A method for purifying the cladding of powder superalloys

Abstract

This invention relates to the field of powder metallurgy technology, and in particular to a method for purifying the cladding of powder metallurgy alloys. The process flow of this invention is as follows: high-pressure pre-cleaning, pre-vibration to remove impurities, high-pressure pure water cleaning, microscopic inspection, negative pressure drying, and oven drying. This invention uses pre-cleaning and pre-vibration combined with high-pressure water cleaning to efficiently complete the cladding purification process. It also includes a quantitative inspection method to ensure the effectiveness of the cladding purification process. Furthermore, the use of high-pressure water replaces the use of hazardous chemicals such as alcohol, reducing safety hazard management risks. The combination of negative pressure drying and oven drying improves drying efficiency. This invention is highly efficient, provides excellent purification results, and is suitable for replacing hazardous chemical control in the treatment of powder metallurgy cladding, where high purity and processing speed requirements are specified.

Description

Technical Field

[0001] This invention relates to the field of powder superalloy technology, and in particular to a method for purifying powder superalloys using a cladding process. Background Technology

[0002] As a key component of high-performance aero-engines, powder metallurgy superalloy parts endure the combined effects of high temperature and high stress, operating under extremely harsh conditions. The process is lengthy, complex, and technically challenging. Existing powder metallurgy superalloy parts exhibit three main defects: inclusions, original particle boundaries, and thermally induced porosity. Inclusions are the most significant defect affecting the yield rate, accounting for over 90% of scrapped parts. Therefore, successful purity control directly determines whether the quality of powder metallurgy superalloy parts meets the requirements of aero-engines, making it extremely important. In the preparation of powder metallurgy superalloy parts for aero-engines, hot isostatic pressing (HIP) is an essential processing step. To ensure the smooth execution of HIP, the powder is typically encapsulated in a welded, small-aperture cylindrical sheath. To minimize the introduction of inclusions and ensure the purity of powder metallurgy superalloy parts during mass production, strict anti-contamination measures are required at each stage of the process. After welding, the casing contains foreign impurities such as weld slag, dust, and oil, which are difficult to remove. The casing needs purification treatment before powder filling to guarantee the purity of the subsequent powder metallurgy superalloy parts. Currently, casing purification is often neglected. Even when cleaning is done, it mainly involves alternating between tap water, alcohol, or gasoline, using mechanical or manual methods to continuously turn the casing over. This purification process is ineffective, requires numerous cleaning cycles, and has inconsistent cleaning results, making it impossible to quantitatively determine the cleaning effect. This can easily introduce external inclusions into the subsequent powder filling process, leading to the scrapping of powder metallurgy superalloy parts. Furthermore, the use of hazardous chemicals poses significant safety hazards. The drying process after cleaning mainly relies on natural air drying and oven drying, consuming up to 24 hours, which is detrimental to the efficiency requirements of mass production.

[0003] This invention provides a purification process for the cladding of powder superalloys. The resulting cladding completely avoids contamination from welding slag, dust, and oil, effectively improving the purity and qualification rate of the finished product after powder filling of powder superalloy parts. It also avoids the use of hazardous chemicals, greatly shortens the processing cycle, and saves costs. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention provides a packaging purification method that has good purification effect, high efficiency, does not rely on hazardous chemicals, and can be dried quickly.

[0005] The technical solution adopted in this invention is: a method for purifying the cladding of powder superalloys, the process flow of which is as follows:

[0006] (1) High-pressure pre-cleaning

[0007] Before welding, the cladding assembly is placed in a liquid high-pressure cleaning chamber and pre-cleaned with cleaning fluid. After cleaning, it is rinsed twice with high-pressure pure water.

[0008] (2) Pre-vibration to remove impurities

[0009] The welded sleeve is placed on a hydraulic vibration device for vibration.

[0010] (3) High-pressure water cleaning

[0011] After vibration, place the sleeve upside down on the turntable of the cleaning device. Insert the high-pressure pure water cleaning bidirectional nozzle into the inner cavity of the sleeve, adjusting the insertion height according to the height of the sleeve. Clean with high-pressure pure water at a pressure of 10-30MPa. The horizontal rotation speed of the sleeve is 8-20r / min, and the nozzle lifting speed is 4-15mm / s. After cleaning, clean the sleeve with high-pressure pure water at a pressure of 20-50MPa a second time, keeping the nozzle lifting speed and turntable speed unchanged. Drain until no pure water is visible to the naked eye flowing out.

