Method for improving plasticity of ir-rh alloy and ir-rh alloy

Abstract

The patent application discloses a method for improving the plasticity of Ir-Rh alloy and an Ir-Rh alloy, and the method comprises the following steps: step 1, establishing an Ir-Rh binary alloy solid solution and an Ir-Rh-X ternary alloy solid solution model; step 2, based on the first principle calculation, performing high-precision structural relaxation on the solid solution model to obtain the static total energy and the lattice constant; step 3, based on the lattice constant of the solid solution model, calculating the Poisson's ratio, the stacking fault energy and the D parameters of the Ir-Rh binary alloy solid solution and the Ir-Rh-X ternary alloy solid solution, evaluating the plasticity, and screening potential alloy element types; and step 4, using a method for calculating a phase diagram to calculate the unstable stacking fault energy of the Ir-Rh-X ternary alloy to obtain the composition range of the Ir-Rh-X ternary alloy. By using the method, the plasticity of the Ir-Rh alloy is improved, the alloy cost is reduced, the alloy element is screened by using a high-throughput calculation method, the research and development cycle is greatly shortened, and the research and development cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of high-temperature alloy composition design technology, specifically to a method for improving the plasticity of Ir-Rh alloys and an Ir-Rh alloy. Background Technology

[0002] Iridium (Ir) possesses a high melting point and excellent corrosion resistance, making it widely used in high-temperature thermocouples and spark plug electrodes, facing harsh service environments characterized by high temperatures, oxidation, and corrosion. However, iridium primarily fails via intergranular fracture, exhibiting significant brittle fracture. To improve the plasticity of Ir, alloying methods are commonly employed, adding small amounts of alloying elements to form Ir-based multi-element alloys. Researchers such as Yamabe-Mitarai have found that tungsten can significantly enhance the plasticity of iridium, for example, in the Ir-0.3wt.%W alloy. Furthermore, doping with trace elements (such as thorium or cerium) can further improve the plasticity of Ir-0.3W alloys. For instance, Liu et al. developed the DOP-26 alloy (Ir-0.3W-0.006Th-0.005Al(wt.%)), which exhibits excellent mechanical properties and is widely used as a shell material for plutonium fuel pellets. However, the DOP-26 alloy forms ThO2 under low oxygen partial pressure conditions, leading to a decrease in its plasticity. To improve the plasticity of iridium while ensuring its oxidation resistance, rh, with its high melting point and excellent oxidation resistance, is typically chosen as a dopant element, such as Ir-10Rh, Ir-20Rh, and Ir-30Rh alloys. Ir-Rh alloy thermocouples can operate at temperatures up to 2373K and remain stable even in low-oxygen environments or in air. Although adding rh improves the plasticity of iridium, Ir-30Rh has a Poisson's ratio of approximately 0.25, and iridium-rhodium alloys still face problems such as insufficient plasticity and high cost. Therefore, how to quickly screen alloying elements, optimize alloy composition, further improve the plasticity of Ir-Rh alloys, and reduce their cost are urgent problems to be solved. Summary of the Invention

[0003] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a method for improving the plasticity of Ir-Rh alloys and an Ir-Rh alloy. The method of this invention improves the plasticity of Ir-Rh alloys while reducing alloy costs. The use of high-throughput calculation methods to screen alloying elements greatly shortens the research and development cycle and reduces research and development costs.

[0004] The technical solution adopted in this invention is as follows:

[0005] A method for improving the plasticity of Ir-Rh alloys includes the following steps:

[0006] Step 1: Using a special quasi-random approximation method, establish the crystal structure of the Ir-Rh binary alloy solid solution, including Ir 47 Rh1, Ir 44 Rh4, Ir 40 Rh8 and Ir 32 Rh 16 ; Ir 47 Replacing one Ir atom in the Rh1 supercell with an alloying element (X = Si, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, La, Ce, Hf, Ta, W, Re, Os, Ir, Au, Th) establishes the Ir... 46 A solid solution model of Rh1X1;

[0007] Step 2: Based on first-principles calculations, perform high-precision structural relaxation on the solid solution model to obtain the static total energy and lattice constant. Based on the static total energy, determine the role of alloying elements in Ir. 46 The specific location of Rh1X1 is used to determine the solid solution of alloying elements in Ir. 46 The final crystal structure, static total energy, and lattice constant of Rh1X1;

[0008] Step 3: Based on the lattice constant of the solid solution model, calculate the Poisson's ratio, stacking fault energy and D parameter of Ir-Rh binary alloy solid solution and Ir-Rh-X ternary alloy solid solution, evaluate their plasticity, and screen potential alloying elements.

[0009] Step 4: Calculate the unstable stacking fault energy of the Ir-Rh-X ternary alloy using the phase diagram calculation method, and obtain the composition range of the Ir-Rh-X ternary alloy.

[0010] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0011] 1. A systematic and comprehensive screening of all transition elements was conducted to identify alloy types that could simultaneously improve the plasticity of Ir-Rh alloys and reduce their cost. At the same time, the plasticity of the Ir-rich end of the Ir-Rh-X ternary alloy was evaluated using a phase diagram calculation method, and the alloy composition was further optimized.

[0012] 2. The addition of transition metals significantly reduces the amount of precious metals used, thereby improving the plasticity of Ir-Rh alloys while lowering alloy costs.

[0013] 3. High-throughput computational methods were used to screen alloying elements, which greatly shortened the research and development cycle and reduced research and development costs.

[0014] In a preferred embodiment of the present invention, step 1 includes:

[0015] Step 1.1 Obtain the crystal structure of Ir based on the Materials Project database. The space group is Fm-3m, the space group number is No. 225, and the unit cell contains 4 Ir atoms. Obtain the crystal structure of Rh based on the Materials Project database. The space group is Fm-3m, the space group number is No. 225, and the unit cell contains 4 Rh atoms.

