris diaphragm <NUM> can be in direct contact with only portion(s) of the periphery of the sample, such as, for example and without being limitative, spaced-apart points distributed along the periphery of the sample. In such sample holders, the spaced-apart point could either being separated by a constant distance or a non-constant distance.

It is to be noted that the latitude at which the sample intersects or is supported by the iris diaphragm <NUM> can be a function of the size of the central aperture <NUM> and/or the sample and its specific geometrical configuration.

In some sample holders, the iris diaphragm <NUM> is made of a thin metal plate, and more particularly a plurality of interlocking metal blades. Alternatively, the iris diaphragm <NUM> could be made of plastic, polymer, or any other materials suitable for supporting the sample within the sample-receiving cavity <NUM>.

While the ball-shaped sample is illustrated as being held in place by the iris diaphragm <NUM>, the sample could also be held, in alternate sample holders, by different mechanism, means or components. For example, and without being limitative, the sample can be held in place with adjustable pins or conical-shaped piece for receiving the sample therein.

Still referring to <FIG> and <FIG>, the ball-mapping system <NUM> also includes a support frame <NUM> for supporting the sample holder <NUM>.

In the illustrated sample holder, the support frame <NUM> includes a horizontal beam <NUM> fixed, at its extremities, to a first vertical beam <NUM> and a second vertical beam <NUM>. Once assembled, the horizontal beam <NUM>, the first vertical beam <NUM> and the second vertical beam <NUM> defined an inverted U-shaped structure. Of course, the shape of the support frame <NUM> could vary depending on various factors, including, for example and without being limitative, the type of samples under investigation, as well as their geometrical configuration.

The horizontal beam <NUM>, as well as the first and second vertical beams <NUM>, <NUM> can be made of the same material. For example, and without being limitative, the beams <NUM>, <NUM>, <NUM> may be made from any solid material such as polymers (such as and without being limitative vinyl, fiberglass, rigid polyvinyl chloride (PVC)), metals including metal alloys (such as and without being limitative aluminum and aluminium alloys), stainless steel, brass, copper, combinations thereof, or any other material that can be configured to form the horizontal beam <NUM> or the vertical beams <NUM>, <NUM>. Of course, the beams <NUM>, <NUM>, <NUM> could have various geometrical configurations (i.e., size and dimensions). As depicted, they each have a substantially rectangular shape and comprise rectangular holes. Of course, they could, for example, have a triangular, rectangular, circular, or any other shaped holes.

In some sample holders, the first and second vertical beams <NUM>, <NUM> are fixed to the horizontal beam <NUM> through attachments joining the first and second vertical beams <NUM>, <NUM> to the horizontal beam <NUM> at each one of its extremities. In alternate sample holders, the support frame <NUM> could be made from an integral piece defined a structure of similar shape than the one described above.

In some sample holders, the ball-mapping system <NUM> also includes a base <NUM>. In the illustrated sample holders, the base <NUM> has a substantially circular outer periphery <NUM>, i.e., the base <NUM> has a circular or a disk-shaped body. In alternate sample holders, the general shape of the base <NUM> could vary. When the ball-mapping system <NUM> is not provided with the base <NUM>, the support frame <NUM>, and more particularly the first and second vertical beams <NUM>, <NUM>, can be fixed to the table onto which is mounted the ball-mapping system <NUM>. With reference to <FIG>, the base <NUM> can be mechanically connected to a supporting element <NUM>. In some sample holders, the supporting element <NUM> is mounted or connected to the XRD apparatus. The cooperation between the base <NUM> and the supporting element <NUM> can be such that the base <NUM> can be driven in a relative rotational movement with respect to the supporting element <NUM>. Such a relative rotational movement can be useful to adjust the position of the base <NUM>, and so the sample with respect to the XRD apparatus, e.g., the X-rays source and/or the detector (not illustrated in <FIG>).

The base <NUM> can be made from a broad variety of material, including but not limited to polymers (such as and without being limitative vinyl, fiberglass, rigid polyvinyl chloride (PVC)), metals including metal alloys (such as and without being limitative aluminum and aluminium alloys), stainless steel, brass, copper, combinations thereof, or any other material that can be configured to form the base <NUM>. The material(s) forming the base <NUM> could either be the same or different than the material(s) forming the support frame <NUM> or portion(s) thereof.

