A device for calibration of tension and compression residual stress

Abstract

The invention discloses a device for calibrating tension and compression type residual stress, and belongs to the technical field of experimental stress measurement in a process of material processing. The device comprises a tension and compression loading mechanism, a clamping mechanism and a supporting mechanism. The tension and compression loading mechanism applies uniform tensile or compressive stress in all the thickness directions of a calibration material; the clamping mechanism can adjust a clamping position according to the tension and compression type of the calibration material; the supporting mechanism is provided with the tension and compression loading mechanism and the clamping mechanism, and can automatically adjust the height. The device can be used as a matched loading device for a blind hole method, an indentation strain method and other residual stress detection methods, and accurately calibrates the material stress-strain relationship in a tensile stress state and in a compressive stress state; besides, the device is simple and flexible to operate and convenient to use, and overcomes the problems that a device is convenient and easy to use but a stress field is nonuniform during three-point bending loading, or the problems that large-size samples are required and loading is not easy during calibration with a tensile test machine.

Description

technical field [0001] The invention relates to the technical field of experimental stress measurement during material processing, in particular to a tension-compression type residual stress calibration device, which can calibrate the stress-strain relationship of materials in a tension stress state or a compression stress state. Background technique [0002] Cold and hot processing technologies such as welding, casting and plastic forming have been widely used in various civil and military fields, and play an extremely important role in the development of the national economy and national defense. Uneven heating and cooling during thermal processing will cause considerable residual stress in the component, and the residual stress will have different effects on the mechanical properties of the component, especially reducing the fatigue performance and stress corrosion performance of the component. The uneven deformation of the material during the cold working process causes ...

AI Technical Summary

Problems solved by technology

One-way loading has higher accuracy due to the absence of stress unevenness in the thickness direction, but ordinary tensile or compression testing machines are mostly vertical mechanisms, which has a lot of inconvenience for the calibration process of materials

If a larger sample size is required, and it is easy to bend and lose stability when compressed

Although the loading method of three-point bending is very flexible, the uniform stress area is narrow and the required material size is also large

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