Crack magnetic powder detection method based on temperature difference

Abstract

The invention belongs to the related technical field of ferromagnetic material nondestructive inspection, and discloses a crack magnetic powder detection method based on temperature difference, and the detection method comprises the following steps: firstly, in a magnetization field, magnetic powder having temperature difference with a tested piece is sprayed on the tested piece, and a thermogram of the tested piece is obtained in real time; then, the obtained thermogram is processed to obtain the temperature change of the tested piece, and then crack recognition is conducted on the tested piece according to the obtained temperature change result; and when a crack exists in the tested piece, a leakage magnetic field generated at the crack attracts the magnetic powder to gather so as to form a magnetic trace, the temperature at the magnetic trace is different from the temperature of other areas of the tested piece, and the difference between the temperature at the magnetic trace and the temperature of the tested piece is amplified due to the gathering of the magnetic powder. According to the method, information of crack magnetic traces is prevented from being affected when non-relevant magnetic traces are removed manually, common dry magnetic powder is used and is easy to remove and recycle, pollution to a test piece is low, and pollution to the environment is avoided.

Description

technical field [0001] The invention belongs to the related technical field of non-destructive testing of ferromagnetic materials, and more specifically relates to a crack magnetic particle testing method based on temperature difference. Background technique [0002] With the needs of social production and development, the demand for ferromagnetic components in various industrial fields has increased significantly, and there is an increasing demand for their surface quality. Non-destructive testing mainly includes five methods: ultrasonic testing, ray testing, eddy current testing, magnetic particle testing and penetrant testing. Among them, magnetic particle testing is an important non-destructive testing technology with a large amount and a wide range. More than 70% of aviation, aerospace, military, Steel components in the railway and petroleum industries, and more than 80% of automotive steel safety parts require magnetic particle inspection. [0003] According to the co...

AI Technical Summary

Problems solved by technology

Some human-assisted operations in traditional magnetic particle testing are difficult to carry out. How to ensure the accuracy of magnetic particle testing and replace cumbersome manual operations is a difficult problem that needs to be solved in the development of magnetic particle testing automation.

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