The support frame <NUM> can be engaged or fixed to the base <NUM>. In some sample holders, each one of the first and second lateral beams <NUM>, <NUM> are diametricallyopposed mounted to the base <NUM> at a respective one of their ends. It will be readily understood that the support frame <NUM> can either be directly or indirectly fixed to the base <NUM>. For example, in some sample holders, an attachment can be provided to ensure a better engagement between the support frame <NUM> and the base <NUM>, the attachment mechanically connecting each one of the first and second lateral beams <NUM>, <NUM> the base <NUM>.

As illustrated in <FIG>, the ball-mapping system <NUM> includes a sample stage <NUM>, which will now be described.

The sample stage <NUM> is positioned below the sample holder <NUM> and includes, in the illustrated embodiments, a guide assembly comprising a pair of guides, referred to as a first guide <NUM> and a second guide <NUM>.

The first guide <NUM> extends along an x-axis, i.e., the first guide <NUM> has a body extending along a longitudinal direction, which is parallel or coincides with the x-axis, perpendicular to the z-axis.

Similarly, the second guide <NUM> extends along a y-axis. The y-axis is unparallel to the x-axis and generally perpendicular to the z-axis. In some embodiments, the y-axis can be perpendicular to the x-axis.

The first and second guides <NUM>, <NUM> can have different geometrical dimensions and configuration, but are depicted, in the illustrated sample holders, as having a substantial rectangular cross-section.

It will be readily understood that the first and second guides <NUM>, <NUM> could be made from almost any material. For example, and without being limitative, the first and second guides <NUM>, <NUM> can be made of polymers (such as and without being limitative vinyl, fiberglass, rigid polyvinyl chloride (PVC)), metals including metal alloys (such as and without being limitative aluminum and aluminium alloys), stainless steel, brass, copper, combinations thereof, or any other material that can be configured to form a rectangular guide.

The sample stage <NUM> also includes a sample-contacting surface <NUM>. The sample-contacting surface <NUM> is engageable with the second guide <NUM> and is configured to contact the sample when the sample is mounted and hanging from the sample holder <NUM>, as it has been described above. It has to be noted that the sample-receiving cavity <NUM>, the iris diaphragm <NUM> and/or the combination thereof, which have all been described above, allow the sample to be suspended from the sample-receiving cavity <NUM>, such that the sample or at least a portion thereof is in direct contact with the sample-contacting surface <NUM>. The sample stage <NUM> can also include a magnetic sliding mechanism including one or more magnets, mounted under the sample-contacting surface <NUM>. In some sample holders, the magnetic sliding mechanism could be movable or guided in translation under the sample-contacting surface <NUM>, for example for assisting the rotational movement of the ball-shaped sample when the sample-contacting surface is in translational movement. In some implementations, the magnetic sliding mechanism can be part of the guide assembly.

The sample-contacting surface <NUM> is configured to be selectively adjustable along the x-axis and the y-axis. The expression "selectively" herein refers to the fact that the configuration of the first and second guides <NUM>, <NUM>, as well as the sample-contacting surface <NUM>, as it will be described herein below, allows to translate the sample-contacting surface <NUM> in one direction at a time. For example, the sample-contacting surface <NUM> could be sequentially translated in a direction parallel to the x-axis, and then in a direction parallel to the y-axis, or vice-versa. In some sample holders, the sample-contacting surface <NUM> is configured to be simultaneously adjustable along the x-axis and the y-axis. In these sample holders, the displacement along each axis is individually monitored or recorded.

In some sample holders, the sample-contacting surface <NUM> is made from a rubber mat. The sample-contacting surface <NUM> could be made from any type of material having a coefficient of static friction allowing the ball-shaped sample to roll thereon, while preventing the ball-shaped sample to slide on the sample-contacting surface <NUM>. Therefore, the coefficient of static friction of the sample-contacting surface <NUM> is substantially high in comparison to the coefficient of static friction of the sample.

Generally, the sample holder <NUM> is configured to prevent the ball-shaped sample from sliding on the sample-contacting surface <NUM> of the sample stage <NUM>, i.e., during its displacement, the sample rolls without sliding onto the sample-contacting surface <NUM> during its translation. As such, the sample can be characterized at each measurement point once, and it is possible to keep track of the position of each measurement point of the sample with respect to the XRD apparatus during the displacement of the sample. However, in some sample holders, the sample could slide on the sample-contacting surface <NUM> while rolling thereon. In such sample holders, a tracking unit can be used to track the position of the sample. For example, and without being limitative, the tracking unit can include a marking system, such as physical markings (e.g., dots, lines, shape, indentation or a combination thereof) provided on the sample's surface. The tracking unit can also include a detector for detecting the marking system. A non-limitative example of such a detector is a camera. or similar device, that could be configured to track the position of the marking system during the displacement (i.e., translation, sliding and/or rotation) of the sample.

