Cold pickling solution for identifying surface defects of high-nitrogen stainless steel and application of cold pickling solution

Abstract

The invention relates to a cold pickling solution for identifying surface defects of high-nitrogen stainless steel and application of the cold pickling solution, and belongs to the technical field of alloy surface defect identification. The cold pickling solution for identifying the surface defects of the high-nitrogen stainless steel is prepared from the following components in percentage by mass: 2.1 to 4.3 percent of HCl, 19.5 to 25.5 percent of H3PO4, 8 to 17 percent of FeCl3 and the balance of water. According to the formula of the cold pickling solution, the surface of high-nitrogen stainless steel can be quickly corroded, the corrosion time is only 1-2 min, the pickling amount after corrosion is 2 microns or below, excessive damage to the surface quality of parts is avoided, the identification accuracy rate of the grinding burn defects of the surface of the high-nitrogen stainless steel bearing reaches 100%, and in addition, long-term stable storage of the cold pickling solution can be guaranteed; and the effective service life is more than three months.

Description

technical field [0001] The invention belongs to the technical field of alloy surface defect identification, in particular to a cold pickling solution for identifying surface defects of high nitrogen stainless steel and its application. Background technique [0002] Grinding burn is that the instantaneous high temperature during grinding changes the local metallographic structure of the surface layer of the part, which will reduce the hardness of the part and produce small cracks and other defects, which seriously damage the quality of the parts. In order to identify whether the surface of the part has grinding burn defects, chemical cold pickling technology is a simple, intuitive, high-accuracy and low-cost method. Chemical cold pickling is to corrode the surface of parts with acid. Since different metallographic structures have different sensitivities to acid corrosion, the color difference presented by different degrees of surface corrosion is used to judge grinding burn d...

AI Technical Summary

Problems solved by technology

Although the pickling solution of this formula can detect the surface defects of high-nitrogen corrosion-resistant steel, it is found that its effective use frequency is extremely low in actual application, and a large amount of pickling solution needs to be continuously prepared for batch testing, and the cost is relatively high. high

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