Platinum-iridium-palladium-rhodium alloy material and preparation method thereof

Abstract

The invention relates to the technical field of alloy material preparation, in particular to a platinum-iridium-palladium-rhodium alloy material and a preparation method thereof. According to the scheme, the proportion of platinum, iridium, palladium and rhodium metal powder is reasonably designed, and two functional modifiers are innovatively introduced, so that the microstructure of the alloy can be effectively optimized. And a staged stepped heating smelting process is adopted, sufficient melting of the powder, decomposition strengthening phase formation of the modifier B and densification of the alloy are gradually promoted, and the uniformity and compactness of the material can be greatly improved. According to the process, refining and uniform distribution of crystal grains are controlled, internal defects and stress concentration are reduced, and the mechanical property and high temperature resistance of the alloy are enhanced. The whole technological process is scientific and rigorous, the performance stability and the service life of the platinum-iridium-palladium-rhodium alloy are remarkably improved through introduction and treatment steps of the modifier, and the platinum-iridium-palladium-rhodium alloy has good application and popularization prospects.

Description

Technical Field

[0001] This invention relates to the field of alloy material preparation technology, specifically to a platinum-iridium-palladium-rhodium alloy material and its preparation method. Background Technology

[0002] An alloy is a substance with metallic properties synthesized from two or more metals and metals or nonmetals through a specific method. Typically, the desired alloy is obtained by melting the constituent elements into a homogeneous liquid state and then solidifying it. Based on the types and numbers of constituent elements, alloys can be classified into binary alloys, ternary alloys, and multi-component alloys, among others. Platinum alloys, as an important functional material, are widely used in various fields such as temperature sensing materials, catalysts, electrical contact materials, electrode materials, elastic materials, and magnetic materials due to their excellent physicochemical properties, demonstrating broad application prospects.

[0003] However, traditional platinum alloys exhibit insufficient strength and toughness in terms of mechanical properties, making them vulnerable to mechanical stress and fatigue failure in complex environments. Hardness improvement is limited, affecting the material's wear resistance and service life. Furthermore, corrosion resistance is not ideal, especially under high-temperature and highly corrosive conditions, where performance degradation is likely, limiting their application in extreme environments. Currently, performance improvements in traditional platinum alloys mainly rely on adding one or more elements such as iridium, palladium, rhodium, aluminum, and magnesium to the platinum matrix. These elements can improve the alloy's oxidation resistance, corrosion resistance, hardness, and mechanical properties to some extent. However, the improvement effects of these added elements in existing technologies are relatively limited, often only resulting in minor performance enhancements, which are insufficient to meet the stringent requirements of high-end applications for comprehensive material performance.

[0004] Furthermore, traditional preparation processes suffer from uneven distribution of alloying elements, coarse grains, and numerous internal defects, further hindering the improvement and stability of alloy performance. Current technologies lack effective solutions for the selection of modifiers and the control of alloy microstructure, making it difficult to achieve high densification and uniform strengthening of the alloy.

[0005] Therefore, given the limitations of existing platinum alloy materials in terms of limited performance improvement, insufficient microstructure uniformity, and difficulty in meeting stringent requirements in preparation processes, there is an urgent need to develop a new, pure, and structurally optimized platinum-iridium-palladium-rhodium alloy material. This material should be combined with advanced modifier design and precisely controlled preparation processes to significantly improve the alloy's mechanical properties, hardness, and corrosion resistance, thereby meeting the higher performance requirements of high-end industrial sectors. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies, the present invention aims to provide a platinum-iridium-palladium-rhodium alloy material and its preparation method. This method effectively optimizes the microstructure of the alloy by rationally designing the ratio of platinum, iridium, palladium, and rhodium metal powders and innovatively introducing two functional modifiers. A staged, stepped heating melting process is employed to gradually promote the full melting of the powders, the formation of the decomposition strengthening phase of modifier B, and the densification of the alloy, significantly improving the material's uniformity and density. This process not only controls grain refinement and uniform distribution, reducing internal defects and stress concentration, but also enhances the alloy's mechanical properties and high-temperature resistance. The overall process is scientifically rigorous, and the introduction and treatment steps of the modifiers significantly improve the performance stability and service life of the platinum-iridium-palladium-rhodium alloy, demonstrating promising prospects for widespread application.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A platinum-iridium-palladium-rhodium alloy material comprises the following components by mass percentage: 5-10% metallic iridium powder, 3-5% metallic palladium powder, 0.5-4% metallic rhodium powder, 0.8-1.2% modifier A, 0.5-0.8% modifier B, and the balance being metallic platinum powder.