The second guide <NUM> is engageable to the first guide <NUM> and, as illustrated in the sample holder of <FIG>, the second guide <NUM> is slidably engaged with the first guide <NUM>. The cooperation, e.g., the mechanical connection, between the first guide <NUM> and the second guide <NUM> allows for a relative translational movement between the first guide <NUM> and the second guide <NUM>, i.e., a position of one of the first guide <NUM> and the second guide <NUM> can be changed in translation one with respect to another.

As illustrated, first guide grooves 50A, 50B are provided on two opposite sides (corresponding to a portion of the outer periphery) of the first guide <NUM>. Similarly, second guide grooves 52A, 50B are provided on two opposite sides (corresponding to a portion of the outer periphery) of the second guide <NUM>.

As better illustrated in <FIG>, in some sample holders, the sample stage <NUM> includes a first connector <NUM>. The first connector <NUM> connects and slidably engages the first guide <NUM> with the second guide <NUM>.

In some sample holders, the first connector <NUM> can be made from a broad variety of material. For example, and without being limitative, the first connector <NUM> may be made from any solid material such made of polymers (such as and without being limitative vinyl, fiberglass, rigid polyvinyl chloride (PVC)), metals including metal alloys (such as and without being limitative aluminum and aluminium alloys), stainless steel, brass, copper, combinations thereof, or any other material that can be configured to form the first connector <NUM>. Of course, the first connector <NUM> have various geometrical configurations (i.e., size and dimensions). As depicted however, the first connector <NUM> comprises a U-shaped top portion and an inverted U-shape bottom portion. It will be readily understood that the first connector <NUM> could have a completely different shape, as long as it provides the appropriate mechanical connection between the first guide <NUM> and the second guide <NUM>.

In some sample holders, the second guide <NUM> can be slidably engageable with the first guide <NUM>. In this context, the first guide <NUM> can be immobile and can be for example affixed to the support frame <NUM> (or a portion thereof) and/or the base <NUM>, while the second guide <NUM> is slidably mounted to the first guide.

In the depicted sample holder of <FIG>, the first connector <NUM> includes a first pair of rails 56A, 56B. Each one of the first pair of rails 56A, 56B is engageable with a corresponding one of the first guide grooves 50A, 50B, such that the first connector <NUM> can slide (i.e., move in a relative translational movement) with respect to the first guide <NUM>.

In such sample holders, the first guide <NUM>, and more particularly its guide grooves 50A, 50B can be engaged with corresponding and complementary one of the first connector pair of rails 56A, 56B.

As illustrated, the first connector <NUM> also includes a first connector channel <NUM>. The first connector channel <NUM> is sized and configured to receive and hold the second guide <NUM> therein. In some sample holder, the second guide <NUM> is fixed to an inner portion of the first connector channel <NUM>. The second guide <NUM> can be fixed using known mechanical fasteners, such as, but not limited to nails, screws, clips, snap-lock mechanism, combination thereof, or any other element(s) or device(s) allowing to mechanically fix the second guide <NUM> to the first connector <NUM>.

As such, because the second guide <NUM> is fixed in the first connector channel <NUM>, when the first connector <NUM> slides with respect to the first guide <NUM> during a translation of the sample, then the second guide <NUM> can be translated along the x-axis (i.e., the direction parallel to the longitudinal axis of the first guide <NUM>).

The sample-contacting surface <NUM> is engageable to the second guide <NUM> and, as illustrated in the sample holder of <FIG>, the sample-contacting surface <NUM> is slidably engaged with the second guide <NUM>, i.e., in use, there is a relative translational movement between the sample-contacting surface <NUM> and the second guide <NUM>.

As illustrated, the second guide grooves 52A, 52B are provided on two opposite sides (corresponding to a portion of the outer periphery) of the second guide <NUM>.

In some sample holders, the sample stage <NUM> includes a second connector <NUM>. For example, and without being limitative, the second connector <NUM> can connect and slidably engage with the second guide <NUM>.