[0012] (4) Microscopic examination

[0013] The water after the second high-pressure water cleaning is collected using an inspection device equipped with a 200-500 mesh stainless steel screen. It is then placed under an optical microscope and magnified to 300-500 times. If there are no more than 10 impurities, it is considered qualified. Otherwise, the water is cleaned again according to the second high-pressure water cleaning process.

[0014] (5) Negative pressure control

[0015] Place the package, which has been cleaned with high-pressure pure water, upside down on the tooling rack, connect the package opening to the negative pressure drying device, and pump to below 500Pa for 10-30 minutes.

[0016] (6) Oven drying

[0017] Place the negative pressure drying bag with an 80-200 mesh stainless steel screen over its opening and place it upright in an oven. Heat it to 100-150℃ and dry it for 30-90 minutes to obtain a qualified cleaning bag.

[0018] The high-pressure pre-cleaning cleaning fluid comprises the following raw materials in parts by volume:

[0019] AHC-1 type water-based cleaning agent: purified water = 1:(7-9).

[0020] The preparation method of the high-pressure pre-cleaning cleaning solution is as follows: using pure water as the base, add AHC-1 type water-based cleaning agent while continuously stirring, and stir evenly.

[0021] The pre-cleaning of the cleaning fluid in step (1) is carried out at a pressure of 10-30 MPa.

[0022] The step (1) involves cleaning with high-pressure pure water at a pressure of 10-30 MPa.

[0023] In step (2), the hydraulic vibration device vibrates at a frequency of 15-30 Hz and a displacement of 1-2 mm for 5-10 minutes.

[0024] The stainless steel screen must be manufactured using laser cutting technology.

[0025] The aforementioned powder high-temperature alloy cladding purification process involves using a stainless steel screen with a power of 200-500W and a cutting speed of 20-50mm / s during laser cutting.

[0026] Compared with the prior art, the beneficial effects of the present invention are: the purification treatment of the packaging is completed in a highly efficient manner by using pre-cleaning, pre-vibration and high-pressure water cleaning, and a quantitative testing method is invented to ensure the effect of packaging purification treatment. At the same time, the use of high-pressure water replaces the use of hazardous chemicals such as alcohol, reducing the risk of safety hazard management, and the combination of negative pressure drying and oven drying improves the drying efficiency. Detailed Implementation

[0027] The present invention will be further described below with reference to embodiments. The following description is by way of example, but the scope of protection of the present invention should not be limited thereto.

[0028] A method for purifying a cladding for powder superalloys, the process of which is as follows:

[0029] (1) High-pressure pre-cleaning

[0030] The cladding assembly, before welding, is placed in a high-pressure liquid cleaning chamber. It is pre-cleaned with a cleaning solution, followed by two rinses with high-pressure purified water. The pre-cleaning with the cleaning solution is performed at a pressure of 10-30 MPa, and the rinsing with high-pressure purified water is also performed at a pressure of 10-30 MPa. The high-pressure pre-cleaning solution comprises the following components by volume: AHC-1 type water-based cleaning agent: purified water = 1:(7-9). The high-pressure pre-cleaning solution is prepared as follows: using purified water as a base, AHC-1 type water-based cleaning agent is added while continuously stirring until homogeneous.

[0031] (2) Pre-vibration to remove impurities

[0032] Place the welded sleeve on a hydraulic vibration device for vibration; the hydraulic vibration device uses a frequency of 15-30HZ and a displacement of 1-2mm for vibration for 5-10 minutes.

[0033] (3) High-pressure water cleaning

[0034] After vibration, place the sleeve upside down on the turntable of the cleaning device. Insert the high-pressure pure water cleaning bidirectional nozzle into the inner cavity of the sleeve, adjusting the insertion height according to the height of the sleeve. Clean with high-pressure pure water at a pressure of 10-30MPa. The horizontal rotation speed of the sleeve is 8-20r / min, and the nozzle lifting speed is 4-15mm / s. After cleaning, clean the sleeve with high-pressure pure water at a pressure of 20-50MPa a second time, keeping the nozzle lifting speed and turntable speed unchanged. Drain until no pure water is visible to the naked eye flowing out.

[0035] (4) Microscopic examination

[0036] The water after the second high-pressure water cleaning is collected using an inspection device equipped with a 200-500 mesh stainless steel screen. It is then placed under an optical microscope and magnified to 300-500 times. If there are no more than 10 impurities, it is considered qualified. Otherwise, the water is cleaned again according to the second high-pressure water cleaning process.

[0037] (5) Negative pressure control

[0038] Place the package, which has been cleaned with high-pressure pure water, upside down on the tooling rack, connect the package opening to the negative pressure drying device, and pump to below 500Pa for 10-30 minutes.

