Method for improving elastic property of Au-Pt alloy

Abstract

The invention relates to the technical field of Au-Pt alloy, in particular to a method for improving the elastic property of Au-Pt alloy. The method specifically comprises the steps that an optimized supercell model of the Au-Pt binary alloy with the lowest energy is obtained, and Au-Pt-M alloy supercell models of different alloying systems are established; carrying out ground state energy calculation so as to determine preferred occupation of alloying atoms, and obtaining an Au-Pt-M alloy optimized supercell model; carrying out elastic property calculation to obtain elastic property data of the Au-Pt-M alloy optimized supercell models of different alloying systems; and alloying elements with more remarkable improvement of the elastic property are screened out. According to the method, the performance of the alloy is accurately predicted under the condition that actual synthetic materials are not needed, and the experiment cost is greatly reduced; the research and development efficiency is greatly improved; alloying of various elements is allowed and is not limited by experimental conditions, and the elastic property of the alloy is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of Au-Pt alloys, and in particular to a method for improving the elastic properties of Au-Pt alloys. Background Art

[0002] Au-Pt alloys, due to their high density, ultra-low magnetic susceptibility, excellent corrosion resistance, and exceptional biocompatibility, have been widely used in biomedical devices. Despite these advantages, Au-Pt alloys suffer from relatively low hardness and modulus compared to commonly used biomedical metals such as stainless steel, Ti-6Al-4V, and Co-Cr alloys, significantly hindering their application in vascular stents, aneurysm clips, and other medical devices. Therefore, improving the elastic properties of Au-Pt alloys can ensure that they can better withstand mechanical stress and deformation under physiological conditions, thereby meeting the stringent requirements for structural stability and durability in biomedical applications.

[0003] Microalloying provides an option for improving alloy properties. To date, a few studies have explored the effect of alloying on the mechanical properties of Au-Pt alloys. For example, strengthening elements mainly include transition metal elements such as Ag, Cu, Pd, Nb and Zn. However, these studies are still insufficient to reasonably analyze the impact on the mechanical properties of more complex ternary alloy systems, which makes it difficult to further optimize the alloy properties. In addition, the high cost of Au-Pt alloys poses a challenge to industrial production and limits its promotion in large-scale biomedical applications. At the same time, there are various uncontrollable experimental variables in the experiment, which limits the accuracy and repeatability of the experimental results. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a method for improving the elastic properties of Au-Pt alloy.

[0005] To achieve the above objectives, the technical solutions of the present invention are as follows.

[0006] The present invention provides a method for improving the elastic properties of Au-Pt alloy, comprising the following steps:

[0007] A supercell model of the Au-Pt binary alloy was established, and the structure of the supercell model of the Au-Pt binary alloy was optimized to obtain the optimized supercell model of the Au-Pt binary alloy with the lowest energy; alloying atoms were introduced into the optimized supercell model of the Au-Pt binary alloy to establish the Au-Pt-M alloy supercell model; the ground state energy of the Au-Pt-M alloy supercell model was calculated, and the preferential occupation of the alloying atoms was determined based on the lowest ground state energy to obtain the optimized supercell model of the Au-Pt-M alloy; the binding energy and elastic property data of the optimized supercell model of the Au-Pt-M alloy were obtained to screen out alloying elements with more significant improvement in elastic properties.

[0008] Preferably, the method for establishing the Au-Pt-M alloy supercell model is:

[0009] The replacement atomic sites of the optimized supercell model of the Au-Pt binary alloy are obtained, and the alloying atoms are sequentially replaced with multiple replacement atomic sites, thereby introducing the alloying atoms into the optimized supercell model of the Au-Pt binary alloy to establish the Au-Pt-M alloy supercell model.

[0010] The present invention primarily replaces 96 substitutional atomic sites with alloying elements one by one to find the optimal alloying atomic substitution site. The structure of the Au-Pt-M alloy supercell model is then optimized under the optimal alloying atomic substitution site.