[0008] Preferably, the modifier A is prepared by the following steps: S11. Dissolve Ce(NO3)3·6H2O and Y(NO3)3·6H2O in deionized water at a mass ratio of 9-10:1-2, and stir magnetically for 30-40 minutes. S12. Add ammonia to the solution described in step S11 and adjust the pH of the solution to 9-10. Stir thoroughly for 1-2 hours to generate a precipitate. S13. Collect the precipitate, wash and dry it, and then calcine it in air for 2-3 hours to obtain the modifier A.

[0009] Preferably, in step S12, the concentration of the ammonia water is 20-25%.

[0010] Preferably, in step S13, the calcination temperature range is 700-800℃, and the heating rate is 10-15℃ / min.

[0011] Preferably, the modifier B is prepared by the following steps: S21. HfCl4, which has been vacuum dried at 180-200℃ for 12-15h, is added to the reactor. After evacuation, the atmosphere is replaced with high-purity argon to ensure an anhydrous and oxygen-free environment. S22. Inject purified and condensed liquid ammonia into the reactor to 70-80% of its volume, start stirring and cool to -80~-78℃, add NaBH4 in 4-5 portions, with an interval of 5-10 minutes between each addition, to ensure that the reaction temperature is always below -70℃ to suppress side reactions. After stirring the reaction for 6-8 hours, use the valve at the bottom of the reactor to separate the solid NaCl impurities, and retain the liquid ammonia solution containing Hf(BH4)4. S23. The liquid ammonia solution containing Hf(BH4)4 obtained by separation is transferred to a cold trap at -45~-40℃. The pressure is reduced to ≤0.1 Pa by vacuuming to remove the liquid ammonia, and white solid Hf(BH4)4 is obtained. Then, methylcyclohexane pre-cooled to -35~-30℃ is added to the solid product. After stirring thoroughly to dissolve Hf(BH4)4, the solution is filtered with a filter element with a pore size of 0.45μm to remove insoluble impurities and obtain a saturated solution of Hf(BH4)4. S24. Dissolve polymethyl methacrylate in dichloromethane to prepare a 5-10 wt% coating solution; S25. A saturated solution of Hf(BH4)4 and a PMMA solution are mixed evenly at a mass ratio of 1-2:3-4 to prepare a mixture for spray drying. The mixture is then spray dried. During the spray drying process, the droplets freeze rapidly in a low-temperature airflow. The PMMA spontaneously migrates to the surface to form a coating shell. Subsequently, dichloromethane sublimates at low temperature to form a porous microcapsule powder, thereby obtaining the modifier B.

[0012] Preferably, in steps S21 and S22, the molar ratio of HfCl4 to NaBH4 is 1:4.4-4.5.

[0013] Preferably, in step S25, the spray drying process is configured as follows: the nozzle is a two-fluid nozzle, low-temperature argon is used as the atomizing gas, the feed rate is controlled at 20-30 mL / min, the atomization pressure is 0.3-0.5 MPa, and the inlet and outlet temperatures of the spray dryer are controlled at -40~-30℃ and -50~-40℃, respectively.