In some sample holders, the second connector <NUM> can be made from a broad variety of material and can be similar to the first connector <NUM>. For example, and without being limitative, the second connector <NUM> may be made from any solid material such made of polymers (such as and without being limitative vinyl, fiberglass, rigid polyvinyl chloride (PVC)), metals including metal alloys (such as and without being limitative aluminum and aluminium alloys), stainless steel, brass, copper, combinations thereof, or any other material that can be configured to form the second connector <NUM>. Of course, the second connector <NUM> have various geometrical configurations (i.e., size and dimensions). As depicted however, the second connector <NUM> comprises a U-shaped top portion and an inverted U-shape bottom portion. It will be readily understood that the second connector <NUM> could have a completely different shape, as long as it provides the appropriate mechanical connection between the second guide <NUM> and the sample-contacting surface <NUM>.

In some sample holders, the sample-contacting surface <NUM> can be slidably engageable with the second guide <NUM>.

In the depicted sample holder of <FIG>, the second connector <NUM> includes a second pair of rails 60A, 60B. Each one of the first pair of rails 60A, 60B is engageable with a corresponding one of the second guide grooves 52A, 52B, such that the second connector <NUM> can slide with respect to the second guide <NUM>.

In such sample holders, the second guide <NUM>, and more particularly its guide grooves 52A, 52B rails can be engaged with corresponding and complementary one of the second pair of rails 60A, 60B.

As illustrated, a platform <NUM> is provided on top of the second connector <NUM>. More particularly, the platform <NUM> can be fixed or attached to the second connector <NUM>. The platform <NUM> can be fixed using known mechanical fasteners, such as, but not limited to nails, screws, clips, snap-lock mechanism, combination thereof, or any other element(s) or device(s) allowing to mechanically fix the sample-contacting surface <NUM> to the second connector <NUM>.

As such, because the platform <NUM> is fixed to the second connector <NUM>, when the second connector <NUM> slides with respect to the second guide <NUM>, then the sample-contacting surface <NUM> can be translated along the y-axis (i.e., the direction parallel to the longitudinal axis of the second guide <NUM>).

As illustrated in <FIG> and <FIG>, the ball-mapping system <NUM> includes a motor assembly that comprises at least one motor <NUM>.

The motor <NUM>, which can be of any type or design, is configured to operate at least one of the second guide <NUM> and the sample-contacting surface <NUM>, i.e., to adjust or translate the second guide <NUM> or the sample-contacting surface <NUM> along a predetermined direction (e.g., the x-axis or the y-axis).

In some sample holders, the system <NUM> includes two motors <NUM>, each one of the motors <NUM> operating a respective one of the second guide <NUM> and the sample-contacting surface <NUM>. For example, in one sample holder, a first motor could be associated with the second guide <NUM> and be configured to engage the second guide <NUM> in a translational movement with respect to the first guide <NUM> by sliding the first connector <NUM> along the x-axis. In this sample holder, a second motor could be associated with the sample-contacting surface <NUM> and be configured to engage the sample-contacting surface <NUM> in a translational movement with respect to the second guide <NUM> by sliding the second connector <NUM> along the y-axis. Of course, the two motors could be interchanged, such that the first motor controls the translational movement along the y-axis, and the second motor controls the translational movement along the x-axis.

In some sample holders, the ball-mapping system <NUM> includes a control unit for controlling the motor assembly (e.g., the motor <NUM>) and directing movement of the sample stage <NUM>, such that X-ray diffraction data is collected at each one of the measurement points. For example, and without being limitative, the control unit can be embodied by a programmable computer, comprising at least one processor, a data storage system (including volatile and non-volatile memory and/or storage elements), at least one input device, and at least one output device. The programmable computer can, in some embodiments, executes computer programs that allows controlling the motor assembly and directing the movement of the sample stage <NUM>.

In other sample holders, the ball-mapping system <NUM> is connectable to an X-ray diffraction apparatus that generates X-ray radiation and to a control unit controlling the motor assembly and directing movement of the sample stage such that X-ray diffraction data is collected at each one of the measurement points.

In some sample holders, the ball-mapping system <NUM> can be configured such that the support frame <NUM> can rotate about the sample holder <NUM>. The rotation of the support frame <NUM> can be useful when it is necessary to orient the sample under investigation with the XRD apparatus. For example, and without being limitative, the rotation of the support frame <NUM>, and thus the sample, can allow to orient or align the crystal structure (or a portion thereof) of the sample with the XRD source and/or detector(s). The rotation can be provided, for example and without being limitative, by the supporting element <NUM>.

