Rust prevention method for powder metallurgy part
By using anti-rust oil with good oil-water separation and dehydration, combined with oil-absorbing cotton, magnetic rods and high-temperature drying treatment, the problem of powder metallurgy parts prone to rust in high-temperature and high-humidity environments is solved, and the anti-rust effect is significantly improved .
Patent Information
- Application Number
- CN202411464867.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-21
- Publication Date
- 2025-02-18
AI Technical Summary
Powder metallurgical parts are prone to rust in high temperature and high humidity environments. The existing anti-rust methods lack oil-water separation and dehydration properties, resulting in poor anti-rust effect.
Use anti-rust oil with good oil-water separation and dehydration properties, and improve the anti-rust effect of parts by setting up oil-absorbing cotton and magnetic rods in the cleaning machine, combining high-temperature drying and oil-soaking treatment.
It significantly improves the anti-rust effect of powder metallurgical parts, can keep the parts from rust in moisture and heat and salt spray tests, and extends the service life of the parts.
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of powder metallurgy, and in particular to a method for preventing rust of powder metallurgy parts. Background Art
[0002] Powder metallurgy is a process that uses a mixture of metal powder (or a mixture of metal powder and non-metallic powder) as raw material to produce metal materials, composite materials and various products through molding and sintering processes.
[0003] Powder metallurgy technology can produce complex shapes and structures, achieve design flexibility, meet the requirements of material properties and shapes in different application fields, and is suitable for mass production of precision and complex parts. This makes powder metallurgy technology widely used in many fields such as automobile manufacturing, electronic equipment, and aerospace.
[0004] The process of powder metallurgy determines that powder metallurgy is a porous structure product. This porous structure makes it difficult to remove moisture from the product, especially in high temperature and high humidity seasons, it is particularly prone to rust, so timely rust prevention measures need to be taken, but the rust prevention methods in the prior art have insufficient oil absorption during the cleaning process, and the oil-water separation and dehydration properties of the rust-proof oil are also insufficient, resulting in poor rust prevention effect on the treated powder metallurgy parts. Summary of the invention
[0005] The purpose of the present invention is to provide a method for preventing rust of powder metallurgy parts, which is configured with rust-proof oil having good oil-water separation and dehydration properties, and can improve the rust-proof effect of the parts after immersion.
[0006] In order to achieve the above object, the present invention provides the following technical solution: a method for rust prevention of powder metallurgy parts, the specific steps are as follows: S1: cleaning process; 1.1: Place the parts made by powder metallurgy under the fan for blowing to remove some impurities attached to the surface; 1.2: After purging, the parts are placed in the cleaning tank of the cleaning machine for cleaning. Each cleaning tank is equipped with oil-absorbing cotton and magnetic rods. The oil-absorbing cotton can absorb the oil during the cleaning process, and the oil absorption rate is more than 7 times that of the existing technology. The magnetic rod can absorb the dirt during the cleaning process; 1.3: New water is continuously added to the cleaning tank during cleaning. The cleaning time lasts for 5-12 minutes. The water temperature during cleaning is controlled at 30-60℃. Properly increasing the water temperature can increase the effect of oil removal. S2: Drying process: 2.1: Take the cleaned parts out of the cleaning machine and wipe the surface of the parts dry with a cloth that has water absorption capacity. The cloth can be a cotton cloth with good water absorption effect to prevent it from dripping and improve the drying efficiency; 2.2: The wiped parts are placed in the drying section for further drying. During drying, hot air at 50-70°C is blown to the surface of the workpiece for 3-10 minutes to reduce the moisture content of the parts. S3: oil immersion process; 3.1: Choose anti-rust oil with good oil-water separation and dehydration properties; 3.2: Heat the anti-rust oil to 80-120℃, then immerse the dried parts in the anti-rust oil for 40-70 minutes; 3.3: After soaking, take the parts out of the anti-rust oil and drain the anti-rust oil on the surface of the parts to prevent the parts from carrying the anti-rust oil and causing the anti-rust oil to drip everywhere. Then let the parts stand at room temperature to cool for 15-30 minutes; 3.4: Randomly select multiple samples from the cooled parts, and subject them to wet heat test and salt spray test. If all samples are not rusted after two tests, it means that this batch of parts is qualified. If rust occurs, it is unqualified. The unqualified parts of the same batch need to be treated with rust prevention again. If they are still unqualified after three rust prevention treatments, they will be recycled and destroyed; S4: Full appearance inspection; 4.1: Place the parts after the oil immersion process on a turntable with a protective cover and inspect the appearance. The full inspection area is in a closed state. The humidity in the full inspection area is controlled at 30-50%, and the temperature is maintained at 15-25℃. On-site personnel are equipped with sweat-proof sleeves, gloves and masks. After the full appearance inspection is qualified, all parts can be completely rust-proofed.