[0016] Step 1.2 Perform vector transformation on the unit cell of Ir, so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the

[111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Ir). 48 ); Perform a vector transformation on the unit cell of Rh so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the

[111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Rh 48 );

[0017] Step 1.3 employs a special quasi-random approximation method to establish the crystal structure of the Ir-Rh binary alloy solid solution, including Ir 47 Rh1, Ir 44 Rh4, Ir 40 Rh8 and Ir 32 Rh 16 ;

[0018] Step 1.4 considers three nearest neighbor relationships between Rh atoms and alloying elements: the first nearest neighbor (P1(0.0250, 0.750, 0.500), P2(0.0500, 0.500, 0.500), P3(0.050, 0.000, 0.500), P4(0.166, 0.000, 0.666) and P5(0.4160, 0.0250, 0.666)), and the second nearest neighbor (P6(0.416, 0.0250, 0.666)). 0.750, 0.666), P7(0.0750, 0.0250, 0.500), P8(0.666, 0.000, 0.666), P9(0.333, 0.000, 0.833) and P10(0.833, 0.0250, 0.833)) and the third nearest neighbor (P11(0.0750, 0.0750, 0.500) and P12(0.583, 0.0250, 0.833))), will Ir 47Replacing one Ir atom in the Rh1 supercell with an alloying element (X = Si, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, La, Ce, Hf, Ta, W, Re, Os, Ir, Au, Th) establishes the Ir... 46 Solid solution model of Rh1X1.

[0019] This scheme uses a special quasi-random approximation method to simultaneously consider the different nearest neighbor positions of alloying elements, which can describe the true situation of disordered alloys to the greatest extent and make the calculation results consistent with reality.

[0020] In a preferred embodiment of the present invention, step 2 includes:

[0021] Step 2.1 Calculate based on first principles for Ir and Ir 47 Rh1、Ir 44 Rh4, Ir 40 Rh8, Ir 32 Rh 16 High-precision structural relaxation was performed with Rh, and the energy convergence criterion was set to 10. -6 eV / atom, the convergence criterion for force is The K-point grid is 6×10×2, and the static total energy and lattice constant are obtained.

[0022] Step 2.2 Calculates Ir based on first-principles calculations. 46 High-precision structural relaxation of Rh1X1 solid solution was performed, with an energy convergence criterion of 10. -6 eV / atom, the convergence criterion for force is The K-point grid is 3×5×1, and the static total energy and lattice constant are obtained.

[0023] Step 2.3 uses binding energy to evaluate the role of alloying elements in Ir 46 The optimal placeholder in Rh1X1 is shown below.

[0024] ΔE=E(Ir 46 Rh1X1)-E(Ir)-E(Rh)-E(X)1

[0025] Where E(Ir) 46 Rh1X1), E(Ir), E(Rh) and E(X) are respectively Ir 46 The energies of Rh1X1, Ir, Rh, and alloying elements are used to determine the alloying element's position in Ir. 46 The final solid solution model in Rh1X1.

[0026] This method uses high-precision structural relaxation to accurately obtain the ground state energy corresponding to each crystal structure, determine the preferred occupancy of alloying elements, and make the calculation results consistent with reality.

[0027] In a preferred embodiment of the present invention, step 3 includes:

[0028] Step 3.1 Calculate the Ir-Rh binary alloy solid solution and Ir using the stress-strain method. 46 The elastic constants of Rh1X1 solid solution include C 11 C 12 and C 44 The elastic modulus is calculated using the Voigt-Reuss-Hill law, as shown below:

[0029]

[0030] G V =(C 11 -C 12 +3C 44 ) / 5 3

[0031] G R =5(C 11 -C 12 C 44 / [4C 44 +3(C 11 -C 12 )] 4

[0032] G = (G V +G R ) / 2 5

[0033]

[0034]

[0035] Among them G V G R G and B are the shear moduli calculated using Voigt's law, Reuss's law, and Hill's law, respectively. V B R B and B are the shear moduli calculated using Voigt's law, Reuss's law and Hill's law, respectively, and υ is Poisson's ratio;

[0036] Step 3.2 Calculate the Ir-Rh binary alloy solid solution and Ir 46 Rh1X1 solid solution in <111> Stacking fault energy curves with surface slippage along the [11-2] direction.

[0037]

[0038] Where E0 and Eb are the energies of a perfect unit cell and a unit cell with stacking faults, respectively. A is the stacking fault area, and γ is the stacking fault.

[0039] Step 3.3 further evaluates the Ir-Rh binary alloy solid solution and Ir using the Rice standard. 46 The plasticity of Rh1X1 solid solution is shown below.

[0040]

[0041] Where γ SUR and γ USFE These represent surface energy and unstable stacking fault energy, respectively. D is the Rice standard, and a high D value indicates better plasticity.

[0042] Step 3.4 simultaneously considers Poisson's ratio, unstable stacking fault energy, and D value to screen for effective alloying elements.

[0043] This method considers both Poisson's ratio and Rice standard to determine the effect of alloying elements on the plasticity of Ir-Rh alloys, thus improving accuracy.

[0044] In a preferred embodiment of the present invention, step 4 includes:

[0045] Step 4.1 uses the phase diagram calculation method to calculate the stacking fault energy of the Ir-Rh-X ternary alloy and optimize the concentration of alloying elements, as shown below.

[0046] γ Ir-Rh-X =x Ir *γ Ir +x Rh *γ Rh +x X *γ X +x Ir x Rh * 0 L Ir-Rh +x Ir x X * 0 L Ir-X 2

[0047] Where x Ir x Rh and x X These represent the atomic fractions of Ir, Rh, and other alloying elements in the Ir-Rh-X ternary alloy, respectively, and γ. Ir γ Rh and γ X The stacking fault energies of Ir, Rh, and alloying elements are respectively. 0 L Ir-Rh and 0 LIr-X These are the interaction parameters between Ir and Rh and the interaction parameters between Ir and alloying elements, respectively.

[0048] Step 4.2 Using the unstable stacking fault energy of Ir-30Rh as a reference, obtain the composition range of the ternary alloy.

[0049] This scheme uses the stacking fault energy of a fixed composition combined with the calculation of phase diagrams to extrapolate the stacking fault energy of different compositions, thereby rapidly optimizing the alloy composition.

[0050] An Ir-Rh alloy prepared by any of the methods described above for improving the plasticity of an Ir-Rh alloy.

[0051] As a preferred embodiment of the present invention, the Ir-Rh alloy is an Ir-Rh-Cu alloy with a composition range of 21.5-30.0 at.% Rh, 0.3-3.0 at.% Cu, and Ir as the balance.