In these sample holders, the system <NUM> includes a first mounting bracket <NUM> and second mounting bracket <NUM>, each being slidably mounted to the base <NUM>, such that they can slide following the outer periphery <NUM> of the base <NUM>.

In some sample holders, the first and second mounting brackets <NUM>, <NUM> engage the support frame <NUM> in rotation with the base <NUM>.

In some sample holders, the first and second mounting brackets <NUM>, <NUM> are diametrically opposed and are each provided at a respective extremity of the first guide <NUM>. Of course, in alternate sample holders, the system could include other bracket(s) or similar components.

In these implementations, the sample-contacting surface <NUM> can then be translated along the x-axis and the y-axis and the support frame <NUM> can be rotated by an angle ϕ. As it has been previously presented, only one degree of freedom is generally adjustable at a time. For example, when the sample-contacting surface <NUM> is translated along the x-axis, it is not translated along y-axis and the support frame <NUM> is not rotated by an angle ϕ. Similarly, when the sample-contacting surface <NUM> is translated along the y-axis, it is not translated along x-axis and the support frame <NUM> is not rotated by an angle ϕ. Moreover, when the support frame <NUM> is rotated by an angle ϕ, the sample-contacting surface <NUM> is not translated along the x-axis and it is not translated along y-axis.

In the rotation implementations, the system <NUM> also includes at least one motor(s) configured to operate at least one of the second guide <NUM> and the sample-contacting surface <NUM>, i.e., to adjust or translate the second guide <NUM> or the sample-contacting surface <NUM> along a predetermined direction (e.g., x-axis or y-axis), but also to rotate the support frame <NUM> by an angle ϕ. It is to be noted that the center of rotation is near or at the center of the sample holder <NUM>.

In some sample holders, the motor assembly described above includes three motors, two of them being for operating a respective one of the second guide <NUM> and the sample-contacting surface <NUM>, and the other one to rotate support frame <NUM>. For example, in one sample holder a first motor could be associated with the second guide <NUM> and be configured to engage the second guide <NUM> in a translational movement with respect to the first guide <NUM> by sliding the first connector <NUM> along the x-axis. In this sample holder, a second motor could be associated with the sample-contacting surface <NUM> and be configured to engage the sample-contacting surface <NUM> in a translational movement with respect to the second guide <NUM> by sliding the second connector <NUM> along the y-axis. The third motor could be associated with the support frame <NUM>, the first mounting bracket <NUM> and/or the second mounting bracket <NUM> and be configured to engage the support frame <NUM> (or portion thereof), the first mounting bracket <NUM> and/or the second mounting bracket <NUM> in a rotational movement about the center of the sample holder <NUM>. Of course, the three motors could be interchanged, such that any one of the three motors could control the translational movement along the y-axis, another one of the three motors could control the translational movement along the x-axis and yet another one of the three motors could control the rotational movement.

As described above, the ball-mapping system <NUM> can be useful for maintaining a sample at a plurality of subsequent precise or predetermined locations during its characterization. Moreover, the adjustable size of the iris diaphragm <NUM> allows to apply an appropriate pressure onto the sample, such that the sample can roll on the sample-contacting surface <NUM>, having a sufficient coefficient of static friction, from one characterization position to another. The motor(s) <NUM> can advantageously position the sample-contacting surface <NUM> and keeps track of the absolute positioning, which requires ordered relative displacement of the first and second guides <NUM>,<NUM>. The ball-mapping system <NUM> can also be configured to provide different data from the same location on the sample. As a result of the combined abovementioned features, the ball-mapping system <NUM> can provide a substantially complete view of the surface conditions of the sample, thus revealing the poles or irregularities of the surface (e.g., consistency, high points and/or low points). It is to be noted that the ball-mapping system <NUM> is configured such that the characterization of the sample could be at least partially automated. Of course, one would readily understand that the ball-mapping system <NUM> can be used for mapping data of a sample before or after the sample has been used or cycled, for example for quality control.

Although the sample holders, of the sample holder, the sample stage and the motor, as well as their corresponding parts thereof consist of certain geometrical configurations and dimensions as explained and illustrated herein, not all of these components, geometries and dimensions are essential and thus should not be taken in their restrictive sense. It is to be understood, as also apparent to a person skilled in the art, that other suitable components and cooperation thereinbetween, as well as other suitable geometrical configurations, dimensions, shape, and the like may be used for the sample holder, the sample stage and the motor.