[0007] Furthermore, the cleaning machine in S1 is provided with four cleaning tanks, which are detected by a liquid level sensor and automatically discharged to tank 3 by a water pump to ensure that the water in tank 3 is clean and new water is continuously added.
[0008] Furthermore, the drying section in S2 is separate and longer than the conventional drying section.
[0009] Furthermore, the anti-rust oil in S3 must be kept flowing during the soaking process of the parts, and the mixed water-based liquid in the anti-rust oil must be removed regularly. At the same time, the anti-rust oil needs to be regularly replenished and replaced. During the soaking process of the parts, cooling water is also needed to cool the anti-rust oil to ensure that the temperature of the anti-rust oil is within the set range, and the filter bag for filtering the anti-rust oil needs to be replaced once a day; Only the sample needs to be processed in 3.4 in S3, and other parts do not need to be tested. However, it is necessary to wait for the results of the sample test. Only after passing the test can S4 be carried out.
[0010] Furthermore, the wet heat test in S3 is to place the parts in a wet heat environment at 50°C for 4 hours, and the salt spray test is to spray a 0.5% NaCL solution on the parts after atomization for 30 minutes; Parts samples that have passed two tests must go through S1, S2, and S3 again even if they are qualified.
[0011] Furthermore, the protective shield in the S4 needs to be wiped down every two hours.
[0012] Further, the raw materials of the rust-proof oil in 3.1 are respectively as follows in parts by weight: 100 parts of synthetic oil, 30 parts of rust-proof agent, 10 parts of diaryl secondary amine, 10 parts of organic acid salt, 5 parts of chemical demulsifier and 5 parts of anhydrous calcium chloride; The synthetic oil, the rust inhibitor, the diaryl secondary amine and the organic acid salt are the basic components of the traditional rust-proof oil. The raw materials of the traditional rust-proof oil are 100 parts of the synthetic oil, 30 parts of the rust inhibitor, 10 parts of the diaryl secondary amine and 10 parts of the organic acid salt in parts by weight. The extra chemical demulsifier in the rust-proof oil of the invention can reduce the stability of the emulsion, thereby improving the oil-water separation property of the rust-proof oil, and the anhydrous calcium chloride can absorb water, reduce the reaction between water and metal parts, thereby improving the dehydration property of the rust-proof oil.