[0011] Preferably, M represents an alloying atom; the alloying atom is Zr, Nb, Mo, Hf, Ta, W, Re, Cu, Pd, Ir, Zn, Y, Ru, Rh, Ag, Cd, La, Ce or Os.

[0012] In the present invention, a disordered solid solution model of Au-Pt alloy is established, a common alloying element M is selected, and the binding energy and elastic property data of Au-Pt and Au-Pt-M alloys are calculated based on first principles. Key performance parameters including bulk modulus B, shear modulus G, Young's modulus E, Poisson's ratio v, Pugh value B / G and hardness Hv are obtained.

[0013] The results show that the binding energy of the Zr, Nb, Mo, Hf, Ta, W, and Re alloying system is significantly lower than that of other alloying systems, indicating that its thermodynamic properties are more stable. Furthermore, non-face-centered cubic (FCC) elements, such as Zr, Nb, Mo, Hf, Ta, W, and Re, significantly enhance the elastic properties of the alloy compared to face-centered cubic elements, such as Cu, Pd, and Ir. Therefore, Zr, Nb, Mo, Hf, Ta, W, and Re are excellent alloying elements for improving the elastic properties of Au-Pt alloys, providing a theoretical basis for optimizing the properties of Au-Pt alloys.

[0014] Preferably, the method for determining the preferred position of alloying atoms is as follows:

[0015] The ground state energy of the Au-Pt-M alloy supercell model was calculated to obtain the total ground state energy of the Au-Pt-M alloy supercell model at the corresponding substitutional atomic sites of different alloying atoms. Taking the lowest ground state energy as the standard, the substitutional atomic sites of Au atoms in which alloying atoms are more likely to occupy were determined as the preferential occupancy sites of alloying atoms, and the optimized supercell model of the Au-Pt-M alloy was established.

[0016] Preferably, the method for obtaining the binding energy of the Au-Pt-M alloy optimized supercell model is as follows:

[0017] According to the obtained Au-Pt-M alloy optimized supercell model, the total ground state energy of the Au-Pt-M alloy supercell model, the total number of Au, Pt and M atoms, and the sum of the ground state energies of Au, Pt and M atoms in the solid state are obtained; the binding energy of the Au-Pt-M alloy optimized supercell model is obtained by subtracting the sum of the ground state energies of Au, Pt and M atoms in the solid state from the total ground state energy of the Au-Pt-M alloy supercell model, and then dividing it by the total number of Au, Pt and M atoms.

[0018] Preferably, the calculation formula for the binding energy of the Au-Pt-M alloy optimized supercell model is as follows:

[0019]

[0020] Where ΔH represents the binding energy of the optimized supercell model of Au-Pt-M alloy; E tot represents the total ground state energy of the Au-Pt-M alloy supercell model; represents the ground state energy of a single Au atom in the solid state; represents the ground state energy of a single Pt atom in the solid state; represents the ground state energy of a single M atom in the solid state; N Au represents the number of Au atoms; N Pt represents the number of Pt atoms; N M represents the number of M atoms.

[0021] The present invention analyzes the thermodynamic stability and elastic properties of different Au-Pt-M based ternary alloys by combining energy and elastic property data, screens out suitable alloying elements, and assists in the design and development of new Au-Pt-M ternary alloy materials.

[0022] Preferably, the method for obtaining elastic property data of the Au-Pt-M alloy optimized supercell model is:

[0023] The elastic properties of the Au-Pt-M alloy optimized supercell model were calculated, and the elastic properties data of the Au-Pt-M alloy optimized supercell model with different alloying atoms were obtained.

[0024] Preferably, the elastic properties include bulk modulus, shear modulus, Young's modulus, Poisson's ratio, B / G value and Vickers hardness value.

[0025] Preferably, the method for selecting alloying elements that can significantly improve elastic properties is:

[0026] By comparing the binding energy and elastic constants of the optimized supercell model of Au-Pt-M alloy, alloying elements with relatively low binding energy and relatively high elastic constants are obtained.