[0052] As a preferred embodiment of the present invention, the Ir-Rh alloy is an Ir-Rh-Zn alloy (composition range: 23.3-30.0 at.% Rh, 0.4-3.0 at.% Zn, with Ir as the balance).

[0053] As a preferred embodiment of the present invention, the Ir-Rh alloy is an Ir-Rh-Cd alloy with a composition range of 16.5-30.0 at.% Rh, 0.1-3.0 at.% Cd, and Ir as the balance.

[0054] As a preferred embodiment of the present invention, the Ir-Rh alloy is an Ir-Rh-Hf alloy with a composition range of 25.2-30.0 at.% Rh, 0.1-3.0 at.% Hf, and Ir as the balance. Attached Figure Description

[0055] Appendix Figure 1 This is a flowchart of a method for improving the plasticity of Ir-Rh alloys according to the present invention;

[0056] Appendix Figure 2 Crystal structure diagram of Ir-Rh binary alloy solid solution;

[0057] Appendix Figure 3 The diagram shows the stacking fault energy, Poisson's ratio, and D-parameter of the Ir-Rh binary alloy.

[0058] Appendix Figure 4 For Ir 46 Rh1X1 crystal structure diagram;

[0059] Appendix Figure 5 For alloying elements in Ir 46 Binding energy diagrams of different occupancy sites in Rh1X1;

[0060] Appendix Figure 6 For Ir 46 Poisson's ratio plot of Rh1X1;

[0061] Appendix Figure 7 For Ir 46 Unstable stacking fault energy and stable stacking fault energy diagram of Rh1X1;

[0062] Appendix Figure 8 For Ir 46 A graph of Poisson's ratio and D parameter for Rh1X1;

[0063] Appendix Figure 9 The diagram shows the unstable stacking fault energy and stable stacking fault energy of the Ir-Rh-X ternary alloy. Detailed Implementation

[0064] Typical embodiments embodying the features and advantages of the present invention will be specifically described in the following description. It should be understood that the present invention can have various variations in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations herein are for illustrative purposes only and not intended to limit the present invention.

[0065] The following embodiments disclose a method for improving the plasticity of Ir-Rh alloys, as shown in the appendix. Figure 1 As shown, it includes the following steps:

[0066] Step 1: Establish solid solution models of Ir-Rh binary alloy and Ir-Rh-X ternary alloy.

[0067] Step 1.1 Obtain the crystal structures of Ir and Rh based on the Materials Project database;

[0068] Step 1.2 Perform vector transformation on the unit cell of Ir, so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the

[111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Ir). 48 ); Perform a vector transformation on the unit cell of Rh so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the

[111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Rh 48 );

[0069] Step 1.3 employs a special quasi-random approximation method to establish the crystal structure of the Ir-Rh binary alloy solid solution, including Ir 47 Rh1, Ir 44 Rh4, Ir 40 Rh8 and Ir32 Rh 16 ;

[0070] Step 1.4 considers three nearest neighbor relationships between Rh atoms and alloying elements: the first nearest neighbor (P1(0.0250, 0.750, 0.500), P2(0.0500, 0.500, 0.500), P3(0.050, 0.000, 0.500), P4(0.166, 0.000, 0.666) and P5(0.4160, 0.0250, 0.666)), and the second nearest neighbor (P6(0.416, 0.0250, 0.666)). 0.750, 0.666), P7(0.0750, 0.0250, 0.500), P8(0.666, 0.000, 0.666), P9(0.333, 0.000, 0.833) and P10(0.833, 0.0250, 0.833)) and the third nearest neighbor (P11(0.0750, 0.0750, 0.500) and P12(0.583, 0.0250, 0.833))), will Ir 47 Replacing one Ir atom in the Rh1 supercell with an alloying element (X = Si, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, La, Ce, Hf, Ta, W, Re, Os, Ir, Au, Th) establishes the Ir... 46 Solid solution model of Rh1X1.

[0071] Step 2: High-precision structural relaxation to obtain lattice constants

[0072] Step 2.1 Calculate based on first principles for Ir and Ir 47 Rh1、Ir 44 Rh4, Ir 40 Rh8, Ir 32 Rh 16 High-precision structural relaxation was performed with Rh, and the energy convergence criterion was set to 10. -6 eV / atom, the convergence criterion for force is The K-point grid is 6×10×2. The static total energy and lattice constant are obtained as shown in Table 1.

[0073] Step 2.2 Calculates Ir based on first-principles calculations. 46 High-precision structural relaxation of Rh1X1 solid solution was performed, with an energy convergence criterion of 10. -6 eV / atom, the convergence criterion for force is The K-point grid is 3×5×1. The static total energy and lattice constant are obtained as shown in Table 1.

[0074] Table 1 Crystal structure information of Ir-Rh binary alloy solid solutions

[0075]

[0076] Step 2.3 Based on the static total energy, calculate Ir according to the following formula. 46 The binding energy of Rh1X1 determines the alloying element in Ir 46 The most stable placeholders in Rh1X1 are shown in Table 2.

[0077] ΔE=E(Ir 46 Rh1X1)-E(Ir)-E(Rh)-E(X)1

[0078] Where E(Ir) 46 Rh1X1), E(Ir), E(Rh) and E(X) are respectively Ir 46 The energies of Rh1X1, Ir, Rh, and alloying elements are used to determine the alloying element's position in Ir. 46 The final solid solution model in Rh1X1.

[0079] Table 2 Ir 46 Binding energy and most stable site of Rh1X1

[0080]

[0081]

[0082] Step 3: Evaluate the plasticity of Ir-Rh binary alloy solid solutions and Ir-Rh-X ternary alloy solid solutions

[0083] Step 3.1 Calculate the Ir-Rh binary alloy solid solution and Ir using the stress-strain method. 46 The elastic constants of Rh1X1 solid solution include C 11 C 12 and C 44 The elastic modulus is calculated using the Voigt-Reuss-Hill law, as shown below:

[0084]

[0085] G V =(C 11 -C 12 +3C 44 ) / 5 3

[0086] G R =5(C 11 -C 12 C 44 / [4C 44 +3(C 11 -C12 )] 4

[0087] G = (G V +G R ) / 2 5

[0088]

[0089]

[0090] Among them G V G R G and B are the shear moduli calculated using Voigt's law, Reuss's law, and Hill's law, respectively. V B R B and B are the shear moduli calculated using Voigt's law, Reuss's law and Hill's law, respectively, and υ is Poisson's ratio;

[0091] Step 3.2 Calculate the Ir-Rh binary alloy solid solution and Ir 46 Rh1X1 solid solution in <111> Stacking fault energy curves with surface slippage along the [11-2] direction.

