CN-121977898-A - Machining and corrosion method for high-temperature alloy low-power inspection

Abstract

The invention belongs to the technical field of low-power processing and defect identification of high-temperature alloy, and in particular relates to a processing and corrosion method for low-power inspection of the high-temperature alloy, which comprises the following steps of S1, polishing the outer surface of a finished bar of the high-temperature alloy after forging/rolling forming, removing surface oxide skin and cracks, sawing a sample piece, and then carrying out standard heat treatment on the sample piece to remove stress so as to reduce the stress before processing and obtain a low-power sample; and S2, turning the low-power sample on a lathe according to specific technological parameters until the surface roughness Ra is less than or equal to 1.0 mu m, and S3, spraying a cleaning solution on the surface of the turned low-power sample to remove greasy dirt, drying the surface, putting the surface in special corrosion equipment for corrosion by adopting a corrosive liquid, and flushing and drying the surface after the corrosion is finished. The method improves the processing and corrosion quality of the low-power sample for detecting the superalloy, shortens the production period and saves the cost.

Inventors

• KAN ZHI
• WANG FAN
• Mu Xiuxin
• WANG XUPENG
• Kang Mengke
• CAO GUOXIN
• HE YONGSHENG
• FU BAOQUAN

Assignees

• 西安聚能高温合金材料科技有限公司

Dates

Publication Date

20260505

Application Date

20251230

Claims (8)

1. 1. A method of machining and etching for low-pass inspection of superalloy, comprising the steps of: S1, after forging/rolling forming of a high-temperature alloy finished bar, polishing the outer surface, sawing a sample piece, and then carrying out standard heat treatment on the sample piece to obtain a low-power sample; s2, turning the low-power sample on a lathe according to specific technological parameters until the surface roughness Ra is less than or equal to 1.0 mu m; and S3, spraying cleaning liquid on the surface of the turned low-power sample to remove greasy dirt, drying the surface, putting the surface into special corrosion equipment to carry out corrosion by adopting corrosion liquid, and washing and drying the surface after the corrosion is finished.
2. 2. The processing and corrosion method according to claim 1, wherein in S1, the specification of the high-temperature alloy finished bar is phi 30-phi 800mm, and the sawing process of the sample wafer is as follows: When the specification of the high-temperature alloy finished bar is smaller than phi 500mm, sawing into a sample piece with the thickness of 15-25 mm; when the specification of the high-temperature alloy finished bar is larger than or equal to phi 500mm, sawing a middle slice with the thickness of 15-25 mm, detecting the cutting angle and the maximum thickness of the middle slice, and if the cutting angle is larger than 3mm and the maximum thickness is smaller than 10mm, equally dividing the middle slice by adopting a sawing machine or wire cutting, so as to obtain a sample piece.
3. 3. The method of claim 1, wherein in S1, the standard heat treatment is performed for a time period greater than or equal to 0.1D min and less than 0.5D min, wherein D is the diameter of the finished superalloy rod.
4. 4. The method of claim 1, wherein in S2, lathe turning is performed in two passes, rough turning and then finish turning; Each pass is processed according to the following specific technological parameters, namely the rotating speed of a main shaft is 20-160 r/min, the transverse feeding speed of a cutter is 0.05-0.2 mm/r, and the longitudinal feeding speed of the cutter is 0.01-0.15 mm/r.
5. 5. The method according to claim 1, wherein in S3, the cleaning liquid is selected from alcohol, water-based cleaning agent, and alcohol-based cleaning agent.
6. 6. The processing and corrosion method according to claim 1, wherein in S3, the special corrosion equipment is a corrosion pickling machine, the spraying flow is set to 20-40 l/h during corrosion, the spraying mode is rotary, the rotation speed is 1-20 r/min, the spraying time is 12-25 min, and the spraying diameter of a single spray head is 100-500 mm.
7. 7. The method according to claim 1, wherein in S3, the etching solution comprises ferric chloride, hydrochloric acid and water in a volume ratio of 2-5:0.5-3:1.
8. 8. The method of claim 1, wherein in S3, the etching is completed with an ammonium sulfate solution.

