An anti-galling agent for high-temperature performance testing of high-temperature alloys and its preparation method.

Abstract

The purpose of this invention is to provide an anti-galling agent for high-temperature performance testing of high-temperature alloys and its preparation method. The anti-galling agent is characterized by being prepared from FeCrNiCo alloy powder, graphite powder, and water. This anti-galling agent can inhibit or reduce the oxidation degree on the inner surface of the clamp and the surface of the test rod, preventing the clamp and test rod from galling and ensuring the normal conduction of high-temperature environmental testing. This invention has the advantages of simple and readily available materials, simple preparation method, non-toxicity, and convenient application, making it suitable for widespread application.

Description

Technical Field

[0001] This invention belongs to the field of high-temperature alloy technology, and specifically relates to anti-galling protection between a clamp and a test bar for testing the durability and creep properties of high-temperature alloys. Background Technology

[0002] Nickel-based single-crystal superalloys are widely used in the manufacture of turbine blades for advanced aero-engines and gas turbines due to their excellent high-temperature mechanical properties. Key performance tests of these superalloys, such as creep resistance and rupture properties, are conducted in an atmospheric environment, characterized by high temperatures, long testing times, and large quantities. Since the superalloy test bars and their clamps are typically secured by threads, both undergo oxidation under high-temperature atmospheric conditions, leading to tight seizing between the test bar and the clamp. This can make sample disassembly difficult or even render the clamp unusable. Therefore, during testing, an anti-seizing agent must be applied between the alloy test bar and the clamp to prevent seizing.

[0003] Currently, commercially available anti-seize agents are typically made of molybdenum disulfide-based, graphite-based, and ceramic-based materials. These anti-seize agents are insufficient for the performance testing requirements of high-temperature alloys, frequently causing seizing between the clamps and the test specimens, leading to experimental failures and significant waste of clamps. For example, molybdenum disulfide-based materials begin to oxidize at around 400°C in the atmosphere, after which their performance deteriorates sharply. The higher the temperature, the worse the coating performance of graphite-based materials on metal surfaces. Boron nitride-based materials begin to oxidize above 900°C, and their performance is insufficient for requirements above 1000°C.

[0004] Therefore, it is necessary to develop a new type of anti-galling agent to meet the requirements of typical high-temperature performance testing of high-temperature alloys. Summary of the Invention

[0005] The purpose of this invention is to provide an anti-galling agent for high-temperature alloy performance testing and its preparation method. The anti-galling agent can inhibit or reduce the oxidation degree of the inner surface of the clamp and the surface of the test bar, prevent the clamp and test bar from galling, and ensure the normal conduct of high-temperature environment testing.

[0006] The technical solution of this invention is as follows:

[0007] An anti-galling agent for high-temperature performance testing of high-temperature alloys, characterized in that: the anti-galling agent is composed of (FeCrNiCo). 100-x Al x It is prepared from alloy powder, graphite powder and water, wherein the ratio of each element in the alloy powder is the atomic ratio and the x value is 1-10 (more preferably 2-6).

[0008] As a preferred technical solution:

[0009] The alloy powder was prepared by ultrasonic atomization, with a powder particle size of 10-50 μm and a graphite powder particle size of 200-325 mesh.

[0010] The mass ratio of the alloy powder, graphite powder, and water is 2-4:1:1.

[0011] The anti-occlusal agent also contains 0.5-2 wt.% of an activator.

[0012] The activator is one of sodium carboxymethyl cellulose, sodium polyacrylate, tannic acid, sodium dodecylbenzene sulfonate, or sodium dodecyl sulfonate.

[0013] The method for preparing the anti-galling agent for high-temperature performance testing of high-temperature alloys according to the present invention is characterized by: mixing alloy powder and graphite powder by ball milling, mixing the alloy powder and graphite powder mixture with water to form a paste, and adding an activator to prepare the anti-galling agent.

[0014] The ball milling process is as follows: alumina grinding balls are used, the ball-to-material mass ratio is 2.5-3:1, the ball mill speed is 300-1000 rpm, and the time is 6-12 hours.

[0015] The anti-seize agent described in this invention is particularly suitable for high-temperature performance testing of high-temperature alloys. The paste-like anti-seize agent is applied between the sample and the clamp, and the sample and the clamp are fixed by threads. After the high-temperature test is completed, the test bar can be removed.

[0016] The high-temperature alloy is a directional alloy (DZ417G, DZ125 and CM247, etc.) or a single-crystal high-temperature alloy (DD413, DD33, DD6, PWA1483, CMSX-4 and CMSX-6, etc.), and the high-temperature test temperature is 950-1200℃.

[0017] The thickness of the anti-seize agent coating on the inner surface of the clamp and the fixed end surface of the test bar is controlled between 0.2-1 mm.

