Steel spring surface full-decarburization nondestructive testing method

Abstract

The invention relates to a steel spring surface full-decarburization nondestructive testing method. The method comprises the steps of selecting a spring sampling position; pretreating the surface to be tested of the sampling position; polishing the surface to be tested so that the base metal surface can be exposed; cleaning the exposed base metal surface with a solvent which is not corrosive to the metal surface and does not react with metal chemically; corroding the base metal surface; coating the base metal surface; conducting testing and observation, and evaluating the full-decarburization condition by means of a reference atlas. According to the method, on the premise that the structure of a spring is not damaged and later-stage use of the spring is not affected, the metallographic phase of the surface of the spring is copied and observed so that the surface full-decarburization condition can be learnt, spring quality is efficiently controlled, and the spring hot working process is improved.

Description

technical field [0001] The invention relates to a non-destructive detection method for full decarburization on the surface of a steel spring, belonging to the technical field of metal non-destructive detection. Background technique [0002] The surface decarburization of the spring affects the quality of the spring, especially the full decarburization of the surface will greatly reduce the fatigue life of the spring. [0003] At present, there are mainly metallographic methods and Leeb hardness methods for the full decarburization inspection of the spring surface. The metallographic method requires the spring to be cut and inspected, which destroys the structure of the spring and makes the inspected spring unusable, thus increasing the cost of the test and inspection; since the surface of the steel spring is a curved surface, the surface hardness of the spring using the Leeb hardness tester is relatively large. The error cannot accurately reflect the real hardness value, so...

AI Technical Summary

Problems solved by technology

The metallographic method requires the spring to be cut and inspected, which destroys the structure of the spring and makes the inspected spring unusable, thus increasing the cost of the test and inspection; since the surface of the steel spring is a curved surface, the surface hardness of the spring using the Leeb hardness tester is relatively large. The error cannot accurately reflect the real hardness value, so the Leeb hardness method cannot accurately detect the decarburization of the spring surface

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