[0027] Preferably, the optimized supercell model of the Au-Pt binary alloy contains 96 atoms, of which 72 are Au atoms and 24 are Pt atoms.

[0028] Beneficial effects of the present invention:

[0029] 1. The present invention mainly involves three stages of research: introducing alloying atoms into the optimized supercell model of the Au-Pt binary alloy to establish an Au-Pt-M alloy supercell model; determining the preferential occupation of alloying atoms through ground state energy calculation, thereby determining the optimal atomic replacement site of the alloying atomic bomb; and systematically analyzing the effects of different alloying elements on the binding energy and elastic properties of the optimized supercell model of the Au-Pt-M alloy by comparing binding energy and elastic properties data, thereby screening out alloying elements with more stable thermodynamic properties and significantly improved elastic properties.

[0030] 2. The method of the present invention accurately predicts alloy properties without the need for actual material synthesis, significantly reducing experimental costs. Furthermore, the method of the present invention rapidly delivers results through computational simulation, significantly improving the research and development efficiency of Au-Pt-M ternary alloy materials. It allows for the alloying of multiple elements without being restricted by experimental conditions, offering design flexibility and effectively improving the elastic properties of the alloy.

[0031] 3. The present invention utilizes the selected alloying elements to strengthen the Au-Pt alloy, and can establish a quasi-random disordered solid solution model of the Au-Pt-M ternary alloy, thereby promoting the further development and application of the alloy in high-end medical devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of the optimized supercell model of the 96-atom Au72Pt24 alloy after structural optimization. Yellow atoms represent Au, gray atoms represent Pt, the first 72 substitutional atomic sites are Au atoms, and the last 24 substitutional atomic sites are Pt atoms.

[0033] Figure 2 This is the ground state energy heat map of the Au-Pt-M alloy system after different alloying elements replace 96 substitution atomic sites.

[0034] Figure 3 It is the binding energy of the optimized supercell model of Au72Pt24 alloy and the optimized supercell model of Au71MPt24 alloy.

[0035] Figure 4 The radar diagram of the elastic performance data of the Au72Pt24 alloy optimized supercell model and the Au71MPt24 alloy optimized supercell model. 11 Radar chart of the data; (b) is c 12 Radar chart of the data; (c) is c 44 Radar plot of the data; (d) is a radar plot of bulk modulus; (e) is a radar plot of shear modulus; (f) is a radar plot of Young's modulus; (g) is a radar plot of Pugh value; (h) is a radar plot of Poisson's ratio; and (i) is a radar plot of Vickers hardness. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0037] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of the present invention.

[0038] The technical solution of the present invention is further described below through specific embodiments.

[0039] In the following examples, the methods described are conventional methods unless otherwise specified; the reagents and materials described are commercially available unless otherwise specified.

[0040] A method for improving the elastic properties of Au-Pt alloy comprises the following steps:

[0041] Step 1: Establish a supercell model of the Au-Pt binary alloy, and perform structural optimization on the supercell model of the Au-Pt binary alloy to obtain an optimized supercell model of the Au-Pt binary alloy with the lowest energy.

[0042] Step 1.1, establish a supercell model of Au-Pt binary alloy.

[0043] To construct a supercell model of an Au-Pt binary alloy, the following steps are performed: First, determine the crystal structure type of the Au-Pt binary alloy, typically face-centered cubic (fcc). Then, use a special quasi-random structure method to construct a 96-atom supercell model of the Au-Pt binary alloy. The atomic coordinates and lattice parameters of the generated supercell model are saved in a POSCAR file.