[0092]

[0093] Where E0 and Eb are the energies of a perfect unit cell and a unit cell with stacking faults, respectively. A is the stacking fault area, and γ is the stacking fault.

[0094] Step 3.3 further evaluates the Ir-Rh binary alloy solid solution and Ir using the Rice standard. 46 The plasticity of Rh1X1 solid solution is shown below.

[0095]

[0096] Where γ SUR and γ USFE These represent surface energy and unstable stacking fault energy, respectively. D is the Rice standard, and a high D value indicates better plasticity.

[0097] Step 3.4 simultaneously considers Poisson's ratio, unstable stacking fault energy, and D value to screen for effective alloying elements.

[0098] Step 4: Composition optimization of Ir-Rh-X ternary alloy

[0099] Step 4.1 uses the phase diagram calculation method to calculate the stacking fault energy of the Ir-Rh-X ternary alloy and optimize the concentration of alloying elements, as shown below.

[0100] γ Ir-Rh-X =x Ir *γ Ir+x Rh *γ Rh +x X *γ X +x Ir x Rh * 0 L Ir-Rh +x Ir x X * 0 L Ir-X 10

[0101] Where x Ir x Rh and x X These represent the atomic fractions of Ir, Rh, and other alloying elements in the Ir-Rh-X ternary alloy, respectively, and γ. Ir γ Rh and γ X The stacking fault energies of Ir, Rh, and alloying elements are respectively. 0 L Ir-Rh and 0 L Ir-X These are the interaction parameters between Ir and Rh and the interaction parameters between Ir and alloying elements, respectively.

[0102] Step 4.2 Using the unstable stacking fault energy of Ir-30Rh as a reference, obtain the composition range of the ternary alloy.

[0103] The following examples, Ir-Rh binary alloy and Ir-Rh-X (X = Cu, Zn, Cd and Hf) ternary alloy, are used to illustrate the specific steps of the present invention in detail. The method for screening other effective alloying elements is the same.

[0104] Example 1

[0105] This embodiment discloses an Ir-Rh-Cu ternary alloy and its preparation method, as detailed below:

[0106] Step 1: Establish a solid solution model of the Ir-Rh-Cu ternary alloy.

[0107] Step 1.1 Obtain the unit cell crystal structures of Ir and Rh based on the Materials Project database;

[0108] Step 1.2 Perform vector transformation on the unit cell of Ir, so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the

[111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Ir). 48); Perform a vector transformation on the unit cell of Rh so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the

[111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Rh 48 );

[0109] Step 1.3 will Ir 48 Replace one Ir atom in the supercell with an Rh atom to establish Ir 47 Rh1 solid solution model, Ir 47 Replacing one Ir atom with Cu in the Rh1 supercell establishes an Ir... 46 The solid solution model of Rh1Cu1, such as Figure 4 As shown.

[0110] Step 2: High-precision structural relaxation to obtain lattice constants

[0111] Step 2.1 Calculate based on first principles for Ir 46 Rh1Cu1 is subjected to high-precision structural relaxation, with the energy convergence criterion set to 10. -6 eV / atom, the convergence criterion for force is The K-point grid is 3×5×1, and the static total energy and lattice constant are obtained.

[0112] Step 2.3 uses binding energy to evaluate the role of alloying elements in Ir 46 The optimal occupancy in Rh1Cu1, such as Figure 5 As shown, Cu tends to occupy the P1 site, and Ir 46 The binding energy of Rh1Cu1 is -17.7896 eV / atom, which determines the alloying elements in Ir. 46 The final solid solution model in Rh1Cu1.

[0113] Step 3: Evaluate Ir 46 Plasticity of Rh1Cu1 solid solution

[0114] Step 3.1 Calculate the elastic modulus Ir using the stress-strain method combined with the Voigt-Reuss-Hill law. 46 The bulk modulus, shear modulus, and Young's modulus of the Rh1Cu1 solid solution are 452.21 GPa, 261.37 GPa, and 657.69 GPa, respectively. Ir 46 The Poisson's ratio of the Rh1Cu1 solid solution is 0.258, such as Figure 6 As shown, Cu can significantly increase Ir's Poisson's ratio and improve its plasticity;

[0115] Step 3.2 Calculate Ir 46 Rh1Cu1 solid solution in <111> Stacking fault energy curves of surface slip along the [11-2] direction, Ir46 The unstable stacking fault energy of Rh1Cu1 solid solution is 672.21 mJ / m. 2 ,like Figure 7 As shown, Cu can significantly reduce the unstable stacking fault energy of Ir and improve its plasticity;

[0116] Step 3.3 further evaluates the plasticity of the alloy using the Rice standard, Ir 46 The D value of the Rh1Cu1 solid solution is 4.07, such as Figure 8 As shown, Cu can significantly increase the D value of Ir and improve its plasticity;

[0117] Step 3.4 Comprehensive consideration of Ir 46 The Poisson's ratio, unstable stacking fault energy, and D value of the Rh1Cu1 solid solution indicate that Cu is beneficial for improving the plasticity of Ir.

[0118] Step 4: Composition optimization of the Ir-Rh-Cu ternary alloy

[0119] Step 4.1 uses the phase diagram calculation method to calculate the stacking fault energy of the Ir-Rh-Cu ternary alloy and optimize the concentration of alloying elements. γ Ir γ Rh and γ Cu They are 766.05 mJ / m 2 744mJ / m 2 and 705mJ / m 2 . 0 L Ir-Rh and 0 L Ir-Cu The stacking fault energies are -819.48 and -2276.64, respectively. The stacking fault energies of the Ir-Rh-Cu ternary alloy are as follows: Figure 9 As shown;

[0120] Step 4.2 uses the unstable stacking fault energy of Ir-30Rh as a reference. Figure 9 The alloy composition range is divided into two regions. The alloy composition in region 1 can significantly reduce the unstable stacking fault energy and stable stacking fault energy of the alloy. The composition range of the Ir-Rh-Cu alloy is: 21.5-30.0 at.% Rh, 0.3-3.0 at.% Cu, with Ir as the balance.