[0014] A method for preparing a platinum-iridium-palladium-rhodium alloy material, comprising the following steps: S1. Weigh out the following metal powders by mass percentage: iridium powder, palladium powder, rhodium powder, modifier A, modifier B, and platinum powder. S2. Under an argon protective atmosphere, modifier A and modifier B are first mixed evenly with 10-20% of metallic platinum powder by low-speed magnetic stirring to form a coated composite powder; S3. The coated composite powder and the remaining metal powder are mixed in a closed container by a drum for 6-8 hours to ensure that the modifier is evenly distributed and undamaged. S4. Add the uniformly mixed powder into the melting furnace and perform a stepped heating process to obtain the alloy liquid; S5. After removing the slag from the alloy liquid, keep it at a constant temperature for 30-40 minutes, pour it into a mold for casting, anneal at 1000-1200℃ for 1-2 hours, and cool it to room temperature to obtain the platinum-iridium-palladium-rhodium alloy material.

[0015] Preferably, in step S4, the stepped heating process employs the following heating and holding steps: Heat to 700-800℃ and hold for 10-15 minutes to promote the initial melting of the powder; Continue heating to 1300-1400℃ and hold at this temperature for 20-30 minutes to promote the decomposition of modifier B and generate the reinforcing phase. Continue heating to 1700-1800℃ and hold at this temperature for 30-35 minutes to fully complete the densification process; Continue heating to 2500-2600℃ and hold at this temperature for 50-60 minutes to obtain the alloy liquid.

[0016] Preferably, in step S5, the casting temperature is 2000-2200℃ and the casting speed is 30-40mm / min.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention significantly optimizes the microstructure and macroscopic properties of platinum-iridium-palladium-rhodium alloys by introducing two highly functional modifiers and leveraging the synergistic effect of nano-composite oxide particles and microcapsule-encapsulated reinforcing phases. Modifier A is uniformly distributed within the alloy matrix in the form of nano-composite oxide particles. These nanoparticles possess extremely high specific surface area and thermal stability, effectively inhibiting grain growth and grain boundary migration, thereby refining grain size, improving grain boundary strength and overall toughness, and significantly enhancing the material's resistance to deformation and ductility. Furthermore, the nano-oxide particles themselves possess excellent antioxidant properties, forming a dense and stable oxide protective film at high temperatures, effectively blocking the intrusion of oxygen and corrosive media, improving the alloy's thermal stability and corrosion resistance, and ensuring stable performance and long service life under extreme conditions. Modifier B employs advanced microencapsulation technology to uniformly encapsulate the active Hf element precursor within a polymer shell, achieving uniform distribution and controlled slow release of Hf. This design effectively avoids common problems such as segregation, agglomeration, and uneven distribution when directly adding Hf, ensuring the uniform formation of the reinforcing phase. During high-temperature melting, the encapsulated shell gradually decomposes, releasing Hf, which promotes the fine and uniform precipitation of the reinforcing phase within the alloy matrix. These dispersed reinforcing phase particles significantly improve the alloy's strength and fatigue resistance by hindering dislocation movement and grain boundary slip, effectively enhancing the material's ability to resist external mechanical loads. Simultaneously, the presence of the reinforcing phase improves the alloy's thermal stability, reduces grain growth and performance degradation at high temperatures, further improving the alloy's corrosion resistance and service life, ensuring its reliability and stability in harsh environments such as high-temperature and highly corrosive conditions.

[0018] 2. This solution employs a stepped heating process, precisely controlling temperature and holding time to promote complete melting of the powder and effective decomposition of the modifier, achieving uniform precipitation of the strengthening phase and high densification of the alloy. This process not only reduces internal porosity and defects but also effectively alleviates thermal stress, ensuring the uniformity and stability of the alloy melt, further improving the material's performance and lifespan. Attached Figure Description

[0019] Figure 1 This is a flowchart illustrating the preparation process of the ultrafine holmium oxide nanomaterials described in this invention. Figure 2 This is a flow chart of the preparation process of the modifier A described in this invention; Figure 3 This is a flowchart illustrating the preparation process of the modifier B described in this invention. Figure 4 Here is a SEM image of the modifier A prepared in Example 1 of this invention; Figure 5 This is a SEM image of the modifier B prepared in Example 1 of the present invention. Detailed Implementation