[0044] Specifically, the supercell model of the Au-Pt binary alloy is achieved by constructing a larger periodic supercell unit and introducing a specific atomic arrangement in the supercell unit to simulate an ordered or disordered Au-Pt alloy structure. The embodiment of the present invention mainly adopts a special quasi-random structure modeling method to establish a 96-atom supercell model of the Au-Pt binary alloy. By structurally optimizing the supercell model of the Au-Pt binary alloy, an optimized supercell model of the Au-Pt binary alloy with the lowest energy is obtained. The optimized supercell model has the lowest energy and the most stable structure.

[0045] Step 1.2, structurally optimize the supercell model of the Au-Pt binary alloy to obtain the optimized supercell model of the Au-Pt binary alloy with the lowest energy.

[0046] The method for structural optimization of the supercell model of Au-Pt binary alloy is:

[0047] The plane wave cutoff energy is set to 450 eV and the energy convergence condition is EDIFF = 1.0 × 10 -5 eV, the force convergence condition is The K point in the Brillouin zone was set to 3×7×1; the maximum number of optimization steps was set to 300, the conjugate gradient method was used, and ion relaxation and lattice relaxation were turned on to make the total energy of the system and the atomic force meet the preset convergence criteria, and the optimized supercell model of the Au-Pt binary alloy with the lowest energy was obtained.

[0048] In the present invention, all first-principles calculations are performed using the Vienna Analog Simulation Package, abbreviated as VASP. Perdew-Burke-Ernzerhof, abbreviated as PBE, is also known as Perdew-Burke-Ernzerhof in Chinese. The generalized gradient approximation method, abbreviated as GGA, is used to describe the exchange interaction between electrons. The projected augmented wave method is used to describe the pseudopotential, and the plane wave cutoff energy is set to 450 eV. For the first Brillouin zone integration, the reciprocal space of all calculations uses the Gamma K-point scheme with 3×7×1 K points; ensure that the K-point distribution matches the geometry of the supercell model.

[0049] When performing system architecture optimization calculations, the TAG parameter in the INCAR file is set to NSW=300, indicating a maximum number of optimization steps of 300. Ion relaxation IBRION=2 and lattice relaxation ISIF=3 are enabled, and the convergence criteria are set to: Energy convergence condition EDIFF=1.0×10 -5 eV, the force convergence condition is Based on first-principles calculations, the present invention employs the conjugate gradient method to iteratively adjust atomic positions and lattice parameters, ensuring that the total system energy and atomic forces meet preset convergence criteria. Based on this, the supercell model of the Au-Pt binary alloy is structurally optimized, resulting in an optimized supercell model with the lowest energy and most stable structure.

[0050] Figure 1 This is a schematic diagram of the optimized supercell model of the 96-atom Au72Pt24 alloy after structural optimization. Yellow atoms represent Au, gray atoms represent Pt, the first 72 substitutional atomic sites are Au atoms, and the last 24 substitutional atomic sites are Pt atoms.

[0051] Step 2: Introduce alloying atoms into the optimized supercell model of the Au-Pt binary alloy to establish an Au-Pt-M alloy supercell model.

[0052] The method to establish the Au-Pt-M alloy supercell model is:

[0053] Obtain replacement atomic sites of an optimized supercell model of an Au-Pt binary alloy, and sequentially replace multiple replacement atomic sites with alloying atoms, thereby introducing alloying atoms into the optimized supercell model of the Au-Pt binary alloy to establish an Au-Pt-M alloy supercell model. Here, M represents an alloying atom; the alloying atom is selected from Zr, Nb, Mo, Hf, Ta, W, Re, Cu, Pd, Ir, Zn, Y, Ru, Rh, Ag, Cd, La, Ce, or Os.

[0054] Since the Au-Pt binary alloy has a disordered structure, the chemical environment of each atom in the Au-Pt binary alloy system is different. Therefore, the embodiment of the present invention replaces the 96 replacement atomic sites of the optimized supercell model of the Au-Pt binary alloy with alloying atoms, thereby establishing Au-Pt-M alloy supercell models of different alloying systems.

