A method for manufacturing a nano-enhanced phase dispersion strengthened platinum

Abstract

The application discloses a kind of nanometer reinforcing phase dispersion strengthening platinum production methods, step one: sol preparation;Step two: platinum powder preparation;Step three: resonance coating;Step four: pressing hot forging;Step five: rolling forming;The nanometer reinforcing phase dispersion strengthening platinum production method proposed in the application, nanometer scale reinforcing phase particles are prepared using sol-gel method, after resonance coating with pure platinum powder, nanometer reinforcing phase dispersion strengthening platinum is obtained, then the defects of material are reduced by optimized pressing hot forging and rolling technology, stable texture organization is obtained, nanometer particle cluster is uniformly distributed in grain and grain boundary, according to Orowan mechanism and Hall-Petch mechanism, dislocation movement and grain growth can be effectively hindered, and the room temperature, high temperature strength of material is significantly improved and proper toughness is retained.

Description

Technical Field

[0001] This invention belongs to the field of fabrication technology of nano-reinforced phase dispersion-strengthened platinum, specifically relating to a method for fabricating nano-reinforced phase dispersion-strengthened platinum. Background Technology

[0002] With mineral resources dwindling and the price of the precious metal rhodium soaring in recent years, equipment for the glass industry using platinum and rhodium has begun to evolve towards low-rhodium and rhodium-free materials. This places higher demands on the high-temperature strength and toughness of existing dispersion-strengthened platinum materials.

[0003] The current strengthening methods adopted in the industry mainly involve introducing new strengthening elements, including Sc and Re. However, the above-mentioned process technologies still have the following shortcomings and deficiencies: (1) The use of a large amount of rare earth elements not only increases the cost of material manufacturing, but also brings about problems such as changes in glass coloring and wettability; (2) The strengthening mechanism is still the traditional alloy precipitation strengthening, but this method has limited effect on improving the strength of the material, and often reduces plasticity to improve strength; (3) Burn-off during the smelting process makes it difficult to control the content of rare earth elements. Summary of the Invention

[0004] The purpose of this invention is to provide a method for fabricating nano-reinforced phase dispersion-strengthened platinum, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A method for preparing nano-reinforced phase dispersion-strengthened platinum, step one: sol preparation: Zirconium acetate and yttrium acetate are added to the same volume of deionized water at a molar ratio of zirconium to yttrium metal ions of (5-10):1, heated and stirred in a water bath at 60-70°C, and then an ammonia solution of ethylenediaminetetraacetic acid is added dropwise until the pH value reaches 5.0-5.5. After heating and stirring for 1.0-2.0 h, an appropriate amount of acetic acid is added dropwise, and after heating and stirring for 10 min, the mixture is allowed to stand for 6.0-10.0 h to obtain a viscous colloid;

[0006] Step 2: Platinum powder preparation: Pure platinum ingots are melted in a high-frequency induction furnace, and cylindrical bars with a diameter of Ф3.0~Ф6.0mm are cast at the bottom. After being cut into small particles with a thickness of 3.0mm, pure platinum powder is prepared by electric spark plasma discharge method.

[0007] Step 3: Resonance Coating: The sol from Step 1 and the platinum powder from Step 2 are loaded into a special glass jar at a weight ratio of (1-30):1000. Then, a resonance coating machine is used to resonate the sol and platinum powder, setting the resonance frequency to 50-100Hz and the resonance time to 1-10min.

[0008] Step 4: Pressing and Hot Forging: Place the mixed powder obtained in Step 3 in an oven for 1-2 hours at a temperature of 300-400℃. After drying, place it in a mold and press it into a dense alloy ingot at room temperature and a pressure of 100-300MPa. The resulting alloy ingot is annealed at 1200-1400℃ for 20-50 minutes, and then forged 15-20 times with a 250kg air hammer to obtain a nano-reinforced phase dispersion-strengthened platinum alloy ingot.

[0009] Step 5: Rolling and forming: When the alloy ingot obtained in step 4 is rolled to 1.5 to 2 times the required thickness, it is annealed at 1100 to 1300°C for 20 to 60 minutes, and then rolled on a rolling mill to obtain the finished product of the required thickness.