[0020] The present invention will now be clearly and completely described in conjunction with embodiments thereof. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0021] Please see Figure 1-5 The present invention provides a technical solution: Example 1: This example provides a platinum-iridium-palladium-rhodium alloy material, which is composed of the following components by mass percentage: 5% metallic iridium powder, 3% metallic palladium powder, 1.25% metallic rhodium powder, 0.8% modifier A, 0.5% modifier B, and the balance component is metallic platinum powder.

[0022] The modifier A is prepared by the following steps: S11. Dissolve Ce(NO3)3·6H2O and Y(NO3)3·6H2O in deionized water at a mass ratio of 10:1 and stir magnetically for 30 min. S12. Add 20% ammonia solution to the solution described in step S11, adjust the pH of the solution to 9, and stir thoroughly for 1.5 hours to generate a precipitate; S13. Collect the precipitate, wash and dry it, then heat it to 700°C at a rate of 10°C / min and calcine it in air for 2 hours to obtain the modifier A.

[0023] The modifier B is prepared by the following steps: S21. HfCl4, which has been vacuum dried at 200℃ for 12h, is added to the reactor. After evacuation, the atmosphere is replaced with high-purity argon to ensure an anhydrous and oxygen-free environment. S22. Inject purified and condensed liquid ammonia into the reactor to 80% of its volume, start stirring and cool to -78℃, add NaBH4 in 4 portions, with an interval of 10 minutes between each addition, to ensure that the reaction temperature is always below -70℃ to suppress side reactions. After stirring the reaction for 8 hours, use the valve at the bottom of the reactor to separate the solid NaCl impurities, and retain the liquid ammonia solution containing Hf(BH4)4. S23. The liquid ammonia solution containing Hf(BH4)4 obtained by separation is transferred to a cold trap at -40℃. The pressure is reduced to ≤0.1 Pa by vacuuming to remove the liquid ammonia, and white solid Hf(BH4)4 is obtained. Then, methylcyclohexane pre-cooled to -30℃ is added to the solid product. After stirring thoroughly to dissolve Hf(BH4)4, the solution is filtered with a filter element with a pore size of 0.45μm to remove insoluble impurities and obtain a saturated solution of Hf(BH4)4. S24. Dissolve polymethyl methacrylate in dichloromethane to prepare a 7.5 wt% coating solution; S25. A saturated solution of Hf(BH4)4 and a PMMA solution are mixed evenly at a mass ratio of 1:4 to prepare a mixture for spray drying. The mixture is then spray dried. During the spray drying process, the droplets freeze rapidly in a low-temperature airflow. The PMMA spontaneously migrates to the surface to form a coating shell. Subsequently, dichloromethane sublimates at low temperature to form a porous microcapsule powder, thereby obtaining the modifier B.

[0024] In the preparation process of the modifier B, in steps S21 and S22, the molar ratio of HfCl4 to NaBH4 is 1:4.4; in step S25, the spray drying process is set as follows: the nozzle is a two-fluid nozzle, low-temperature argon is used as the atomizing gas, the feed rate is controlled at 20 mL / min, the atomization pressure is 0.5 MPa, and the inlet and outlet temperatures of the spray dryer are controlled at -30℃ and -50℃, respectively.

[0025] This embodiment also provides a method for preparing a platinum-iridium-palladium-rhodium alloy material, which specifically includes the following steps: S1. Weigh out the following metal powders by mass percentage: iridium powder, palladium powder, rhodium powder, modifier A, modifier B, and platinum powder. S2. Under an argon protective atmosphere, modifier A and modifier B are first mixed evenly with 10% platinum powder by low-speed magnetic stirring to form a coated composite powder; S3. The coated composite powder and the remaining metal powder are mixed in a closed container by a drum for 8 hours to ensure that the modifier is evenly distributed and undamaged. S4. Add the uniformly mixed powder into the melting furnace and perform a stepped heating process to obtain the alloy liquid; S5. After removing the slag from the alloy liquid, keep it at a constant temperature for 30 minutes, pour it into a mold for casting, anneal at 1100℃ for 2 hours, and cool to room temperature to obtain the platinum-iridium-palladium-rhodium alloy material.

