Patent Description:
An amorphous alloy is a novel alloy material. Atoms in an inside structure of the amorphous alloy are in long-range disordered and short-range ordered arrangement. In its XRD pattern, diffuse scattering steamed bun peaks exist, but sharp peaks do not exist. Defects such as crystal boundary and dislocation of crystal materials do not exist in the amorphous alloy, and high strength, high hardness and excellent anti-corrosion performance are shown. A Zr-based amorphous alloy has very high apparent quality due to its self lubrication performance on the surface. Only elastic deformation occurs in a material deformation process with the performance of brittle fracture. In addition, the Zr-based amorphous alloy may be shaped in one step, and has greater design freedom. However, the Zr-based amorphous alloy has the following defects that firstly, the amorphous alloy has relatively high requirements on raw material purity in a preparation process, and in addition, raw material cost is obviously increased and the application range is greatly limited due to Zr and other rare earth elements in the amorphous alloy raw materials; secondly, the amorphous alloy does not have a crystal structure, and has no characteristics of crystal boundary, dislocation and the like, so that brittleness of the amorphous alloy is relatively great, toughness is reduced, and a fracture elongation rate is relatively small; and finally, a melting point of the amorphous alloy is relatively high, so that melting difficulty is increased.

The Cu-based microcrystal alloy has good crystallinity degree, but has a great number of nanoscale crystal grains, so that besides sharp peaks, wide and dispersed steamed bun peaks may also occur in its XRD pattern. Through occurrence of the Cu-based microcrystal alloy, the problems of great brittleness and high cost of the existing amorphous alloy are solved; additionally, original high-strength performance of the Cu-based microcrystal alloy is remained; toughness of the material is obviously improved; and product cost is obviously reduced. However, due to the existence of a crystal structure in the Cu-based microcrystal alloy, compared with the amorphous alloy, the Cu-based microcrystal alloy has lower strength and lower hardness. Additionally, due to lower yielding strength, the Cu-based microcrystal alloy has greater plastic deformation in a deformation process, and a prepared product has soft texture and easily deforms. In addition, like the amorphous alloy, the Cu-based microcrystal alloy also has a high melting point, and melting difficulty is increased.

Chinese application <CIT> by the same applicant discloses a Cu-based alloy of good mechanical strength, which includes, by percent of weight, Mn <NUM>-<NUM>%, Ni <NUM>-<NUM>%, Al <NUM>-<NUM>%, and at least one additional element of Ti, Cr, Fe, Zr and Sn at less than <NUM>%.

The invention aims at providing a Cu-based microcrystal alloy with performance between a Zr-based microcrystal alloy and an existing Cu-based microcrystal alloy and with the advantages of both the Zr-based microcrystal alloy and the existing Cu-based microcrystal alloy. The Cu-based microcrystal alloy solves the problems of raw material cost and preparation while meeting mechanical performance requirements of an alloy product. Fracture toughness of the alloy is increased, and a color and luster degree is improved.

According to a first aspect of the invention, the invention provides a Cu-based microcrystal alloy. Based on the total mass of the Cu-based microcrystal alloy as reference and through being metered in percentage by mass, the Cu-based microcrystal alloy includes the following elements:.

According to a second aspect of the invention, the invention provides a preparation method of a Cu-based microcrystal alloy. The method includes the step of sequentially melting and casting raw materials of the Cu-based microcrystal alloy, where through the composition of the raw materials of the Cu-based microcrystal alloy, the obtained Cu-based microcrystal alloy is the Cu-based microcrystal alloy provided by the invention.

The Cu-based microcrystal alloy provided by the invention has good comprehensive mechanical performance, relatively high strength and hardness, good shaping performance, high fracture toughness and no yielding phenomenon while the raw material cost is reduced. In addition, the Cu-based microcrystal alloy has a relatively low melting point and good casting performance. Additionally, compared with ordinary Cu-based microcrystal alloy, the Cu-based microcrystal alloy has relatively bright surface and good color and luster degree, and is favorable for later stage apparent treatment of a product.

Other aspects and advantages of the present invention will be given in the following description, some of which will become apparent from the following description or may be learned from practices of the present invention.

The following describes embodiments of the present invention in detail. The embodiments described below are exemplary, and are intended to explain the present invention and cannot be construed as a limitation to the present invention.

Based on the total mass of the Cu-based microcrystal alloy as reference and through being metered in percentage by mass, the Cu-based microcrystal alloy according to the invention includes the following elements:.