[0013] In the above technical solution, the technical effects and advantages provided by the present invention are: 1. By installing oil-absorbing cotton and magnetic rods inside each cleaning tank, the oil absorption rate is more than 7 times that of the existing technology, and the dirt in the cleaning process is absorbed. At the same time, the liquid level sensor detects and automatically discharges the water in tank 4 to tank 3 through a water pump to ensure that the water in tank 3 is clean and new water is continuously added, so that the cleaning effect of the parts is better, and the anti-rust effect after treatment is also better; 2. Choose anti-rust oil with good oil-water separation and dehydration properties. After soaking, it can improve the anti-rust effect of parts. In addition, the control requirements for the frequency of filter bag replacement have been updated, changing once a week to once a day, which improves the performance of anti-rust oil and thus improves the anti-rust effect of parts. DETAILED DESCRIPTION
[0014] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below. Example
[0015] The present invention provides a method for rust prevention of powder metallurgy parts, and the specific steps are as follows: S1: cleaning process; 1.1: Place the parts made by powder metallurgy under the fan for blowing to remove some impurities attached to the surface; 1.2: After purging, the parts are placed in the cleaning tank of the cleaning machine for cleaning, and each cleaning tank is equipped with oil-absorbing cotton and magnetic rods; 1.3: New water is continuously added to the cleaning tank during cleaning. The cleaning time lasts for 5 minutes and the water temperature during cleaning is controlled at 30°C. S2: Drying process: 2.1: Take the cleaned parts out of the cleaning machine and wipe the surface of the parts dry with a cloth that has water absorption capacity so that it no longer drips; 2.2: The wiped parts are placed in the drying section for further drying. During drying, 50°C hot air is blown to the surface of the workpiece for 3 minutes to reduce the moisture content of the parts; S3: oil immersion process; 3.1: Use anti-rust oil, the raw materials of which include 100 parts of synthetic oil, 30 parts of rust inhibitor, 10 parts of diaryl secondary amine, 10 parts of organic acid salt, 5 parts of chemical demulsifier and 5 parts of anhydrous calcium chloride by weight; 3.2: Heat the anti-rust oil to 80°C, then soak the dried parts in the anti-rust oil for 40 minutes; 3.3: After soaking, take the parts out of the anti-rust oil and drain the anti-rust oil on the surface of the parts, then let the parts stand at room temperature to cool for 15 minutes; 3.4: Randomly select multiple samples from the cooled parts and subject them to damp heat test and salt spray test. The damp heat test is to place the parts in a damp heat environment of 50℃ for 4 hours. The salt spray test is to spray a 0.5% NaCL solution on the parts after atomization for 30 minutes. If all samples are not rusted after the two tests, it means that the batch of parts is qualified. If rust occurs, it is unqualified. S4: Full appearance inspection; 4.1: Place the parts after the oil immersion process on a turntable with a protective cover and inspect the appearance. The full inspection area is in a closed state. The humidity in the full inspection area is controlled at 30%, and the temperature is maintained at 15°C. On-site personnel are equipped with sweat-proof sleeves, gloves and masks. After the full appearance inspection is qualified, all parts can be completely rust-proofed. Example
[0016] The present invention provides a method for rust prevention of powder metallurgy parts, and the specific steps are as follows: S1: cleaning process; 1.1: Place the parts made by powder metallurgy under the fan for blowing to remove some impurities attached to the surface; 1.2: After purging, the parts are placed in the cleaning tank of the cleaning machine for cleaning, and each cleaning tank is equipped with oil-absorbing cotton and magnetic rods; 1.3: New water is continuously added to the cleaning tank during cleaning. The cleaning time lasts for 8 minutes, and the water temperature during cleaning is controlled at 40°C; S2: Drying process: 2.1: Take the cleaned parts out of the cleaning machine and wipe the surface of the parts dry with a cloth that has water absorption capacity so that it no longer drips; 2.2: The wiped parts are placed in the drying section for further drying. During drying, 55°C hot air is blown to the surface of the workpiece for 5 minutes to reduce the moisture content of the parts; S3: oil immersion process; 3.1: Use anti-rust oil, the raw materials of which include 100 parts of synthetic oil, 30 parts of rust inhibitor, 10 parts of diaryl secondary amine, 10 parts of organic acid