[0026] In step S4, the stepped heating process employs the following heating and holding steps: Heat to 800℃ and hold for 15 minutes to promote the initial melting of the powder; Continue heating to 1300℃ and hold at this temperature for 20 minutes to promote the decomposition of modifier B and generate the reinforcing phase. Continue heating to 1800℃ and hold at this temperature for 30 minutes to fully complete the densification process; The temperature was further increased to 2600℃ and held at this temperature for 60 minutes to obtain the alloy liquid.

[0027] In step S5, the casting temperature is 2000℃ and the casting speed is 30mm / min.

[0028] Example 2: Example 2 differs from Example 1 in that, in Example 2, the platinum-iridium-palladium-rhodium alloy material comprises the following components by mass percentage: 8% metallic iridium powder, 4% metallic palladium powder, 2% metallic rhodium powder, 1.2% modifier A, 0.8% modifier B, and the balance component is metallic platinum powder. The remaining steps are exactly the same as in Example 2 and Example 1.

[0029] Example 3: Example 3 differs from Example 1 in that, in Example 3, the platinum-iridium-palladium-rhodium alloy material comprises the following components by mass percentage: 10% metallic iridium powder, 4.5% metallic palladium powder, 3% metallic rhodium powder, 1% modifier A, 0.6% modifier B, and the balance component is metallic platinum powder. The remaining steps are exactly the same as in Example 3 and Example 1.

[0030] Comparative Example, Comparative Example 1: The only difference between Comparative Example 1 and Example 1 is that the use of modifier A was omitted in Comparative Example 1, while the other steps are exactly the same in Comparative Example 1 and Example 1.

[0031] Comparative Example 2: The only difference between Comparative Example 2 and Example 1 is that the use of modifier B was omitted in Comparative Example 2. The remaining steps are exactly the same in Comparative Example 2 and Example 1.

[0032] Comparative Example 3: The only difference between Comparative Example 3 and Example 1 is that the use of Modifier A and Modifier B was omitted in Comparative Example 3. The remaining steps are exactly the same in Comparative Example 3 and Example 1.

[0033] Performance testing: The SEM image of modifier A prepared in Example 1 of this invention is shown below. Figure 4 As shown in the figure, modifier A consists of a large number of uniformly sized and evenly distributed nanoparticles, with particle sizes ranging from 10 to 50 nanometers. The particle boundaries are clear, and they are tightly packed together, with no obvious agglomeration or large particle aggregation, indicating good dispersibility. The particle surfaces are dense and uniform, with no obvious pores or cracks observed, demonstrating good crystallinity and thermal stability.

[0034] The SEM image of the modifier B prepared in Example 1 of this invention is shown below. Figure 5 As shown in the figure, the particles exhibit a relatively regular spherical shape with a uniform particle size distribution, ranging from approximately 20 to 60 micrometers. The particle surface is generally rough, with some particles showing fine wrinkles or cracks, presumably due to drying during the preparation process or the sublimation of dichloromethane at low temperatures. The particles are uniformly distributed without obvious agglomeration, demonstrating good dispersibility and stability, which is beneficial for achieving uniform doping and stable release of Hf element during application.