The disclosed Cu-based microcrystal alloy includes manganese (Mn). Manganese has a main effect of improving and enhancing hardness, strength, toughness and wear resistance of the alloy. Based on the total mass of the Cu-based microcrystal alloy and in terms of mass percentage, the Cu-based microcrystal alloy according to the invention includes <NUM> to <NUM> percent of manganese (preferably <NUM> to <NUM> percent).

The disclosed Cu-based microcrystal alloy includes aluminum (Al). Al and Cu may form an Al<NUM>Cu phase existing in most amorphous or amorphous and crystal phase alloys in an amorphous shaping process. Based on the total mass of the Cu-based microcrystal alloy and in terms of mass percentage, the Cu-based microcrystal alloy according to the invention includes <NUM> to <NUM> percent of aluminum (preferably <NUM> to <NUM> percent).

The disclosed Cu-based microcrystal alloy includes nickel (Ni). Nickel can maintain good plasticity and toughness of the alloy while improving the alloy strength, and achieves a certain improvement effect on anti-corrosion performance of the alloy. Based on the total mass of the Cu-based microcrystal alloy and in terms of mass percentage, the Cu-based microcrystal alloy according to the invention includes <NUM> to <NUM> percent of nickel (preferably <NUM> to <NUM> percent).

The disclosed Cu-based microcrystal alloy includes titanium (Ti). Through addition of titanium, not only are flowability and cutting performance of the alloy improved, but also crack resistance of the alloy is improved. Based on the total mass of the Cu-based microcrystal alloy and in terms of mass percentage, the Cu-based microcrystal alloy according to the invention includes <NUM> to <NUM> percent of titanium (preferably <NUM> to <NUM> percent).

The disclosed Cu-based microcrystal alloy includes zirconium (Zr) and silicon (Si). Through addition of zirconium, hardness and elastic strain of the alloy are improved. Through silicon, alloy crystal grains are finer, steamed bun peaks are obviously coarsened, and the alloy directly fractures without yielding in a stretching process. Through simultaneous addition of zirconium and silicon, an integral melting point of the alloy is reduced, tensile strength is increased, and a color and luster degree is relatively good. Based on the total mass of the Cu-based microcrystal alloy and in terms of mass percentage, the Cu-based microcrystal alloy according to the invention includes <NUM> to <NUM> percent of zirconium (preferably <NUM> to <NUM> percent), and <NUM> to <NUM> percent of silicon (preferably <NUM> to <NUM> percent).

According to one preferable embodiment of the Cu-based microcrystal alloy according to the invention, based on the total mass of the Cu-based microcrystal alloy and in terms of mass percentage, the Cu-based microcrystal alloy includes the following elements:.

The Cu-based microcrystal alloy according to the invention may be prepared by various common methods. Particularly, raw materials of the Cu-based microcrystal alloy are sequentially molten and cast, wherein through the composition of the raw materials of the Cu-based microcrystal alloy, the obtained Cu-based microcrystal alloy is the Cu-based microcrystal alloy of the invention. Particularly, purity of the raw materials of the Cu-based microcrystal alloy is higher than <NUM> percent, preferably higher than <NUM> percent.

The invention is illustrated in details in combination with embodiments hereafter, but the scope of the invention is not limited thereto.

All samples in the following embodiments and contrast embodiments are subjected to a Vickers hardness test based on a digital Vickers hardness tester with a model being HVS-10Z according to GB/T <NUM>-<NUM>.

A tensile performance (yielding strength, tensile strength and elastic strain) test is performed based on a microcomputer control electronic universal (tension) test machine with a model being CMT5105 according to GBT <NUM>-<NUM>.

In the following embodiments and contrast embodiments, the molten and cast Cu-based microcrystal alloy is subjected to die casting into molds of different structures. Obtained samples are subjected to visual inspection, and shaping performance is evaluated according to the following standards:.

Embodiments <NUM>-<NUM> are used for illustrating the invention.

Calculation is respectively performed according to alloy composition in Table <NUM>: Mn (with purity being <NUM> percent), Al (with purity being <NUM> percent), Ni (with purity being <NUM> percent), Ti (with purity being <NUM> percent), Zr (with purity being <NUM> percent), Si (with purity being <NUM> percent) and Cu (with purity being <NUM> percent) are weighed.