salt, 5 parts of chemical demulsifier and 5 parts of anhydrous calcium chloride by weight; 3.2: Heat the anti-rust oil to 95°C, then soak the dried parts in the anti-rust oil for 50 minutes; 3.3: After soaking, take the parts out of the anti-rust oil and drain the anti-rust oil on the surface of the parts, then let the parts stand at room temperature to cool for 20 minutes; 3.4: Randomly select multiple samples from the cooled parts and subject them to damp heat test and salt spray test. The damp heat test is to place the parts in a damp heat environment of 50℃ for 4 hours. The salt spray test is to spray a 0.5% NaCL solution on the parts after atomization for 30 minutes. If all samples are not rusted after the two tests, it means that the batch of parts is qualified. If rust occurs, it is unqualified. S4: Full appearance inspection; 4.1: Place the parts after the oil immersion process on a turntable with a protective cover and inspect the appearance. The full inspection area is in a closed state. The humidity in the full inspection area is controlled at 35%, and the temperature is maintained at 18°C. On-site personnel are equipped with sweat-proof sleeves, gloves and masks. After the full appearance inspection is qualified, all parts can be completely rust-proofed. Example
[0017] The present invention provides a method for rust prevention of powder metallurgy parts, and the specific steps are as follows: S1: cleaning process; 1.1: Place the parts made by powder metallurgy under the fan for blowing to remove some impurities attached to the surface; 1.2: After purging, the parts are placed in the cleaning tank of the cleaning machine for cleaning, and each cleaning tank is equipped with oil-absorbing cotton and magnetic rods; 1.3: New water is continuously added to the cleaning tank during cleaning. The cleaning time lasts for 10 minutes and the water temperature during cleaning is controlled at 50°C; S2: Drying process: 2.1: Take the cleaned parts out of the cleaning machine and wipe the surface of the parts dry with a cloth that has water absorption capacity so that it no longer drips; 2.2: The wiped parts are placed in the drying section for further drying. During drying, hot air at 65°C is blown to the surface of the workpiece for 8 minutes to reduce the moisture content of the parts; S3: oil immersion process; 3.1: Use anti-rust oil, the raw materials of which include 100 parts of synthetic oil, 30 parts of rust inhibitor, 10 parts of diaryl secondary amine, 10 parts of organic acid salt, 5 parts of chemical demulsifier and 5 parts of anhydrous calcium chloride by weight; 3.2: Heat the anti-rust oil to 110°C, then soak the dried parts in the anti-rust oil for 60 minutes; 3.3: After soaking, take the parts out of the anti-rust oil and drain the anti-rust oil on the surface of the parts, then let the parts stand at room temperature to cool for 25 minutes; 3.4: Randomly select multiple samples from the cooled parts and subject them to damp heat test and salt spray test. The damp heat test is to place the parts in a damp heat environment of 50℃ for 4 hours. The salt spray test is to spray a 0.5% NaCL solution on the parts after atomization for 30 minutes. If all samples are not rusted after the two tests, it means that the batch of parts is qualified. If rust occurs, it is unqualified. S4: Full appearance inspection; 4.1: Place the parts after the oil immersion process on a turntable with a protective cover and inspect the appearance. The full inspection area is in a closed state. The humidity in the full inspection area is controlled at 45%, and the temperature is maintained at 22°C. On-site personnel are equipped with sweat-proof sleeves, gloves and masks. After the full appearance inspection is qualified, all parts can be completely rust-proofed. Example
[0018] The present invention provides a method for rust prevention of powder metallurgy parts, and the specific steps are as follows: S1: cleaning process; 1.1: Place the parts made by powder metallurgy under the fan for blowing to remove some impurities attached to the surface; 1.2: After purging, the parts are placed in the cleaning tank of the cleaning machine for cleaning, and each cleaning tank is equipped with oil-absorbing cotton and magnetic rods; 1.3: New water is continuously added to the cleaning tank during cleaning. The cleaning time lasts for 12 minutes and the water temperature during cleaning is controlled at 60°C. S2: Drying process: 2.1: Take the cleaned parts out of the cleaning machine and wipe the surface of the parts dry with a cloth that has water absorption capacity so that it no longer drips; 2.2: The wiped parts are placed in the drying section for further drying. During drying, hot air at 70°C is blown to the surface of the workpiece for 10 minutes to reduce the moisture content of the parts. S3: oil immersion process; 