[0035] The mechanical properties of the alloy materials in Examples 1-3 and Comparative Examples 1-3 were tested according to the requirements of GB / T 228.1-2010 standard; the hardness of the alloy materials in Examples 1-3 and Comparative Examples 1-3 was tested according to the requirements of GB / T 4342-1991 standard; and the corrosion resistance of the alloy materials in Examples 1-3 and Comparative Examples 1-3 was tested according to the requirements of GB / T 10125-2012 standard. The test results are shown below:

[0036] As can be seen from the above, the alloy materials of Examples 1-3 are significantly superior to those of Comparative Examples 1-3 in terms of mechanical strength, hardness, and corrosion resistance. In Examples 2 and 3, the content of modifier A and modifier B is increased compared to Example 1, resulting in more uniform formation of the strengthening phase and finer grains, thereby improving the tensile strength and yield strength of the alloy, while also increasing the hardness. The elongation is moderately reduced, exhibiting a typical trend of slightly decreasing toughness during the process of increasing material strength.

[0037] Comparative Example 1, by omitting modifier A, resulted in the absence of nanocomposite oxide particles, weakened grain refinement, and decreased grain boundary stability. Consequently, its tensile strength and hardness were significantly lower than in Example 1, and its elongation was also reduced. Comparative Example 2, by omitting modifier B, resulted in insufficient Hf-based reinforcing phases, reduced dislocation hindering ability of the material, leading to decreased strength and hardness, as well as a significant decrease in corrosion resistance. Comparative Example 3, without the addition of modifiers A and B, exhibited the worst overall material performance, demonstrating that the synergistic effect of modifiers is crucial for improving alloy performance.

[0038] Corrosion resistance tests showed that the rare earth oxides in modifier A effectively formed a stable antioxidant protective layer, while modifier B improved the microstructure density by reinforcing the uniform distribution of the phase, reducing the penetration pathway of the corrosive medium and thus significantly reducing the corrosion rate. Example 3 had the highest modifier content, resulting in the best corrosion resistance and the lowest corrosion rate; while Comparative Example 3, lacking both modifier A and modifier B, did not have the relevant corrosion resistance mechanism, thus exhibiting the highest corrosion rate.

[0039] In summary, this technical solution, by introducing modifier A and modifier B, not only improves the mechanical properties and hardness of the platinum-iridium-palladium-rhodium alloy, but also significantly enhances its thermal stability and corrosion resistance at high temperatures. This fully demonstrates the synergistic strengthening effect of the two modifiers and their comprehensive improvement on the alloy's performance, possessing strong engineering application value and promotion potential.

[0040] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A platinum-iridium-palladium-rhodium alloy material, characterized in that, The composition by mass percentage includes the following components: 5-10% iridium powder, 3-5% palladium powder, 0.5-4% rhodium powder, 0.8-1.2% modifier A, 0.5-0.8% modifier B, and the balance being platinum powder.

2. The platinum-iridium-palladium-rhodium alloy material according to claim 1, characterized in that, The modifier A is prepared by the following steps: S11. Dissolve Ce(NO3)3·6H2O and Y(NO3)3·6H2O in deionized water at a mass ratio of 9-10:1-2, and stir magnetically for 30-40 minutes. S12. Add ammonia to the solution described in step S11 and adjust the pH of the solution to 9-10. Stir thoroughly for 1-2 hours to generate a precipitate. S13. Collect the precipitate, wash and dry it, and then calcine it in air for 2-3 hours to obtain the modifier A.

3. The platinum-iridium-palladium-rhodium alloy material according to claim 2, characterized in that, In step S12, the concentration of the ammonia water is 20-25%.

4. The platinum-iridium-palladium-rhodium alloy material according to claim 3, characterized in that, In step S13, the calcination temperature range is 700-800℃, and the heating rate is 10-15℃ / min.