[0121] Example 2

[0122] This embodiment discloses an Ir-Rh-Zn ternary alloy and its preparation method, as detailed below:

[0123] Step 1: Establish a solid solution model of the Ir-Rh-Zn ternary alloy.

[0124] Step 1.1 Obtain the unit cell crystal structures of Ir and Rh based on the Materials Project database;

[0125] Step 1.2 Perform vector transformation on the unit cell of Ir, so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the

[111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Ir). 48 );

[0126] Step 1.3 will Ir 48 Replace one Ir atom in the supercell with an Rh atom to establish Ir 47 Rh1 solid solution model; Ir 47 In the Rh1 supercell, one Ir atom is replaced with Zn to establish Ir 46 The solid solution model of Rh1Zn1, such as Figure 4 As shown.

[0127] Step 2: High-precision structural relaxation to obtain lattice constants

[0128] Step 2.1 Calculate based on first principles for Ir 46 Rh1Zn1 is subjected to high-precision structural relaxation, with the energy convergence criterion set to 10. -6 eV / atom, the convergence criterion for force is The K-point grid is 3×5×1, and the static total energy and lattice constant are obtained.

[0129] Step 2.2 Use binding energy to evaluate the role of alloying elements in Ir 46 The optimal placeholder in Rh1Zn1, such as Figure 5 As shown, Zn tends to occupy position P1, and Ir 46 The binding energy of Rh1Zn1 is -17.8652 eV / atom, which determines the alloying elements in Ir. 46 The final solid solution model in Rh1Zn1.

[0130] Step 3: Evaluate Ir 46 Plasticity of Rh1Zn1 solid solution

[0131] Step 3.1 Calculate the elastic modulus Ir using the stress-strain method combined with the Voigt-Reuss-Hill law. 46 The bulk modulus, shear modulus, and Young's modulus of the Rh1Zn1 solid solution are 454.39 GPa, 263.54 GPa, and 661.75 GPa, respectively. Ir 46 The Poisson's ratio of the Rh1Zn1 solid solution is 0.257, such as Figure 6 As shown, Zn can significantly increase the Poisson's ratio of Ir and improve its plasticity;

[0132] Step 3.2 Calculate Ir 46 Rh1Zn1 solid solution in <111> Stacking fault energy curves of surface slip along the [11-2] direction, Ir 46 The unstable stacking fault energy of the Rh1Zn1 solid solution is 694 mJ / m. 2 ,like Figure 7 As shown, Zn can significantly reduce the unstable stacking fault energy of Ir and improve its plasticity;

[0133] Step 3.3 further evaluates the plasticity of the alloy using the Rice standard, Ir 46 The D value of the Rh1Zn1 solid solution is 3.94, such as Figure 8 As shown, Zn can significantly increase the D value of Ir and improve its plasticity;

[0134] Step 3.4 Comprehensive consideration of Ir 46 The Poisson's ratio, unstable stacking fault energy, and D value of Rh1Zn1 solid solution indicate that Zn element is beneficial to improving the plasticity of Ir.

[0135] Step 4: Composition optimization of the Ir-Rh-Zn ternary alloy

[0136] Step 4.1 uses the phase diagram calculation method to calculate the stacking fault energy of the Ir-Rh-Zn ternary alloy and optimize the concentration of alloying elements. γ Ir γ Rh and γ Zn They are 766.05 mJ / m 2 744mJ / m 2 and 718mJ / m 2 . 0 L Ir-Rh and 0 L Ir-Zn The stacking fault energies are -819.48 and -1464.79, respectively. The stacking fault energies of the Ir-Rh-Zn ternary alloy are as follows: Figure 9 As shown;

[0137] Step 4.2 uses the unstable stacking fault energy of Ir-30Rh as a reference. Figure 9 The alloy composition range is divided into two regions. The alloy composition in region 1 can significantly reduce the unstable stacking fault energy and stable stacking fault energy of the alloy. The composition range of the Ir-Rh-Zn alloy is: 23.3-30.0 at.% Rh, 0.4-3.0 at.% Zn, with Ir as the balance.

[0138] Example 3

[0139] This embodiment discloses an Ir-Rh-Cd ternary alloy and its preparation method, as detailed below:

[0140] Step 1: Establish a solid solution model of the Ir-Rh-Cd ternary alloy.

[0141] Step 1.1 Obtain the unit cell crystal structures of Ir and Rh based on the Materials Project database;

[0142] Step 1.2 Perform vector transformation on the unit cell of Ir, so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the

[111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Ir). 48 );

[0143] Step 1.3 will Ir 48 Replace one Ir atom in the supercell with an Rh atom to establish Ir 47 Rh1 solid solution model. Ir 47 In the Rh1 supercell, one Ir atom is replaced with Cd to establish Ir 46 The solid solution model of Rh1Cd1, such as Figure 4 As shown.

[0144] Step 2: High-precision structural relaxation to obtain lattice constants

[0145] Step 2.1 Calculate based on first principles for Ir 46 Rh1Cd1 is subjected to high-precision structural relaxation, with the energy convergence criterion set to 10. -6 eV / atom, the convergence criterion for force is The K-point grid is 3×5×1, and the static total energy and lattice constant are obtained.

[0146] Step 2.2 Use binding energy to evaluate the role of alloying elements in Ir 46 Optimal placeholder in Rh1Cd1, such as Figure 5 As shown, Cd tends to occupy position P1, and Ir 46 The binding energy of Rh1Cd1 is -17.5836 eV / atom, which determines the alloying elements in Ir. 46 The final solid solution model in Rh1Cd1.