Alloy raw materials are put into a vacuum melting furnace. The vacuum melting furnace is subjected to vacuum pumping to a value below <NUM> Pa. Argon gas is introduced. A furnace body is preheated for <NUM> at <NUM> kW, and is then heated to <NUM> DEG C at <NUM> kW. Casting is performed after heat insulation for about <NUM>. Then, die casting is performed in a die casting machine at die casting temperature of <NUM> DEG C. The number of pressure turns is <NUM> Q. Heat insulation time is <NUM>. A primary injection initial point is <NUM>, and a secondary injection initial point is <NUM>. Therefore, a die cast body of the Cu-based microcrystal alloy of the invention is obtained.

Hardness, yielding strength, tensile strength and elastic strain of the prepared Cu-based microcrystal alloy are tested, and results are listed in Table <NUM>.

A die cast body of a Cu-based microcrystal alloy is prepared by a method identical to a method according to Embodiment <NUM>. The difference is that raw materials of the Cu-based microcrystal alloy are prepared according to the composition in Table <NUM>.

A die cast body of a Cu-based microcrystal alloy is prepared by a method identical to the method according to Embodiment <NUM>. The difference is that raw materials of the Cu-based microcrystal alloy are prepared according to the composition in Table <NUM>.

Note: ratios in Table <NUM> are metered in percentage by mass, and additionally, the balance is Cu and unavoidable impurities.

Results of Table <NUM> show that the Cu-based microcrystal alloy according to the invention has good comprehensive mechanical performance, has no yielding phenomenon and has relatively high hardness, tensile strength and elastic strain under good shaping conditions.

Contrast Embodiment <NUM> is an existing Cu-based microcrystal alloy. Through comparing Embodiment <NUM> with Contrast Embodiment <NUM>, it can be seen that the existing Cu-based microcrystal alloy has a yielding phenomenon, and has relatively low hardness, strength and elastic strain.

Through comparing Embodiment <NUM> with Contrast Embodiment <NUM>, it can be seen that when content of titanium in the Cu-based microcrystal alloy is too high, the hardness and strength of a Cu-based microcrystal alloy material are reduced, and shaping performance becomes poor.

Through comparing Embodiment <NUM> with Contrast Embodiment <NUM>, it can be seen that when content of zirconium in the Cu-based microcrystal alloy is too high, the Cu-based microcrystal alloy material is brittle. A crystallization phenomenon is serious. Yielding is generated. The shaping performance of the material is relatively poor.

Through comparing Embodiment <NUM> with Contrast Embodiment <NUM> and Contrast Embodiment <NUM>, it can be seen that when no silicon exists in the Cu-based microcrystal alloy or content of silicon is too low, the hardness and tensile strength of the Cu-based microcrystal alloy are reduced. The material yielding occurs. Texture is soft. Deformation easily occurs.

Through comparing Embodiment <NUM> and with Contrast Embodiment <NUM>, it can be seen that when the content of silicon in the Cu-based microcrystal alloy is too high, the hardness and tensile strength of the Cu-based microcrystal alloy are increased, but thermal shock resistance of the material becomes poor, and shaping cannot be realized.

The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the specific details in the above embodiments. Various simple variations may be made to the technical solutions of the present invention within the scope of the appended claims.

It should be further noted that the specific technical features described in the above specific embodiments may be combined in any suitable manner without contradiction. To avoid unnecessary repetition, various possible combinations are not further described in the present description.

In addition, the various embodiments of the present invention may be combined without departing from the present invention, and such combinations shall also fall within the scope of the present invention as defined by the appended claims.

In the descriptions of this specification, descriptions using reference terms "an embodiment", "some embodiments", "an example", "a specific example", or "some examples" mean that specific characteristics, structures, materials, or features described with reference to the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic descriptions of the foregoing terms do not necessarily directed at a same embodiment or example. In addition, the described specific features, structures, materials, or features can be combined in a proper manner in any one or more embodiments or examples. In addition, in a case that is not mutually contradictory, a person skilled in the art can combine or group different embodiments or examples that are described in this specification and features of the different embodiments or examples.

Claim 1:
A Cu-based microcrystal alloy, wherein based on a total mass of the Cu-based microcrystal alloy and in terms of mass percentage, the Cu-based microcrystal alloy comprises:
<NUM> to <NUM> percent of Mn,
<NUM> to <NUM> percent of Al,
<NUM> to <NUM> percent of Ni,
<NUM> to <NUM> percent of Ti,
<NUM> to <NUM> percent of Zr,
<NUM> to <NUM> percent of Si,
the balance being Cu.