[0055] Step 3: Calculate the ground state energy of the Au-Pt-M alloy supercell model, determine the preferential position of the alloying atoms based on the lowest ground state energy, and obtain the optimized supercell model of the Au-Pt-M alloy.

[0056] In the embodiment of the present invention, the ground state energy can be directly obtained by static calculation after structural optimization. When performing the ground state energy calculation, the parameters of TAG in the INCAR file are set to NSW=0 and IBRION=-1. The convergence standard is set as follows: the energy convergence condition is EDIFF=1.0×10 -5 eV, the force convergence condition is

[0057] In an embodiment of the present invention, in order to calculate the ground state energy of a single atom in a solid state, the atom is placed in a larger non-cubic box to break its initial symmetry.

[0058] The method for determining the preferred occupancy of alloying atoms is as follows:

[0059] The ground state energy of the Au-Pt-M alloy supercell model was calculated to obtain the total ground state energy of the Au-Pt-M alloy supercell model at the corresponding substitutional atomic sites of different alloying atoms. Taking the lowest ground state energy as the standard, the substitutional atomic sites of Au atoms in which alloying atoms are more likely to occupy were determined as the preferential occupancy sites of alloying atoms, and the optimized supercell model of the Au-Pt-M alloy was established.

[0060] Figure 2 This is the ground state energy heat map of the system after different alloying elements replace 96 substitution atomic sites.

[0061] Figure 2 The results show that the total ground-state energy of the Au-Pt-M alloy supercell model after Au atom substitution is significantly lower than that of the Pt atom substitution, as evidenced by a darker color in the ground-state energy heat map. Furthermore, alloying atoms prefer to replace Au atomic sites in the lattice. Among the 72 Au atomic sites, the system's total ground-state energy is lowest when most alloying atoms occupy substitution site 12. This substitution site, designated site 12, indicates that site 12 is the optimal alloying site.

[0062] Step 4: Obtain the binding energy and elastic performance data of the Au-Pt-M alloy optimized supercell model to screen out alloying elements that have more significant improvements in elastic properties.

[0063] Step 4.1, obtain the binding energy of the optimized supercell model of Au-Pt-M alloy.

[0064] The method for obtaining the binding energy of the Au-Pt-M alloy optimized supercell model is as follows:

[0065] According to the obtained Au-Pt-M alloy optimized supercell model, the total ground state energy of the Au-Pt-M alloy supercell model, the total number of Au, Pt and M atoms, and the sum of the ground state energies of Au, Pt and M atoms in the solid state are obtained; the binding energy of the Au-Pt-M alloy optimized supercell model is obtained by subtracting the sum of the ground state energies of Au, Pt and M atoms in the solid state from the total ground state energy of the Au-Pt-M alloy supercell model, and then dividing it by the total number of Au, Pt and M atoms.

[0066] The calculation formula of the binding energy of the Au-Pt-M alloy optimized supercell model is as follows:

[0067]

[0068] Where ΔH represents the binding energy of the optimized supercell model of Au-Pt-M alloy; E tot represents the total ground state energy of the Au-Pt-M alloy supercell model; represents the ground state energy of a single Au atom in the solid state; represents the ground state energy of a single Pt atom in the solid state; represents the ground state energy of a single M atom in the solid state; N Au represents the number of Au atoms; N Pt represents the number of Pt atoms; N M represents the number of M atoms. represents the sum of the ground state energies of Au, Pt, and M atoms in the solid state. (N Au +N Pt +N M ) represents the total number of Au, Pt and M atoms.

[0069] As can be seen from the calculation formula of the binding energy of the Au-Pt-M alloy supercell model, the binding energy of the Au-Pt-M alloy optimized supercell model is calculated by subtracting the sum of the ground state energies of the constituent atoms from the total ground state energy of the Au-Pt-M alloy supercell model, and then dividing it by the total number of constituent atoms. This calculation method ensures that the energy change of each atom in the alloy is relative to its isolated state.

[0070] Step 4.2: Obtain elastic performance data of the optimized supercell model of Au-Pt-M alloy.