Description

Machining and corrosion method for high-temperature alloy low-power inspection Technical Field The invention belongs to the technical field of low-power processing and defect identification of high-temperature alloy, and particularly relates to a processing and corrosion method for low-power inspection of high-temperature alloy. Background High-temperature alloys (such as nickel-based, cobalt-based and iron-nickel-based alloys) are widely applied to hot end components in the key fields of aeroengines, gas turbines, nuclear power and the like due to the excellent high-temperature strength, oxidation resistance and creep resistance. The internal metallurgical quality of the finished bar material, which is used as a raw material for preparing the core components, directly determines the performance and service safety of the final product. The macroscopic structure inspection is a core means for evaluating the internal quality of the bar, can effectively display macroscopic defects such as shrinkage cavity, looseness, cracks, inclusions, segregation, grain uniformity and the like, and is an indispensable link for controlling the quality of materials and the production process. Currently, low-power inspection of superalloy finished rods typically involves sampling, machining (grinding or milling to prepare the viewing surface), etching, cleaning, viewing, and the like. However, superalloys are subject to particular challenges due to their extremely high degree of alloying, dense structure, and the tendency of the surface to form stable passivation films (e.g., chromium-rich oxide layers), resulting in the display of their low-order structure. The existing processes such as machining and corrosion have the following defects: In the processing stage, if a conventional grinding or milling process is adopted, a deeper deformation layer or heat affected zone is easily introduced on the surface of the sample. The processing damage layer can mask the true macroscopic tissue of the material, false marks can be generated in subsequent corrosion, or corrosion unevenness can be caused, so that the accuracy and reliability of defect interpretation are affected, and when the diameter reaches more than 500mm, the traditional sampling mode is time-consuming and cost-consuming. In the corrosion stage, the conventional corrosion method (such as an acid corrosion method for common structural steel) is difficult to effectively and clearly display the actual macroscopic grain morphology and internal defects; The common corrosive agents (such as ammonium persulfate, hydrochloric acid and hydrogen peroxide mixed solution and the like) have low pertinence to the high-temperature alloy. The corrosion rate can be difficult to control, when the corrosion is insufficient, the grain boundary and the defect outline are fuzzy, the structure is incomplete, and when the corrosion is excessive, the grain boundary is too wide, details are lost, even corrosion products are accumulated, and the shape of the real structure is polluted. Especially for high-temperature alloys with different batches or different components, the process stability is poor and the reproducibility is poor. In view of the foregoing, there is a need in the art to develop a process for integrating low-power machining and corrosion for superalloy finished bars. Disclosure of Invention The invention aims to overcome the defects of the prior art, and provides a processing and corrosion method for the low-power inspection of a high-temperature alloy, which can effectively remove or reduce a processing damage layer, realize clear, real and uniform display of macroscopic tissues through an optimized corrosion formula and process parameters and has excellent process stability and reproducibility, thereby providing more reliable technical guarantee for quality evaluation of the high-temperature alloy bar. In order to achieve the above purpose, the present invention adopts the following technical scheme: the invention provides a processing and corrosion method for high-temperature alloy low-power inspection, which comprises the following steps: S1, polishing the outer surface of a high-temperature alloy finished bar after forging/rolling forming, removing surface oxide skin and cracks, sawing a sample piece, and then carrying out standard heat treatment on the sample piece to remove stress so as to reduce the stress before processing and obtain a low-power sample; s2, turning the low-power sample on a lathe according to specific technological parameters until the surface roughness Ra is less than or equal to 1.0 mu m; And S3, spraying cleaning liquid on the surface of the turned low-power sample to remove greasy dirt, drying the surface, putting the surface into special corrosion equipment to carry out corrosion by adopting corrosion liquid, and washing and drying the surface after the corrosion is finished. The etching may be performed simultaneously on a plurality of low power samp