3.1: Use anti-rust oil, the raw materials of which include 100 parts of synthetic oil, 30 parts of rust inhibitor, 10 parts of diaryl secondary amine, 10 parts of organic acid salt, 5 parts of chemical demulsifier and 5 parts of anhydrous calcium chloride by weight; 3.2: Heat the anti-rust oil to 120°C, then immerse the dried parts in the anti-rust oil for 70 minutes; 3.3: After soaking, take the parts out of the anti-rust oil and drain the anti-rust oil on the surface of the parts, then let the parts stand at room temperature to cool for 30 minutes; 3.4: Randomly select multiple samples from the cooled parts and subject them to damp heat test and salt spray test. The damp heat test is to place the parts in a damp heat environment of 50℃ for 4 hours. The salt spray test is to spray a 0.5% NaCL solution on the parts after atomization for 30 minutes. If all samples are not rusted after the two tests, it means that the batch of parts is qualified. If rust occurs, it is unqualified. S4: Full appearance inspection; 4.1: Place the parts after the oil immersion process on a turntable with a protective cover and inspect the appearance. The full inspection area is in a closed state. The humidity in the full inspection area is controlled at 50%, and the temperature is maintained at 25°C. On-site personnel are equipped with sweat-proof sleeves, gloves and masks. After the full appearance inspection is qualified, all parts can be completely rust-proofed. Example
[0019] The present invention provides a method for rust prevention of powder metallurgy parts, and the specific steps are as follows: S1: cleaning process; 1.1: Place the parts made by powder metallurgy under the fan for blowing to remove some impurities attached to the surface; 1.2: After purging, the parts are placed in the cleaning tank of the cleaning machine for cleaning, but there are no oil-absorbing cotton and magnetic bars in the cleaning tank; 1.3: No new water was added during cleaning, the cleaning time lasted for 10 minutes, and the water temperature during cleaning was controlled at 50°C; S2: Drying process: 2.1: Take the cleaned parts out of the cleaning machine and wipe the surface of the parts dry with a cloth that has water absorption capacity so that it no longer drips; 2.2: The wiped parts are placed in the drying section for further drying. During drying, hot air at 65°C is blown to the surface of the workpiece for 8 minutes to reduce the moisture content of the parts. The drying section is not independently set, and compared with embodiments 1, 2, 3, and 4, the drying section is shorter; S3: oil immersion process; 3.1: Use traditional anti-rust oil; 3.2: Heat the anti-rust oil to 110°C, then soak the dried parts in the anti-rust oil for 60 minutes; 3.3: After soaking, take the parts out of the anti-rust oil and drain the anti-rust oil on the surface of the parts, then let the parts stand at room temperature to cool for 25 minutes; 3.4: Randomly select multiple samples from the cooled parts and subject them to damp heat test and salt spray test. The damp heat test is to place the parts in a damp heat environment of 50°C for 4 hours. If all samples are not rusted after the test, it means that the batch of parts is qualified. If rust occurs, it is unqualified. S4: Full appearance inspection; 4.1: Place the parts after the oil immersion process in an open turntable for appearance inspection. The full inspection area is open. On-site personnel are able to directly contact the parts with or without protective measures. After the full appearance inspection is qualified, all rust prevention treatment of the parts can be completed.
[0020] 20 parts each treated by Examples 1, 2, 3, 4 and 5 were selected, for a total of 100 parts. The methods of Examples 1, 2, 3 and 4 are roughly the same, and only differ in some temperatures and treatment times. The treatment method of Example 5 is close to the traditional treatment method in the prior art. Therefore, Example 5 is used as a control group, and 100 parts selected are subjected to a second, more rigorous test. The test standards are as follows: These parts are uniformly placed in a closed space, and then a 0.5% NaCL solution is atomized and sprayed on the surface of the parts, and the temperature in the closed space is heated to 60°C for 1 hour, and then the number of parts corresponding to each embodiment that have rusted is checked. Then the test state is continued, and finally the time required for all 20 parts corresponding to the embodiment to rust is calculated. Through comparison, it is found that the present invention can effectively improve the rust prevention effect of powder metallurgy parts by improving the rust prevention method by arranging oil-absorbing cotton and magnetic bars and adopting a new rust-proof oil with better oil-water separation and dehydration properties.