[0018] The anti-seize agent described in this invention can solve the problem that existing materials cannot meet the performance testing requirements of high-temperature alloys. It also has the advantages of simple and readily available materials, simple preparation methods, non-toxicity and harmlessness, and convenient application, making it suitable for widespread application. Attached Figure Description

[0019] Figure 1 The cross-section of the alloy sample after high-temperature performance testing at 1050℃ for 200 hours, with an average oxide layer thickness of 20μm (commercially available anti-galling agent).

[0020] Figure 2 The cross-section of the alloy sample after high-temperature performance testing at 1050℃ for 200 hours, with an average oxide layer thickness of 10μm (Example 1 anti-galling agent).

[0021] Figure 3 The cross-section of the alloy sample after high-temperature performance testing at 950℃ for 200 hours, with an average oxide layer thickness of 10μm (Example 2 anti-galling agent).

[0022] Figure 4 A schematic diagram of the test bar removed after the alloy high-temperature performance test at 1050℃ / 200 hours (Example 4 Anti-galling agent).

[0023] Figure 5 A schematic diagram of the test bar removed after the alloy high-temperature performance test at 1050℃ / 200 hours (commercially available anti-seize agent).

[0024] Figure 6 Comparison of two test bars after high-temperature performance testing of the alloy at 1050℃ / 200 hours.

[0025] Figure 7 The cross-section of the alloy sample after high-temperature performance testing at 1050℃ for 200 hours shows an average oxide layer thickness of 17 μm (Example 5 anti-galling agent). Detailed Implementation

[0026] Example 1

[0027] First, (FeCrNiCo) was prepared using an ultrasonic atomization method. 98 Al2 alloy powder with a particle size of 10μm and graphite powder with a particle size of 200 mesh were mixed uniformly using a ball mill with alumina grinding balls at a mass ratio of 3:1, a mill speed of 300 rpm, and a time of 6 hours. The alloy powder and graphite powder mixture was then prepared into a paste using water at a mass ratio of 2:1:1. To ensure uniform graphite distribution, 0.5% (by mass) of an activator (sodium carboxymethyl cellulose) was added to the water. After the mixture was prepared, an anti-galling agent was applied to the inner surface of the clamp and the fixed end of the test rod using a brush, with a thickness controlled at 0.2mm. The high-temperature alloy used was single-crystal alloy DD33, and the high-temperature test temperature was 1050℃. After the test, the test rod was disassembled.

[0028] After testing at 1050℃ for 200 hours, using a commercially available anti-seize agent, the average thickness of the oxide layer on the test rod surface was 20 μm. (See attached image.) Figure 1 The anti-occlusal agent prepared using this embodiment has an average oxide layer thickness of only 10 μm on the test rod surface. Figure 2 .

[0029] Example 2

[0030] First, (FeCrNiCo) was prepared using an ultrasonic atomization method. 98Al2 alloy powder with a particle size of 50 μm and graphite powder with a particle size of 325 mesh were mixed uniformly using a ball mill with alumina grinding balls at a mass ratio of 2.5:1, at a mill speed of 1000 rpm for 12 hours. The alloy powder and graphite powder mixture was then prepared into a paste using water at a mass ratio of 4:1:1. To ensure uniform graphite distribution, 2% (by mass) of activator (sodium polyacrylate) was added to the water. After the mixture was prepared, an anti-seize agent was applied to the inner surface of the clamp and the fixed end of the test rod using a brush, with a thickness controlled at 0.5 mm. The high-temperature alloy used was directional alloy DZ417, and the high-temperature test temperature was 950℃. After the test, the test rod was disassembled. Using the anti-seize agent prepared in this embodiment, the average oxide layer thickness on the test rod surface was 14 μm. (See...) Figure 3 .

[0031] Example 3

[0032] First, (FeCrNiCo) was prepared using an ultrasonic atomization method. 94 Al6 alloy powder with a particle size of 20 μm and graphite powder with a particle size of 300 mesh were mixed uniformly using a ball mill with alumina grinding balls at a mass ratio of 2.5:1, a mill speed of 800 rpm, and a time of 10 hours. The alloy powder and graphite powder mixture was then prepared into a paste using water at a mass ratio of 3:1:1. To ensure uniform graphite distribution, 1% (by mass) of activator (tannic acid) was added to the water. After the mixture was prepared, an anti-galling agent was applied to the inner surface of the clamp and the fixed end of the test rod using a brush, with a thickness controlled at 1 mm. The high-temperature alloy used was single-crystal high-temperature alloy DD413, with a high-temperature test temperature of 1000℃. The average oxide layer thickness on the test rod surface was 14 μm. After the test, the test rod could be disassembled.