In accordance with the invention there is provided a method for mapping a ball-shaped sample.

Broadly described, the method includes steps of mounting the ball-shaped sample in a sample holder; contacting a portion of the ball-shaped sample with a sample-contacting surface of a sample stage; adjusting the sample stage along two mutually perpendicular axes such that the sample is in a characterization position; characterizing the ball-shaped sample with the X-ray diffraction apparatus; and moving the ball-shaped sample to another characterization position.

In one implementation, there is provided a method for mapping of a ball-shaped sample using X-ray diffraction. The method includes placing the ball-shaped sample on a sample-contacting surface; restricting movement of the ball-shaped sample with respect to the sample-contacting surface; translating the sample-contacting surface along a first axis and a second axis unparallel to the first axis, thereby causing the ball-shaped sample to rotate on the sample-contacting surface along of the first axis and the second axis to align a plurality of measurement points with an X-ray beam originating from an X-ray diffraction apparatus; and operating the X-ray diffraction apparatus to collect X-ray diffraction data at each one of the measurement points.

In some embodiments, the method, further includes rotating the sample holder by a predetermined angle to adjust a rotational degree-of-freedom of the sample holder.

In some embodiments, operating the X-ray diffraction apparatus includes collecting between about <NUM> to about <NUM> measurement points.

In some embodiments, the method includes generating a model representative of a surface of the ball-shaped sample and distributing virtual measurement points on the model, the virtual measurement points being representative of the measurement points. In some embodiments, the model is a polygon having a center coinciding with a center of the ball-shaped sample. In some embodiments, wherein the model is an icosahedron. Examples of models are illustrated in <FIG> and <FIG>, wherein the dots are representative of the positions of the measurement points at which X-ray diffraction data will be collected and analyzed.

In another implementation, there is provided a method for mapping a ball-shaped sample with an X-ray diffraction apparatus. The method includes steps of: mounting the ball-shaped sample in a sample holder; contacting a portion of the ball-shaped sample with a sample-contacting surface of a sample stage; adjusting the sample stage along two mutually perpendicular axes, including selectively engaging the sample stage in a sequential translation movement along the two mutually perpendicular axes and engaging the sample to roll on the sample-contacting surface along a respective one of the two mutually perpendicular axes at a time towards a characterization position; characterizing the ball-shaped sample with the X-ray diffraction apparatus while the sample is in the characterization position; and moving the ball-shaped sample to another characterization position.

In some embodiments, the step of adjusting the sample stage along two mutually perpendicular axes includes adjusting the sample stage along an x-axis and independently adjusting the sample stage along a y-axis.

In some embodiments, the sample holder has a rotational degree-of- freedom. The method can further include a step of adjusting the rotational degree-of-freedom of the sample holder with respect to the sample stage.

In some embodiments, adjusting the rotational degree-of-freedom includes rotating the sample holder by a predetermined angle.

In some embodiments, the method includes a step of engaging the sample to roll on the sample-contacting surface along a corresponding one of the two mutually perpendicular axes.

In some embodiments, the step of characterizing the ball-shaped sample includes predetermining locations of measurements on the ball-shaped sample by distributing measurement points on the ball-shaped sample.

In some embodiments, distributing the measurement points on the ball-shaped sample includes positioning said plurality of measurement points at predetermined latitudes of the ball-shaped sample, each one of the predetermined latitudes comprising a preselected number of measurement points. Such a distribution of measurement points is illustrated in <FIG>.

In some embodiments, the step of moving the ball-shaped sample to another characterization position includes calculating the polar coordinates of a first measurement point and of a second measurement point, the second measurement point being associated with said another characterization position; associating a curve trajectory between the first measurement point and the second measurement point, the curve trajectory defining an arc extending from the first measurement point to the second measurement point; converting the curve trajectory into a planar trajectory; decomposing the planar trajectory in an x-axis direction and in a y-axis direction; and independently changing a position of the sample stage along the x-axis direction and along the y-axis direction.

In some embodiments, the preselected latitudes each comprises the same number of preselected number of measurement points.

In some embodiments, the number of measurement points ranges from about <NUM> to about <NUM>.

In some embodiments, distributing the measurement points on the ball-shaped sample includes generating a polygonal model having a center coinciding with a center of the sample; positioning said plurality of measurement points on the vertices of the polygonal model. Such a distribution of measurement points is illustrated in <FIG>.