[0039] (6) Oven drying

[0040] Place the negative pressure drying bag with an 80-200 mesh stainless steel screen over its opening and place it upright in an oven. Heat to 100-150℃ and dry for 30-90 minutes to obtain a qualified cleaning bag. The stainless steel screen must be manufactured using laser cutting technology.

[0041] The purification process for the cladding of powder high-temperature alloys involves using a stainless steel screen with a laser cutting power of 200-500W and a cutting speed of 20-50mm / s. Compared with existing technologies, the advantages of this invention are that it efficiently completes the purification process of the cladding by using pre-cleaning, pre-vibration, and high-pressure water cleaning. It also includes a quantitative testing method to ensure the effectiveness of the purification process. Furthermore, the use of high-pressure water replaces the use of hazardous chemicals such as alcohol, reducing safety risks. The combination of negative pressure drying and oven drying further improves drying efficiency.

[0042] Example 1:

[0043] The specific process flow of the purification treatment method for the cladding of powder superalloys in this embodiment is as follows:

[0044] (1) High-pressure pre-cleaning:

[0045] First, the cleaning solution is prepared using a ratio of AHC-1 water-based cleaning agent to purified water of 1:9, with purified water as the base. AHC-1 water-based cleaning agent is added while continuously stirring. After thorough mixing, the cleaning solution is added to the high-pressure cleaning equipment. The pre-welding cladding assemblies with diameters of 200-600mm are placed in the liquid high-pressure cleaning chamber and pre-cleaned using a pressure of 15MPa. After cleaning, the cladding assemblies are cleaned twice with high-pressure purified water at a pressure of 15MPa.

[0046] (2) Pre-vibration to remove impurities:

[0047] The welded sleeve was placed on a hydraulic vibration device and vibrated at a frequency of 15 Hz and a displacement of 1.5 mm for 5 minutes.

[0048] (3) High-pressure water cleaning:

[0049] After vibration, the sleeve is placed upside down on the turntable of the cleaning device. The high-pressure pure water cleaning bidirectional nozzle is inserted into the inner cavity of the sleeve. The insertion height is adjusted according to the height of the sleeve. High-pressure pure water at a pressure of 20MPa is used for cleaning. The horizontal rotation speed of the sleeve is 12r / min, and the nozzle lifting speed is 15mm / s. After cleaning, the stainless steel sleeve that has undergone one high-pressure water cleaning is cleaned a second time with high-pressure pure water at a pressure of 30MPa. The nozzle lifting speed and the turntable speed remain unchanged. It is then drained until no pure water is visible to the naked eye.

[0050] (4) Microscopic examination:

[0051] The water after the second high-pressure water cleaning is collected using an inspection device equipped with a 500-mesh sieve and placed under an optical microscope at 500x magnification. If there are no more than 10 impurities, it is considered qualified; otherwise, it is cleaned again according to the second high-pressure water cleaning process.

[0052] (5) Negative pressure control:

[0053] The package that has been cleaned with high-pressure pure water is placed upside down on the tooling rack. The negative pressure drying device is connected to the package opening, and the pressure is drawn to below 500Pa for 10 minutes.

[0054] (6) Drying in an oven:

[0055] Place the negative pressure drying bag with an 80-mesh stainless steel screen over its opening and put it upright in the drying oven. Heat it to 100℃ and dry it for 30 minutes to make it a qualified cleaning bag.

[0056] Example 2:

[0057] The specific process flow of the purification treatment method for the cladding of powder superalloys in this embodiment is as follows:

[0058] (1) High-pressure pre-cleaning:

[0059] First, the cleaning solution is prepared using a ratio of AHC-1 water-based cleaning agent to purified water of 1:7, with purified water as the base. AHC-1 water-based cleaning agent is added while continuously stirring. After thorough mixing, the cleaning solution is added to the high-pressure cleaning equipment. The pre-welding cladding assemblies with a diameter of 600-1000mm are placed in the liquid high-pressure cleaning chamber and pre-cleaned using a pressure of 20MPa. After cleaning, the cladding assemblies are cleaned twice with high-pressure purified water at a pressure of 20MPa.

[0060] (2) Pre-vibration to remove impurities:

[0061] The welded sleeve was placed on a hydraulic vibration device and vibrated at a frequency of 26 Hz and a displacement of 1.8 mm for 10 minutes.