[0147] Step 3: Evaluate Ir 46 Plasticity of Rh1Cd1 solid solution

[0148] Step 3.1 Calculate the elastic modulus Ir using the stress-strain method combined with the Voigt-Reuss-Hill law. 46 The bulk modulus, shear modulus, and Young's modulus of the Rh1Cd1 solid solution are 458.91 GPa, 269.85 GPa, and 675.94 GPa, respectively. Ir 46The Poisson's ratio of the Rh1Cd1 solid solution is 0.254, such as Figure 6 As shown, Cd can significantly increase the Poisson's ratio of Ir, thereby improving its plasticity;

[0149] Step 3.2 Calculate Ir 46 Rh1Cd1 solid solution in <111> Stacking fault energy curves of surface slip along the [11-2] direction, Ir 46 The unstable stacking fault energy of Rh1Cd1 solid solution is 655.21 mJ / m. 2 ,like Figure 7 As shown, Cd can significantly reduce the unstable stacking fault energy of Ir and improve its plasticity;

[0150] Step 3.3 further evaluates the plasticity of the alloy using the Rice standard, Ir 46 The D value of the Rh1Cd1 solid solution is 4.06, such as Figure 8 As shown, Cd can significantly increase the D value of Ir and improve its plasticity;

[0151] Step 3.4 Comprehensive consideration of Ir 46 The Poisson's ratio, unstable stacking fault energy, and D value of Rh1Cd1 solid solution are all positively correlated with the plasticity of Ir.

[0152] Step 4: Composition optimization of the Ir-Rh-Cd ternary alloy

[0153] Step 4.1 uses the phase diagram calculation method to calculate the stacking fault energy of the Ir-Rh-Cd ternary alloy and optimize the concentration of alloying elements. γ Ir γ Rh and γ Cd They are 766.05 mJ / m 2 744mJ / m 2 and 683.32mJ / m 2 . 0 L Ir-Rh and 0 L Ir-Cd The stacking fault energies are -819.48 and -3357.06, respectively. The stacking fault energies of the Ir-Rh-Cd ternary alloy are as follows: Figure 9 As shown;

[0154] Step 4.2 uses the unstable stacking fault energy of Ir-30Rh as a reference. Figure 9 The alloy composition range is divided into two regions. The alloy composition in region 1 can significantly reduce the unstable stacking fault energy and stable stacking fault energy of the alloy. The composition range of the Ir-Rh-Cd alloy is: 16.5-30.0 at.% Rh, 0.1-3.0 at.% Cd, with Ir as the balance.

[0155] Example 4

[0156] This embodiment discloses an Ir-Rh-Hf ternary alloy and its preparation method, as detailed below:

[0157] Step 1: Establish a solid solution model of the Ir-Rh-Hf ternary alloy.

[0158] Step 1.1 Obtain the unit cell crystal structures of Ir and Rh based on the Materials Project database;

[0159] Step 1.2 Perform vector transformation on the unit cell of Ir, so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the

[111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Ir). 48 );

[0160] Step 1.3 will Ir 48 Replace one Ir atom in the supercell with an Rh atom to establish Ir 47 Rh1 solid solution model. Ir 47 In the Rh1 supercell, one Ir atom is replaced with Hf to establish Ir... 46 The solid solution model of Rh1Hf1, such as Figure 4 As shown.

[0161] Step 2: High-precision structural relaxation to obtain lattice constants

[0162] Step 2.1 Calculate based on first principles for Ir 46 Rh1Hf1 performs high-precision structural relaxation, setting the energy convergence criterion to 10. -6 eV / atom, the convergence criterion for force is The K-point grid is 3×5×1, and the static total energy and lattice constant are obtained.

[0163] Step 2.2 Use binding energy to evaluate the role of alloying elements in Ir 46 The optimal placeholder in Rh1Hf1, such as Figure 5 As shown, Hf tends to occupy the P11 position, and Ir 46 The binding energy of Rh1Hf1 is -17.2634 eV / atom, which determines the alloying elements in Ir. 46 The final solid solution model in Rh1Hf1.

[0164] Step 3: Evaluate Ir 46 Plasticity of Rh1Hf1 solid solution

[0165] Step 3.1 Calculate the elastic modulus Ir using the stress-strain method combined with the Voigt-Reuss-Hill law. 46The bulk modulus, shear modulus, and Young's modulus of the Rh1Hf1 solid solution are 465.92 GPa, 272.85 GPa, and 683.91 GPa, respectively. Ir 46 The Poisson's ratio of the Rh1Hf1 solid solution is 0.255, such as Figure 6 As shown, Hf can significantly increase the Poisson's ratio of Ir, thereby improving its plasticity;

[0166] Step 3.2 Calculate Ir 46 Rh1Hf1 solid solution in <111> Stacking fault energy curves of surface slip along the [11-2] direction, Ir 46 The unstable stacking fault energy of the Rh1Hf1 solid solution is 704.79 mJ / m. 2 ,like Figure 7 As shown, Hf can significantly reduce the unstable stacking fault energy of Ir and improve its plasticity;

[0167] Step 3.3 further evaluates the plasticity of the alloy using the Rice standard, Ir 46 The D value of the Rh1Hf1 solid solution is 3.75, such as Figure 8 As shown, Hf element can significantly increase the D value of Ir and improve plasticity;

[0168] Step 3.4 Comprehensive consideration of Ir 46 The Poisson's ratio, unstable stacking fault energy, and D value of Rh1Hf1 solid solution are all positively correlated with the presence of Hf, which is beneficial for improving the plasticity of Ir.

[0169] Step 4: Composition optimization of the Ir-Rh-Hf ternary alloy

[0170] Step 4.1 uses the phase diagram calculation method to calculate the stacking fault energy of the Ir-Rh-Hf ternary alloy and optimize the concentration of alloying elements. γ Ir γ Rh and γ Hf They are 766.05 mJ / m 2 744mJ / m 2 and 728mJ / m 2 . 0 L Ir-Rh and 0 L Ir-Hf The stacking fault energies are -819.48 and -927.26, respectively. The stacking fault energies of the Ir-Rh-Hf ternary alloy are as follows: Figure 9 As shown;

[0171] Step 4.2 uses the unstable stacking fault energy of Ir-30Rh as a reference. Figure 9The alloy composition range is divided into two regions. The alloy composition in region 1 can significantly reduce the unstable stacking fault energy and stable stacking fault energy of the alloy. The composition range of the Ir-Rh-Hf alloy is: 25.2-30.0 at.% Rh, 0.1-3.0 at.% Hf, with Ir as the balance.