[0071] The method to obtain the elastic properties data of the optimized supercell model of Au-Pt-M alloy is:

[0072] The elastic properties of the Au-Pt-M alloy optimized supercell model were calculated, and the elastic properties data of the Au-Pt-M alloy optimized supercell model with different alloying atoms were obtained.

[0073] Specifically, the elastic properties include bulk modulus, shear modulus, Young's modulus, Poisson's ratio, B / G value and Vickers hardness value.

[0074] In the embodiment of the present invention, the elastic constants of the Au-Pt-M alloy optimized supercell model with different alloying atoms are obtained by calculation to illustrate the change law of the elastic properties of the Au-Pt-M alloy optimized supercell model with different alloying atoms.

[0075] The elastic properties are calculated as follows:

[0076]

[0077] Pugh = B / G;

[0078]

[0079] Wherein, B represents bulk modulus; G represents shear modulus; E represents Young's modulus; v represents Poisson's ratio; Pugh represents Pugh's ratio; Hv represents Vickers hardness; s 11 represents the flexibility constant of the alloying atoms in the preferred position 11; s 12 represents the flexibility constant of the alloying atoms in the preferred position 12; s 44 represents the flexibility constant of the alloying atoms in the preferred position 44; c 11 represents the elastic constant of the alloying atoms occupying the preferred site 11; c 12 represents the elastic constant of the alloying atoms in the preferred position 12; c 44 represents the elastic constant of the alloying atoms occupying the preferred site 44.

[0080] In the embodiment of the present invention, s ij represents the flexibility constant of the preferred site ij of the alloying atom; c ij Indicates the elastic constant of the preferred site ij of the alloying atom. In the cubic system, there are three elastic constants, namely c 11 、c 12 and c 44 Therefore, for Au-Pt alloy, the preferred positions ij represent 11, 12, and 44. The flexibility constant is the matrix element of the flexibility matrix; the elastic constant is the matrix element of the elastic matrix. The flexibility matrix s is the inverse matrix of the elastic matrix c, that is, s = c -1 .

[0081] The Pugh ratio, also known as the Pugh value in Chinese, is the ratio of the shear modulus to the bulk modulus, denoted as B / G. The B / G value measures the toughness and brittleness of the Au-Pt-M alloy. When B / G is greater than 1.75, the Au-Pt-M alloy tends to undergo ductile fracture; when B / G is ≤1.75, the Au-Pt-M alloy tends to undergo brittle fracture.

[0082] In step 4.3, the binding energy and elastic constants of the supercell model are optimized based on the obtained Au-Pt-M alloy to screen out alloying elements that have more significant improvements in elastic properties.

[0083] The method to select alloying elements that can improve elastic properties more significantly is:

[0084] By comparing the binding energy and elastic constants of the optimized Au-Pt-M alloy supercell model, alloying elements with relatively low binding energy and relatively high elastic constants were identified. This allowed the selection of an optimized Au-Pt-M alloy supercell model with more stable thermodynamic properties and significantly improved elastic performance.

[0085] The relatively low binding energy indicates that the thermodynamic properties of the Au-Pt-M alloy supercell model of the corresponding alloying system are more stable. Based on this, the thermodynamic stability of the alloying system is determined.

[0086] Figure 3 It is the binding energy of the optimized supercell model of Au72Pt24 alloy and the optimized supercell model of Au71MPt24 alloy. Figure 3 The results show that the binding energy of the Au-Pt-M alloy system is lower when the alloying elements Zr, Nb, Mo, Hf, Ta or W are introduced into the Au72Pt24 alloy matrix, which indicates that the alloying of these elements will make the thermodynamic properties of the Au-Pt-M alloy system more stable.

[0087] The screening criteria of the embodiment of the present invention are Figure 3 The alloying atoms with relatively low binding energy are screened out from the binding energy curve, especially the alloying atoms with binding energy lower than -3.85eV / atom.