[0062] (3) High-pressure water cleaning:

[0063] After vibration, the sleeve is placed upside down on the turntable of the cleaning device. The high-pressure pure water cleaning bidirectional nozzle is inserted into the inner cavity of the sleeve. The insertion height is adjusted according to the height of the sleeve. High-pressure pure water at a pressure of 30MPa is used for cleaning. The horizontal rotation speed of the sleeve is 8r / min, and the nozzle lifting speed is 10mm / s. After cleaning, the stainless steel sleeve that has undergone one high-pressure water cleaning is cleaned a second time at a pressure of 45MPa. The nozzle lifting speed and the turntable speed remain unchanged. It is then drained until no pure water is visible to the naked eye.

[0064] (4) Microscopic examination:

[0065] The water after the second high-pressure water cleaning is collected using an inspection device equipped with a 500-mesh sieve and placed under an optical microscope at 300x magnification. If there are no more than 10 impurities, it is considered qualified; otherwise, it is cleaned again according to the second high-pressure water cleaning process.

[0066] (5) Negative pressure control:

[0067] The package that has been cleaned with high-pressure pure water is placed upside down on the tooling rack. The negative pressure drying device is connected to the package opening, and the pressure is drawn to below 500Pa for 30 minutes.

[0068] (6) Drying in an oven:

[0069] Place the negative pressure dried bag with an 80-mesh sieve over its opening and place it upright in an oven. Heat it to 100°C and dry it for 90 minutes to obtain a qualified cleaning bag.

Claims

1. A method for purifying powder metallurgy superalloys using a cladding process, characterized in that, The process is as follows: (1) High-pressure pre-cleaning Before welding, the cladding assembly is placed in a liquid high-pressure cleaning chamber and pre-cleaned with cleaning fluid. After cleaning, it is rinsed twice with high-pressure pure water. (2) Pre-vibration to remove impurities The welded sleeve is placed on a hydraulic vibration device for vibration. (3) High-pressure water cleaning After vibration, place the sleeve upside down on the turntable of the cleaning device. Insert the high-pressure pure water cleaning bidirectional nozzle into the inner cavity of the sleeve, adjusting the insertion height according to the height of the sleeve. Clean with high-pressure pure water at a pressure of 10-30MPa. The horizontal rotation speed of the sleeve is 8-20r / min, and the nozzle lifting speed is 4-15mm / s. After cleaning, clean the sleeve with high-pressure pure water at a pressure of 20-50MPa a second time, keeping the nozzle lifting speed and turntable speed unchanged. Drain until no pure water is visible to the naked eye flowing out. (4) Microscopic examination The water after the second high-pressure water cleaning is collected using an inspection device equipped with a 200-500 mesh stainless steel screen. It is then placed under an optical microscope and magnified to 300-500 times. If there are no more than 10 impurities, it is considered qualified. Otherwise, the water is cleaned again according to the second high-pressure water cleaning process. (5) Negative pressure control Place the package, which has been cleaned with high-pressure pure water, upside down on the tooling rack, connect the package opening to the negative pressure drying device, and pump to below 500Pa for 10-30 minutes. (6) Oven drying Place the negative pressure drying bag with an 80-200 mesh stainless steel screen over its opening and place it upright in an oven. Heat it to 100-150℃ and dry it for 30-90 minutes to obtain a qualified cleaning bag.

2. The method for purifying the cladding of powder superalloys according to claim 1, characterized in that, The high-pressure pre-cleaning cleaning fluid comprises the following raw materials in parts by volume: AHC-1 type water-based cleaning agent: purified water = 1: (7-9).

3. The method for purifying the cladding of powder superalloys according to claim 1, characterized in that, The preparation method of the high-pressure pre-cleaning cleaning solution is as follows: using pure water as the base, add AHC-1 type water-based cleaning agent while continuously stirring, and stir evenly.

4. The method for purifying powder superalloys according to claim 1, characterized in that, The pre-cleaning with the cleaning fluid is performed at a pressure of 10-30 MPa.

5. The method for purifying the cladding of powder superalloys according to claim 1, characterized in that, The high-pressure pure water cleaning process uses a pressure of 10-30 MPa.

6. The method for purifying the cladding of powder superalloys according to claim 2, characterized in that, The hydraulic vibration device vibrates at a frequency of 15-30Hz and a displacement of 1-2mm for 5-10 minutes.

7. The method for purifying the cladding of powder superalloys according to claim 6, characterized in that, The stainless steel screen must be manufactured using laser cutting technology.

8. The method for purifying the cladding of powder superalloys according to claim 6, characterized in that, The stainless steel screen is laser-cut using a power of 200-500W and a cutting speed of 20-50mm / s.