[0172] Comparative Example 1

[0173] This comparative example is an Ir-Rh binary alloy and its preparation method, as detailed below:

[0174] Step 1: Establish an Ir-Rh binary alloy solid solution model

[0175] Step 1.1 Obtain the unit cell crystal structures of Ir and Rh based on the Materials Project database;

[0176] Step 1.2 Perform vector transformation on the unit cell of Ir, so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the

[111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Ir). 48 ); Perform a vector transformation on the unit cell of Rh so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the

[111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Rh 48 );

[0177] Step 1.3 Based on Ir 48 The supercell crystal structure model is established using a special quasi-random approximation method to establish Ir 47 Rh1、Ir 44 Rh4, Ir 40 Rh8 and Ir 32 Rh 16 The crystal structure model is shown in the attached figure. Figure 2 As shown.

[0178] Step 2: High-precision structural relaxation to obtain lattice constants

[0179] Step 2.1 Based on first-principles calculations, the six crystal structures obtained in Step 1, including Ir, Ir 47 Rh1、Ir 44 Rh4, Ir 40 Rh8, Ir 32 Rh 16 High-precision structural relaxation was performed using Rh, with the energy convergence criterion set to 10. -6 eV / atom, the convergence criterion for force is The K-point grid is 6×10×2. The static total energy and lattice constant are obtained. Ir, Ir 47 Rh1、Ir 44 Rh4, Ir 40 Rh8, Ir 32 Rh 16 The lattice constants of Rh are respectively and

[0180] Step 3: Evaluate the plasticity of the Ir-Rh binary alloy solid solution.

[0181] Step 3.1 Calculate the elastic modulus Ir and Ir using the stress-strain method combined with the Voigt-Reuss-Hill law. 47 Rh1、Ir 44 Rh4, Ir 40 Rh8, Ir 32 Rh 16 The bulk moduli of Ir and Rh were 391.79 GPa, 380.59 GPa, 377.46 GPa, 373.59 GPa, 350.50 GPa, and 277.45 GPa, respectively. 47 Rh1、Ir 44 Rh4, Ir 40 Rh8, Ir 32 Rh 16 The shear moduli of Ir and Rh are 262.03 GPa, 240.61 GPa, 232.90 GPa, 226.46 GPa, 212.33 GPa, and 158.22 GPa, respectively. 47 Rh1、Ir 44 Rh4, Ir 40 Rh8, Ir 32 Rh 16 The Young's moduli of Ir and Rh are 642.80 GPa, 596.20 GPa, 579.52 GPa, 565.19 GPa, 529.98 GPa, and 398.86 GPa, respectively. 47 Rh1、Ir 44 Rh4, Ir 40 Rh8, Ir 32 Rh 16 Poisson with Rh, for example Figure 3 As shown, the values ​​are 0.226, 0.238, 0.244, 0.247, 0.248, and 0.260, respectively. To improve the plasticity of the Ir-Rh alloy, the Rh content must be increased, which is expensive.

[0182] Step 3.2 Calculation of Ir-Rh binary alloy in <111> Stacking fault energy curves of surface slip along the [11-2] direction, Ir, Ir47 Rh1、Ir 44 Rh4, Ir 40 Rh8, Ir 32 Rh 16 The unstable stacking fault energy of Rh is as follows Figure 3 As shown, they are 766.05 mJ / m 2 762.2mJ / m 2 753.95mJ / m 2 720.07mJ / m 2 714.09mJ / m 2 and 510.06mJ / m 2 As the Rh content increases, the unstable stacking fault energy of the Ir-Rh binary alloy gradually decreases, the slip barrier decreases, which is conducive to slip.

[0183] Step 3.3 further evaluates the plasticity of the alloy using the Rice standard, Ir, Ir 47 Rh1、Ir 44 Rh4, Ir 40 Rh8, Ir 32 Rh 16 The unstable stacking fault energy of Rh is as follows Figure 3 As shown, the values ​​are 3.74, 3.75, 3.77, 3.80, 3.88, and 4.41, respectively, indicating that to achieve better plasticity, the Rh content needs to be increased.

[0184] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A method for improving the plasticity of Ir-Rh alloys, characterized in that, Includes the following steps: Step 1: Using a special quasi-random approximation method, establish the crystal structure of the Ir-Rh binary alloy solid solution, including Ir 47 Rh1, Ir 44 Rh4, Ir 40 Rh8 and Ir 32 Rh 16 Replace one Ir atom in the Ir47Rh1 supercell with each of the alloying elements X, including Si, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, La, Ce, Hf, Ta, W, Re, Os, Ir, Au, and Th to establish the Ir... 46 A solid solution model of Rh1X1; Step 2: Based on first-principles calculations, perform high-precision structural relaxation on the solid solution model to obtain the static total energy and lattice constant. Based on the static total energy, determine the role of alloying elements in Ir. 46 The specific location of Rh1X1 is used to determine the solid solution of alloying elements in Ir. 46 The final crystal structure, static total energy, and lattice constant of Rh1X1; Step 3: Based on the lattice constant of the solid solution model, calculate the Poisson's ratio, stacking fault energy and D parameter of Ir-Rh binary alloy solid solution and Ir-Rh-X ternary alloy solid solution, evaluate their plasticity, and screen potential alloying elements. Step 4: Calculate the unstable stacking fault energy of the Ir-Rh-X ternary alloy using the phase diagram calculation method, and obtain the composition range of the Ir-Rh-X ternary alloy.