[0010] Preferably, the ammonia solution of ethylenediaminetetraacetic acid in step one contains an appropriate amount of organic dispersant, wherein the organic dispersant is 10-50% by volume of polyethylene glycol-2000.

[0011] Preferably, the final particle size of the powder in step two is 5–20 μm.

[0012] Preferably, the total deformation of the alloy ingot thickness during forging in step five is 20-50%.

[0013] Preferably, the air hammer in step four, which involves 15 to 20 forgings, can be divided into two steps: initial forging and final forging. The initial forging temperature is 1300 to 1400°C, and the initial forging is performed 10 to 15 times. The final forging temperature is 1200 to 1300°C, and the final forging is performed 5 to 10 times.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention proposes a method for preparing nano-reinforced phase dispersion-strengthened platinum, which uses the sol-gel method to prepare nanoscale reinforcement phase particles, and then resonantly coats them with pure platinum powder to obtain nano-reinforced phase dispersion-strengthened platinum. Then, through optimized pressing, hot forging and rolling techniques, material defects are reduced to obtain a stable texture structure. The nanoparticle clusters are uniformly distributed within the grains and on the grain boundaries. According to the Orowan mechanism and Hall-Petch mechanism, dislocation movement and grain growth can be effectively hindered, significantly improving the room temperature and high temperature strength of the material while retaining appropriate toughness. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the sol nanoparticle size test results of the present invention;

[0016] Figure 2 This is a diagram showing the internal microstructure of the nano-reinforced phase dispersion-strengthened platinum grains of the present invention.

[0017] Figure 3 This is an enlarged view of the internal microstructure of the nano-reinforced phase dispersion-strengthened platinum grains of the present invention;

[0018] Figure 4 This is a diagram showing the microstructure of the platinum grain boundaries reinforced by the nano-reinforced phase in this invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1

[0021] (1) Sol preparation: 100 ml of zirconium acetate (15%) and yttrium acetate (15%) were added to the same volume of deionized water at a molar ratio of zirconium to yttrium metal ions of 9:1. The mixture was heated and stirred in a water bath at 65°C. Then, an ammonia solution of ethylenediaminetetraacetic acid (containing an appropriate amount of organic dispersant) was added dropwise until the pH value reached 5.1. After heating and stirring for 1.5 h, 4 ml of acetic acid was added dropwise. After heating and stirring for 10 min, the mixture was allowed to stand for 7 h to obtain a viscous colloid.

[0022] (2) Platinum powder preparation: 4 kg of pure platinum ingots were melted in a high-frequency induction furnace and cast into cylindrical bars with a diameter of Ф4.0 mm. After being cut into small particles with a thickness of 3.0 mm, pure platinum powder was prepared by electric spark plasma discharge method.

[0023] (3) Resonance coating: The sol described in step (1) and the platinum powder described in step (2) are loaded into a special glass jar at a weight ratio of 15:1000, and then a resonance coating machine is used to treat them with resonance. The resonance frequency is set to 60Hz and the resonance time is 5min.

[0024] (4) Pressing and hot forging: The mixed powder obtained in step (3) is placed in an oven for 1.5 hours at a temperature of 400°C. After drying, it is placed in a mold and pressed into a dense alloy ingot at room temperature and a pressure of 280MPa. The resulting alloy ingot is annealed at 1300°C for 30 minutes and then forged 15 times with a 250kg air hammer. The initial forging temperature is 1400°C, and the initial forging is 10 times. The final forging temperature is 1200°C, and the final forging is 5 times, to obtain a nano-reinforced phase dispersion-strengthened platinum alloy ingot.

[0025] (5) Rolling: When the alloy ingot obtained in step (4) is rolled to twice the required thickness, it is annealed at 1300°C for 30 minutes, and then rolled on a rolling mill to obtain the finished product of the required thickness.

[0026] Example 2

[0027] The preparation method is basically the same as in Example 1, except that the ratio of sol reactants is different. Zirconium acetate (15%) and yttrium acetate (15%) are added to the same volume of deionized water in a molar ratio of zirconium to yttrium metal ions of 5:1 for a total of 100 ml.