[0033] Example 4

[0034] First, (FeCrNiCo) was prepared using an ultrasonic atomization method. 96Al4 alloy powder with a particle size of 30 μm and graphite powder with a particle size of 325 mesh were mixed uniformly using a ball mill with alumina grinding balls at a mass ratio of 3:1, a mill speed of 500 rpm, and a time of 10 hours. The alloy powder and graphite powder mixture was then prepared into a paste using water at a mass ratio of 2:1:1. To ensure uniform graphite distribution, 0.5% (by mass) of an activator (sodium dodecylbenzenesulfonate) was added to the water. After the mixture was prepared, an anti-galling agent was applied to the inner surface of the clamp and the fixed end of the test rod using a brush, with a thickness controlled at 0.5 mm. The high-temperature alloy used was single-crystal high-temperature alloy DD6, and the high-temperature test temperature was 1050℃. The average oxide layer thickness on the test rod surface was 12 μm. After the test, the test rod was disassembled.

[0035] like Figure 4 The image shown is a schematic diagram of a test bar removed after a high-temperature test on a sample coated with the anti-seize agent prepared in this embodiment. Figure 5 This is a schematic diagram of a test bar removed after a high-temperature test on a sample coated with a commercially available anti-seize agent. Figure 6 The image shows a comparison of the two test bars side by side. It can be seen that when commercially available anti-seize agents are used, seizing occurs between the clamp and the test bar, which prevents the experiment from proceeding normally and results in a significant waste of clamps.

[0036] Example 5

[0037] First, FeCrNiCo was prepared using an ultrasonic atomization method. )90 Al 10 Alloy powder with a particle size of 30 μm and graphite powder with a particle size of 325 mesh were used. The alloy powder and graphite powder were mixed uniformly using a ball mill with alumina grinding balls at a mass ratio of 3:1, a mill speed of 500 rpm, and a time of 10 hours. The alloy powder and graphite powder mixture was then prepared into a paste using water at a mass ratio of 2:1:1. To ensure uniform graphite distribution, 0.5% (by mass) of an activator (sodium dodecylbenzenesulfonate) was added to the water. After the mixture was prepared, an anti-galling agent was applied to the inner surface of the clamp and the fixed end of the test rod using a brush, with a thickness controlled at 0.5 mm. The high-temperature alloy used was single-crystal high-temperature alloy DD6, with a high-temperature test temperature of 1050℃. The average oxide layer thickness on the test rod surface was 17 μm. (See attached image.) Figure 7 The test rod can be disassembled after the test is completed.

[0038] Matters not covered in this invention are common knowledge.

[0039] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An anti-galling agent for high-temperature performance testing of high-temperature alloys, characterized in that: The anti-occlusive agent is composed of (FeCrNiCo). 100-x Al x It is prepared from alloy powder, graphite powder and water. The ratio of each element in the alloy powder is the atomic ratio, and the x value is 1-10. The mass ratio of the alloy powder, graphite powder, and water is 2-4:1:1; The high-temperature alloy is a directional alloy or a single-crystal high-temperature alloy, and the high-temperature test temperature is 950-1200℃.

2. The anti-galling agent for high-temperature performance testing of high-temperature alloys according to claim 1, characterized in that: The (FeCrNiCo) 100-x Al x The alloy powder has an x ​​value of 2-6 and a particle size of 10-50 μm, while the graphite powder has a particle size of 200-325 mesh.

3. The anti-galling agent for high-temperature performance testing of high-temperature alloys according to claim 1, characterized in that: The anti-occlusive agent also contains 0.5-2 wt.% of an activator.

4. The anti-galling agent for high-temperature performance testing of high-temperature alloys according to claim 3, characterized in that: The activator is one of sodium carboxymethyl cellulose, sodium polyacrylate, tannic acid, sodium dodecylbenzene sulfonate, or sodium dodecyl sulfonate.

5. A method for preparing an anti-galling agent for high-temperature performance testing of high-temperature alloys as described in claim 1, characterized in that: The alloy powder and graphite powder were mixed by ball milling, and the mixture of alloy powder and graphite powder was mixed with water to form a paste. An activator was added to prepare the anti-occlusive agent.

6. The method for preparing the anti-galling agent for high-temperature performance testing of high-temperature alloys according to claim 5, characterized in that, The ball milling process is as follows: alumina grinding balls are used, the ball-to-material mass ratio is 2.5-3:1, the ball mill speed is 300-1000 rpm, and the time is 6-12 hours.

7. The application of the anti-seize agent according to claim 6 in high-temperature performance testing of high-temperature alloys, characterized in that: The directional alloy is DZ417G, DZ125 or CM247, and the single crystal high-temperature alloy is DD413, DD33, DD6, PWA1483, CMSX-4 or CMSX-6.

8. The application of the anti-seize agent according to claim 7 in high-temperature performance testing of high-temperature alloys, characterized in that: The thickness of the anti-seize agent coating on the inner surface of the clamp and the fixed end of the test bar is controlled between 0.2-1mm.

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