[0021] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that, for those skilled in the art, the described embodiments can be modified in various ways without departing from the spirit and scope of the present invention. Therefore, the above description is illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.
Claims
1. A method for rust prevention of powder metallurgy parts, characterized in that: The specific steps are as follows: S1: cleaning process; 1.1: Place the parts made by powder metallurgy under the fan for blowing to remove some impurities attached to the surface; 1.2: After purging, the parts are placed in the cleaning tank of the cleaning machine for cleaning, and each cleaning tank is equipped with oil-absorbing cotton and magnetic rods; 1.3: New water is continuously added to the cleaning tank during cleaning, the cleaning time lasts for 5-12 minutes, and the water temperature during cleaning is controlled at 30-60℃; S2: Drying process: 2.1: Take the cleaned parts out of the cleaning machine and wipe the surface of the parts dry with a cloth that has water absorption capacity so that it no longer drips; 2.2: The wiped parts are placed in the drying section for further drying. During drying, hot air at 50-70°C is blown to the surface of the workpiece for 3-10 minutes to reduce the moisture content of the parts. S3: oil immersion process; 3.1: Use anti-rust oil, the raw materials of which include 100 parts of synthetic oil, 30 parts of rust inhibitor, 10 parts of diaryl secondary amine, 10 parts of organic acid salt, 5 parts of chemical demulsifier and 5 parts of anhydrous calcium chloride by weight; 3.2: Heat the anti-rust oil to 80-120℃, then immerse the dried parts in the anti-rust oil for 40-70 minutes; 3.3: After soaking, take the parts out of the anti-rust oil and drain the anti-rust oil on the surface of the parts, then let the parts stand at room temperature to cool for 15-30 minutes; 3.4: Rust detection; S4: Full appearance inspection; 4.1: Place the parts after the oil immersion process on a turntable with a protective cover and inspect their appearance.
2. A method for rust prevention of powder metallurgy parts according to claim 1, characterized in that: The cleaning machine in S1 is equipped with four cleaning tanks. The water in tank 4 is automatically discharged to tank 3 through the liquid level sensor and the water pump, ensuring that the water in tank 3 is clean and new water is continuously added.
3. A method for rust prevention of powder metallurgy parts according to claim 1, characterized in that: The drying section in S2 is separate and longer than the conventional drying section.
4. A method for rust prevention of powder metallurgy parts according to claim 1, characterized in that: The anti-rust oil in S3 should be kept flowing during the soaking process of the parts, and the mixed water-based liquid in the anti-rust oil should be removed regularly. At the same time, the anti-rust oil needs to be replenished and replaced regularly. During the soaking process of the parts, cooling water should be used to cool the anti-rust oil to ensure that the temperature of the anti-rust oil is within the set range. The filter bag for filtering the anti-rust oil needs to be replaced once a day. Only the sample needs to be processed in 3.4 in S3, and other parts do not need to be tested. However, it is necessary to wait for the results of the sample test. Only after passing the test can S4 be carried out.
5. The method for rust prevention of powder metallurgy parts according to claim 1, characterized in that: The rust detection is to randomly select multiple samples from the cooled parts, and subject the samples to wet heat test and salt spray test. If all samples are free of rust after the two tests, it means that the batch of parts is qualified. If rust occurs, it is unqualified. The wet heat test is to place the parts in a wet heat environment of 50°C for 4 hours, and the salt spray test is to spray a 0.5% NaCL solution on the parts after atomization for 30 minutes; Parts samples that have passed two tests must go through S1, S2, and S3 again even if they are qualified.
6. A method for rust prevention of powder metallurgy parts according to claim 1, characterized in that: The protective cover in S4 needs to be wiped every two hours. In addition, the full inspection area is in a closed state, the humidity in the full inspection area is controlled at 30-50%, and the temperature is maintained at 15-25℃. On-site personnel are equipped with sweat-proof sleeves, gloves and masks. After the full appearance inspection is passed, all anti-rust treatment of the parts can be completed.