[0088] Figure 4 The radar diagram of the elastic performance data of the Au72Pt24 alloy optimized supercell model and the Au71MPt24 alloy optimized supercell model. 11 Radar chart of the data; (b) is c 12 Radar chart of the data; (c) is c 44 Radar plot of the data; (d) is a radar plot of bulk modulus; (e) is a radar plot of shear modulus; (f) is a radar plot of Young's modulus; (g) is a radar plot of Pugh value; (h) is a radar plot of Poisson's ratio; and (i) is a radar plot of Vickers hardness.

[0089] Figure 4In each graph, the different colored areas represent different alloy systems, with red representing the Au72Pt24 alloy and blue representing the Au71MPt24 alloy. The numerical values ​​in the graphs indicate how these elastic properties change with the addition of different alloying elements. These graphs allow for a visual comparison of the effects of different alloying elements on the elastic properties of Au-Pt alloys.

[0090] Figure 4 In Figures (a) to (c), c 11 、c 12 and c 44 It shows that all alloy systems meet the Born-Huang mechanical stability criterion.

[0091] Figure 4 Figure (d) shows that typical body-centered cubic (BCC) atoms are Nb, Mo, or W, hexagonal close-packed (HCP) atoms are Zr, Ru, Hf, Re, or Os, and face-centered cubic (FCC) atoms are Rh, Pd, or Ir. Typical body-centered cubic (BCC), hexagonal close-packed (HCP), and face-centered cubic (FCC) atoms all increase the bulk modulus of the Au-Pt alloy to varying degrees, with Os having the most significant effect on the alloy's deformation resistance.

[0092] Figure 4 Figures (e) to (f) show that the shear modulus and Young's modulus are highly correlated. Alloying elements such as Cu, Zn, Y, Ag, and Cd increase the stiffness and shear resistance of the alloy to a certain extent, and the strengthening effect of Re is the most significant.

[0093] Figure 4 Figures (g) to (i) show that the addition of alloying elements increases hardness while decreasing the plasticity of the alloy, indicating that the Au-Pt alloy itself has excellent plasticity. Therefore, compared with FCC atoms such as Cu, Pd, or Rh, non-FCC atoms such as Zr, Nb, Mo, Hf, Ta, W, or Re are more effective in improving the elastic properties of the material.

[0094] The embodiments of the present invention are combined by comparison Figure 3 The binding energy and Figure 4 The elastic properties data of the alloy are used to screen out alloying elements with relatively low binding energy and more significant improvement in elastic properties. Figure 3 and Figure 4 The results show that Zr, Nb, Mo, Hf, Ta or W are excellent alloying elements that can stabilize the alloy system and significantly improve the elastic properties of the alloy.

[0095] In summary, the embodiments of the present invention provide a method for improving the elastic properties of Au-Pt alloys. By calculating the binding energy and elastic performance data of the Au-Pt-M alloy optimized supercell model using first principles, the effects of different alloying elements on the binding energy and elastic performance data of the Au-Pt-M alloy optimized supercell model are systematically analyzed. Compared with the prior art, the embodiments of the present invention establish a quasi-random disordered solid solution model of the Au-Pt-M ternary alloy and screen out the alloying elements Zr, Nb, Mo, Hf, Ta, W, and Re that have more stable thermodynamic properties and significantly improved elastic properties. The strengthened Au-Pt-M alloy is conducive to promoting the further development and application of alloy materials in high-end medical devices.

[0096] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for improving the elastic properties of Au-Pt alloy, characterized in that: The following steps are involved: Establish a supercell model of the Au-Pt binary alloy and optimize the structure of the supercell model to obtain the optimized supercell model of the Au-Pt binary alloy with the lowest energy; Alloying atoms were introduced into the optimized supercell model of Au-Pt binary alloy to establish the Au-Pt-M alloy supercell model; The ground state energy of the Au-Pt-M alloy supercell model was calculated. Taking the lowest ground state energy as the criterion, the preferred position of the alloying atoms was determined to obtain the optimized supercell model of the Au-Pt-M alloy. The binding energy and elastic performance data of the optimized supercell model of Au-Pt-M alloy were obtained to screen out alloying elements with more significant improvement in elastic properties.