[0028] Example 3

[0029] The preparation method is basically the same as in Example 1, except that the ratio of sol to platinum powder is different. The sol and platinum powder are loaded at a weight ratio of 25:1000.

[0030] The various embodiments represent dispersion-reinforced platinum with different volume fractions of nano-reinforced phases. Specific mechanical properties are shown in the table below:

[0031] Table 1 shows the performance test results of nano-reinforced dispersion-strengthened platinum for each test case.

[0032]

[0033] Experiments have shown that the nano-reinforced phase dispersion-strengthened platinum of the present invention has the following outstanding advantages compared with traditional dispersion-strengthened platinum: the material structure is uniform and consistent, and the nanoparticle clusters are uniformly distributed within the grains and on the grain boundaries. According to the Orowan mechanism and Hall-Petch mechanism, it can effectively hinder dislocation movement and grain growth, significantly improve the room temperature and high temperature strength of the material, and retain appropriate toughness.

[0034] 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 alterations 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 method for preparing nano-reinforced phase dispersion-strengthened platinum, characterized in that: Step 1: Sol preparation: Zirconium acetate and yttrium acetate are added to an equal volume of deionized water at a molar ratio of zirconium to yttrium metal ions of (5-10):

1. The mixture is heated and stirred in a water bath at 60-70°C. Then, an ammonia solution of ethylenediaminetetraacetic acid is added dropwise until the pH value reaches 5.0-5.

5. The mixture is heated and stirred for 1.0-2.0 hours, and then an appropriate amount of acetic acid is added. The mixture is heated and stirred for 10 minutes and then allowed to stand for 6.0-10.0 hours to obtain a viscous colloid. Step 2: Platinum powder preparation: Pure platinum ingots are melted in a high-frequency induction furnace, and cylindrical bars with a diameter of Ф3.0~Ф6.0mm are cast at the bottom. After being cut into small particles with a thickness of 3.0mm, pure platinum powder is prepared by electric spark plasma discharge method. Step 3: Resonance Coating: The sol from Step 1 and the platinum powder from Step 2 are loaded into a special glass jar at a weight ratio of (1-30):1000. Then, a resonance coating machine is used to resonate the sol and platinum powder, setting the resonance frequency to 50-100Hz and the resonance time to 1-10min. Step 4: Pressing and Hot Forging: Place the mixed powder obtained in Step 3 in an oven for 1-2 hours at a temperature of 300-400℃. After drying, place it in a mold and press it into a dense alloy ingot at room temperature and a pressure of 100-300MPa. The resulting alloy ingot is annealed at 1200-1400℃ for 20-50 minutes, and then forged 15-20 times with a 250kg air hammer to obtain a nano-reinforced phase dispersion-strengthened platinum alloy ingot. Step 5: Rolling and forming: When the alloy ingot obtained in step 4 is rolled to 1.5 to 2 times the required thickness, it is annealed at 1100 to 1300°C for 20 to 60 minutes, and then rolled on a rolling mill to obtain the finished product of the required thickness.

2. The method for fabricating nano-reinforced phase dispersion-strengthened platinum according to claim 1, characterized in that: The ammonia solution of ethylenediaminetetraacetic acid in step one contains an appropriate amount of organic dispersant, wherein the organic dispersant is 10-50% by volume of polyethylene glycol-2000.

3. The method for preparing nano-reinforced phase dispersion-strengthened platinum according to claim 1, characterized in that: The final particle size of the powder mentioned in step two is 5–20 μm.

4. The method for preparing nano-reinforced phase dispersion-strengthened platinum according to claim 1, characterized in that: The total deformation amount of the alloy ingot thickness forging in step five is 20-50%.

5. The method for preparing nano-reinforced phase dispersion-strengthened platinum according to claim 1, characterized in that: Step four involves 15 to 20 forgings with the air hammer, which can be divided into two steps: initial forging and final forging. The initial forging temperature is 1300 to 1400℃, and the initial forging is performed 10 to 15 times. The final forging temperature is 1200 to 1300℃, and the final forging is performed 5 to 10 times.

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