5. The platinum-iridium-palladium-rhodium alloy material according to claim 1, characterized in that, The modifier B is prepared by the following steps: S21. HfCl4, which has been vacuum dried at 180-200℃ for 12-15h, is added to the reactor. After evacuation, the atmosphere is replaced with high-purity argon to ensure an anhydrous and oxygen-free environment. S22. Inject purified and condensed liquid ammonia into the reactor to 70-80% of its volume, start stirring and cool to -80~-78℃, add NaBH4 in 4-5 portions, with an interval of 5-10 minutes between each addition, to ensure that the reaction temperature is always below -70℃ to suppress side reactions. After stirring the reaction for 6-8 hours, use the valve at the bottom of the reactor to separate the solid NaCl impurities, and retain the liquid ammonia solution containing Hf(BH4)4. S23. The liquid ammonia solution containing Hf(BH4)4 obtained by separation is transferred to a cold trap at -45~-40℃. The pressure is reduced to ≤0.1 Pa by vacuuming to remove the liquid ammonia, and white solid Hf(BH4)4 is obtained. Then, methylcyclohexane pre-cooled to -35~-30℃ is added to the solid product. After stirring thoroughly to dissolve Hf(BH4)4, the solution is filtered with a filter element with a pore size of 0.45μm to remove insoluble impurities and obtain a saturated solution of Hf(BH4)4. S24. Dissolve polymethyl methacrylate in dichloromethane to prepare a 5-10 wt% coating solution; S25. A saturated solution of Hf(BH4)4 and a PMMA solution are mixed evenly at a mass ratio of 1-2:3-4 to prepare a mixture for spray drying. The mixture is then spray dried. During the spray drying process, the droplets freeze rapidly in a low-temperature airflow. The PMMA spontaneously migrates to the surface to form a coating shell. Subsequently, dichloromethane sublimates at low temperature to form a porous microcapsule powder, thereby obtaining the modifier B.

6. The platinum-iridium-palladium-rhodium alloy material according to claim 5, characterized in that, In steps S21 and S22, the molar ratio of HfCl4 to NaBH4 is 1:4.4-4.

5.

7. The platinum-iridium-palladium-rhodium alloy material according to claim 5, characterized in that, In step S25, the spray drying process is set as follows: the nozzle is a two-fluid nozzle, low-temperature argon is used as the atomizing gas, the feed rate is controlled at 20-30 mL / min, the atomization pressure is 0.3-0.5 MPa, and the inlet and outlet temperatures of the spray dryer are controlled at -40~-30℃ and -50~-40℃, respectively.

8. A method for preparing a platinum-iridium-palladium-rhodium alloy material, used to prepare the platinum-iridium-palladium-rhodium alloy material according to any one of claims 1-7, characterized in that, Includes the following steps: S1. Weigh out the following metal powders by mass percentage: iridium powder, palladium powder, rhodium powder, modifier A, modifier B, and platinum powder. S2. Under an argon protective atmosphere, modifier A and modifier B are first mixed evenly with 10-20% of metallic platinum powder by low-speed magnetic stirring to form a coated composite powder; S3. The coated composite powder and the remaining metal powder are mixed in a closed container by a drum for 6-8 hours to ensure that the modifier is evenly distributed and undamaged. S4. Add the uniformly mixed powder into the melting furnace and perform a stepped heating process to obtain the alloy liquid; S5. After removing the slag from the alloy liquid, keep it at a constant temperature for 30-40 minutes, pour it into a mold for casting, anneal at 1000-1200℃ for 1-2 hours, and cool it to room temperature to obtain the platinum-iridium-palladium-rhodium alloy material.

9. The method for preparing a platinum-iridium-palladium-rhodium alloy material according to claim 8, characterized in that, In step S4, the stepped heating process employs the following heating and holding steps: Heat to 700-800℃ and hold for 10-15 minutes to promote the initial melting of the powder; Continue heating to 1300-1400℃ and hold at this temperature for 20-30 minutes to promote the decomposition of modifier B and generate the reinforcing phase. Continue heating to 1700-1800℃ and hold at this temperature for 30-35 minutes to fully complete the densification process; Continue heating to 2500-2600℃ and hold at this temperature for 50-60 minutes to obtain the alloy liquid.

10. The method for preparing a platinum-iridium-palladium-rhodium alloy material according to claim 8, characterized in that, In step S5, the casting temperature is 2000-2200℃ and the casting speed is 30-40mm / min.

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