In some embodiments, the polygonal model is an icosahedron.

In some embodiments, the step of moving the ball-shaped sample to another characterization position includes calculating the polar coordinates of a first measurement point and of a second measurement point, the second measurement point being associated with said another characterization position; associating a curve trajectory between the first measurement point and the second measurement point, the curve trajectory defining an arc extending from the first measurement point to the second measurement point; converting the curve trajectory into a planar trajectory; decomposing the planar trajectory in an x-axis direction and in a y-axis direction; independently changing a position of the sample stage along the x-axis direction and along the y-axis direction.

In another implementation, there is provided a method for mapping a ball-shaped sample with an X-ray diffraction apparatus. The method includes of mounting the ball-shaped sample in a sample holder; contacting a portion of the ball-shaped sample with a sample-contacting surface of a sample stage; adjusting the sample stage along two translational degrees-of-freedom, including selectively engaging the sample stage in a sequential translation movement along the two translational degrees-of freedom towards a characterization position, such that:.

The method also includes steps of characterizing the ball-shaped sample with the X-ray diffraction apparatus while the sample is in the characterization position; and moving the ball-shaped sample to another characterization position.

In some embodiments, the first degree of freedom and the second degree of freedom are mutually perpendicular.

In some embodiments, the step of adjusting the sample stage along two translational degrees-of-freedom includes adjusting the first one of the two translational degrees-of-freedom; and subsequently adjusting the second one of the two translational degrees-of-freedom.

In some embodiments, the sample holder has a rotational degree-of- freedom, and the method further includes a step of adjusting the rotational degree-of-freedom of the sample holder with respect to the sample stage.

In some embodiments, the method further includes engaging the sample to roll on the sample-contacting surface along a corresponding one of the two translational degrees-of-freedom.

In some embodiments, distributing the measurement points on the ball-shaped sample includes positioning said plurality of measurement points at predetermined latitudes of the ball-shaped sample, each one of the predetermined latitudes comprising a preselected number of measurement points.

In some embodiments, the step of moving the ball-shaped sample to another characterization position includes calculating the polar coordinates of a first measurement point and of a second measurement point, the second measurement point being associated with said another characterization position; associating a curve trajectory between the first measurement point and the second measurement point, the curve trajectory defining an arc extending from the first measurement point to the second measurement point; converting the curve trajectory into a planar trajectory; decomposing the planar trajectory in an x-axis direction extending parallel to the first one of the two translational degrees-of-freedom and in a y-axis direction extending parallel to the first one of the two translational degrees-of-freedom; and independently changing a position of the sample stage along the x-axis direction and along the y-axis direction.

In some embodiments, the preselected latitudes each includes the same number of preselected number of measurement points.

In some embodiments, distributing the measurement points on the ball-shaped sample includes generating a polygonal model having a center coinciding with a center of the sample; and positioning said plurality of measurement points on the vertices of the polygonal model.

In some embodiments, the step of moving the ball-shaped sample to another characterization position includes calculating the polar coordinates of a first measurement point and of a second measurement point, the second measurement point being associated with said another characterization position; associating a curve trajectory between the first measurement point and the second measurement point, the curve trajectory defining an arc extending from the first measurement point to the second measurement point; converting the curve trajectory into a planar trajectory; decomposing the planar trajectory in an x-axis direction extending parallel to the first one of the two translational degrees-of-freedom and in a y-axis direction extending parallel to the second one of the two translational degrees-of-freedom; and independently changing a position of the sample stage along the x-axis direction and along the y-axis direction.

In some embodiments, the method relies on different data collection schemes. In one example, the method relies on a pseudo geodesic/solid angle position calculator based on a user input (e.g., the predetermined number of measurement points), for example in view of obtaining even spacing between neighboring measurement points.

Claim 1:
A method for mapping of a ball-shaped sample using X-ray diffraction, the method comprising:
placing the ball-shaped sample on a sample-contacting surface (<NUM>);
restricting movement of the ball-shaped sample with respect to the sample-contacting surface;
translating the sample-contacting surface (<NUM>) along a first axis and a second axis unparallel to the first axis, thereby causing the ball-shaped sample to rotate on the sample-contacting surface (<NUM>) along of the first axis and the second axis to align a plurality of measurement points with an X-ray beam originating from an X-ray diffraction apparatus; and operating the X-ray diffraction apparatus to collect X-ray diffraction data at each one of the measurement points.