Determination method of deep residual stress

Abstract

The method for measuring the deep residual stress comprises the following steps of: 1, determining a detection area on a workpiece to be measured, and setting the detection area as an area to be measured; 2, carrying out metal cutting sampling on the to-be-detected area; step 3, carrying out electrolytic corrosion on the cut sampling part on the basis of the step 2; 4, residual stress measurement is carried out on the to-be-measured area and the to-be-measured direction of the cut sampling part, measurement results are obtained, and meanwhile measurement data results are summarized and analyzed; wherein the metal cutting mode adopted in the second step is low-speed wire cutting. According to the method, the required measuring depth can be achieved, and the residual stress of the to-be-measured part of the part in the to-be-measured direction is not greatly released.

Description

technical field [0001] The invention relates to the field of measuring parts, in particular to a method for measuring deep residual stress. Background technique [0002] Residual stress is an important factor affecting the service life of parts. The failure of parts is mostly due to the fact that the sum of residual stress and working stress inside the part is greater than the strength. [0003] Shot peening is a surface strengthening process widely used in factories. By bombarding the surface of the workpiece with pellets and implanting residual compressive stress, it is a cold working process to improve the fatigue strength of the workpiece. Shot peening can improve the residual compressive stress, but the depth of the compressive stress layer after shot peening is shallower than that of the hardened layer, and the depth of the hardened layer, which is closely related to the fatigue performance of the parts, is 10% of the depth of the residual compressive stress layer afte...

AI Technical Summary

Problems solved by technology

[0004] Existing residual stress measurement methods are mainly profile method and diffraction method. In industrial production, the surface residual stress is mainly measured by X-ray diffractometer; the depth of electrolytic corrosion can be realized at millimeter level, and the release of residual stress caused by Small, the subsurface layer can be measured after peeling off the layer by chemical peeling method; but due to the slow speed of chemical corrosion and limited corrosion depth, it is difficult to measure the distribution of deeper residual stress field

Newer neutron diffraction systems can measure residual stress down to a few centimeters, but have not been widely used due to expensive and scarce equipment

An economical and practical deep residual stress measurement method is a difficult point in residual stress related research, and there is no relevant data to describe a feasible measurement method for production.

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