2. The method for improving the plasticity of Ir-Rh alloy according to claim 1, characterized in that: Step 1 includes: Step 1.1 Obtain the crystal structures of Ir and Rh based on the Materials Project database; Step 1.2 Perform vector transformation on the unit cell of Ir so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the [111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Ir). 48 ); Perform a vector transformation on the unit cell of Rh so that its x-axis is in the [11-2] direction of the unit cell, its y-axis is in the [1-10] direction of the unit cell, and its z-axis is in the [111] direction of the unit cell. At the same time, expand the unit cell obtained by the vector transformation into a 2×2×2 supercell (Rh 48 ); Step 1.3 Using a special quasi-random approximation method, the crystal structure of the Ir-Rh binary alloy solid solution is established, including Ir 47 Rh1, Ir 44 Rh4, Ir 40 Rh8 and Ir 32 Rh 16 ; Step 1.4 Consider the three nearest neighbor relationships between Rh atoms and alloying elements: the first nearest neighbor (P1(0.0250, 0.750, 0.500), P2(0.0500, 0.500, 0.500), P3(0.050, 0.000, 0.500), P4(0.166, 0.000, 0.666) and P5(0.4160, 0.0250, 0.666)), the second nearest neighbor (P6(0.416, 0.07...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)...)*)...)*)...) )*) )*) ) ) ) ) ) ) "*) ") ) "" ) "*) 0.—" 0.""'" 0."" "" " """" ")`" " """""""" " ... 50, 0.666), P7 (0.0750, 0.0250, 0.500), P8 (0.666, 0.000, 0.666), P9 (0.333, 0.000, 0.833) and P10 (0.833, 0.0250, 0.833)) and the third nearest neighbor (P11 (0.0750, 0.0750, 0.500) and P12 (0.583, 0.0250, 0.833)), will Ir 47 Replacing one Ir atom in the Rh1 supercell with an alloying element (X = Si, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, La, Ce, Hf, Ta, W, Re, Os, Ir, Au, Th) establishes Ir 46 Solid solution model of Rh1X1.

3. The method for improving the plasticity of Ir-Rh alloy according to claim 2, characterized in that: Step 2 includes: Step 2.1 Calculate Ir and Ir based on first-principles calculations. 47 Rh1、Ir 44 Rh4, Ir 40 Rh8, Ir 32 Rh 16 High-precision structural relaxation was performed with Rh, and the energy convergence criterion was set to 10. -6 eV / atom, the convergence criterion for the force is -10 eV / atom. -2 eV / Å, K-point grid is 6×10×2, obtain the static total energy and lattice constant; Step 2.2 Based on first-principles calculations, calculate for Ir 46 High-precision structural relaxation of Rh1X1 solid solution was performed, with an energy convergence criterion of 10. -6 eV / atom, the convergence criterion for the force is -10 eV / atom. -2 eV / Å, K-point grid is 3×5×1, obtain the static total energy and lattice constant; Step 2.3 Use binding energy to evaluate the role of alloying elements in Ir 46 The optimal placeholder in Rh1X1 is shown below. 1 Where E(Ir) 46 Rh1X1), E(Ir), E(Rh) and E(X) are respectively Ir 46 The energies of Rh1X1, Ir, Rh, and alloying elements are used to determine the alloying element's position in Ir. 46 The final solid solution model in Rh1X1.

4. The method for improving the plasticity of Ir-Rh alloy according to claim 3, characterized in that: Step 3 includes: Step 3.1 Calculate the Ir-Rh binary alloy solid solution and Ir using the stress-strain method. 46 The elastic constants of Rh1X1 solid solution include C 11 C 12 and C 44 The elastic modulus is calculated using the Voigt-Reuss-Hill law, as shown below: 2 3 4 5 6 7 Among them G V G R G and B are the shear moduli calculated using Voigt's law, Reuss's law, and Hill's law, respectively. V B R B and B are the shear moduli calculated using Voigt's law, Reuss's law and Hill's law, respectively, and υ is Poisson's ratio; Step 3.2 Calculate the Ir-Rh binary alloy solid solution and Ir 46 Rh1X1 solid solution in <111> Stacking fault energy curves with surface slippage along the [11-2] direction. 8 Where E0 and E b , respectively, represent the energy of a complete unit cell and a unit cell with stacking faults, A is the stacking fault area, and γ is the stacking fault; Step 3.3 Further evaluate the Ir-Rh binary alloy solid solution and Ir using the Rice standard. 46 The plasticity of Rh1X1 solid solution is shown below. 9 Where γ SUR and γ USFE These represent surface energy and unstable stacking fault energy, respectively. D is the Rice standard, and a high D value indicates better plasticity. Step 3.4 Simultaneously consider Poisson's ratio, unstable stacking fault energy, and D value to screen for effective alloying elements.

5. A method for improving the plasticity of Ir-Rh alloy according to claim 4, characterized in that: Step 4 includes: Step 4.1 The stacking fault energy of the Ir-Rh-X ternary alloy is calculated using a phase diagram method, and the concentration of alloying elements is optimized, as shown below. 10 Where x Ir x Rh and x X These represent the atomic fractions of Ir, Rh, and other alloying elements in the Ir-Rh-X ternary alloy, respectively, and γ. Ir γ Rh and γ X The stacking fault energies of Ir, Rh, and alloying elements are respectively. 0 L Ir-Rh and 0 L Ir-X These are the interaction parameters between Ir and Rh and the interaction parameters between Ir and alloying elements, respectively. Step 4.2 Using the unstable stacking fault energy of Ir-30Rh as a reference, obtain the composition range of the ternary alloy.

6. An Ir-Rh alloy prepared by a method for improving the plasticity of an Ir-Rh alloy according to any one of claims 1-5.

7. The Ir-Rh alloy according to claim 6, characterized in that: The Ir-Rh alloy is an Ir-Rh-Cu alloy with a composition range of 21.5-30.0 at.% Rh, 0.3-3.0 at.% Cu, and Ir as the balance.

8. The Ir-Rh alloy according to claim 6, characterized in that: The Ir-Rh alloy is an Ir-Rh-Zn alloy with a composition range of 23.3-30.0 at.% Rh, 0.4-3.0 at.% Zn, and Ir as the balance.

9. The Ir-Rh alloy according to claim 6, characterized in that: The Ir-Rh alloy is an Ir-Rh-Cd alloy with a composition range of 16.5-30.0 at.% Rh, 0.1-3.0 at.% Cd, and Ir as the balance.

10. The Ir-Rh alloy according to claim 6, characterized in that: The Ir-Rh alloy is an Ir-Rh-Hf alloy with a composition range of 25.2-30.0 at.% Rh, 0.1-3.0 at.% Hf, and Ir as the balance.

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