2. The method for improving the elastic properties of Au-Pt alloy according to claim 1, characterized in that: The method to establish the Au-Pt-M alloy supercell model is: The replacement atomic sites of the optimized supercell model of the Au-Pt binary alloy are obtained, and the alloying atoms are sequentially replaced with multiple replacement atomic sites, thereby introducing the alloying atoms into the optimized supercell model of the Au-Pt binary alloy to establish the Au-Pt-M alloy supercell model.

3. The method for improving the elastic properties of Au-Pt alloy according to claim 2, characterized in that: M represents an alloying atom; the alloying atom is Zr, Nb, Mo, Hf, Ta, W, Re, Cu, Pd, Ir, Zn, Y, Ru, Rh, Ag, Cd, La, Ce or Os.

4. The method for improving the elastic properties of Au-Pt alloy according to claim 1, characterized in that: The method for determining the preferred occupancy of alloying atoms is as follows: The ground state energy of the Au-Pt-M alloy supercell model was calculated to obtain the total ground state energy of the Au-Pt-M alloy supercell model at the corresponding substitutional atomic sites of different alloying atoms. Taking the lowest ground state energy as the standard, the substitutional atomic sites of Au atoms in which alloying atoms are more likely to occupy were determined as the preferential occupancy sites of alloying atoms, and the optimized supercell model of the Au-Pt-M alloy was established.

5. The method for improving the elastic properties of Au-Pt alloy according to claim 1, characterized in that: The method for obtaining the binding energy of the Au-Pt-M alloy optimized supercell model is as follows: According to the obtained Au-Pt-M alloy optimized supercell model, the total ground state energy of the Au-Pt-M alloy supercell model, the total number of Au, Pt and M atoms, and the sum of the ground state energies of Au, Pt and M atoms in the solid state are obtained; The binding energy of the optimized supercell model of the Au-Pt-M alloy is obtained by subtracting the sum of the ground state energies of Au, Pt, and M atoms in the solid state from the total ground state energy of the Au-Pt-M alloy supercell model and then dividing it by the total number of Au, Pt, and M atoms.

6. The method for improving the elastic properties of Au-Pt alloy according to claim 5, characterized in that: The calculation formula of the binding energy of the Au-Pt-M alloy optimized supercell model is as follows: Where ΔH represents the binding energy of the optimized supercell model of Au-Pt-M alloy; E tot represents the total ground state energy of the Au-Pt-M alloy supercell model; represents the ground state energy of a single Au atom in the solid state; represents the ground state energy of a single Pt atom in the solid state; represents the ground state energy of a single M atom in the solid state; N Au represents the number of Au atoms; H Pt represents the number of Pt atoms; N M represents the number of M atoms.

7. The method for improving the elastic properties of Au-Pt alloy according to claim 1, characterized in that: The method to obtain the elastic properties data of the optimized supercell model of Au-Pt-M alloy is: The elastic properties of the Au-Pt-M alloy optimized supercell model were calculated, and the elastic performance data of the Au-Pt-M alloy optimized supercell model with different alloying atoms were obtained.

8. The method for improving the elastic properties of Au-Pt alloy according to claim 7, characterized in that: The elastic properties include bulk modulus, shear modulus, Young's modulus, Poisson's ratio, B / G value and Vickers hardness value.

9. The method for improving the elastic properties of Au-Pt alloy according to claim 1, characterized in that: The method to select alloying elements that can improve elastic properties more significantly is: By comparing the binding energy and elastic constants of the optimized supercell model of Au-Pt-M alloy, alloying elements with relatively low binding energy and relatively high elastic constants are obtained.

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