Universal fixture for compression creep aging and stress relaxation aging experiments of round bar-shaped sample

Abstract

The invention discloses a universal fixture for compression creep aging and stress relaxation aging experiments of a round bar-shaped sample. The fixture comprises a fixture body, a conductive deviceand a plurality of locking devices, the fixture body comprises two clamping parts, each clamping part is provided with an inner groove, and the inner grooves of the two clamping parts define a clamping through hole used for containing a round-rod-shaped sample; the conductive device comprises two conductive blocks which are connected with the two clamping parts respectively; when in use, the clampis clamped in the middle of a test sample to protect the test sample; according to the universal fixture, the compression creep aging / stress relaxation aging experiment with the initial loading stress higher than the yield strength of the material can be accurately tested; meanwhile, a compression experiment can be carried out at high temperature, the reliability of creep aging / stress relaxationaging experiment data is guaranteed, and the sample is not bent after aging is finished. The universal fixture is simple in structure, convenient to use and wide in application range.

Description

technical field [0001] The invention relates to the technical field of auxiliary experimental equipment, in particular to a universal fixture for compression creep aging and stress relaxation aging experiments of round rod samples. Background technique [0002] With the increasing demand of advanced aerospace vehicles for structures such as high strength, light weight, long life and high temperature resistance. Commonly used complex component forming methods mainly include: bending forming, shot peening forming, creep aging forming, laser sheet metal forming, spinning and stamping, etc. Time-dependent stress relaxation is an ideal method for forming aging aluminum alloy large-scale wing panels. The residual stress of the panel after forming is small, less fixtures are needed during the forming process, the forming process is repeatable, and the fatigue resistance performance is significantly improved. Time-effect stress relaxation forming is a process method that uses the s...

AI Technical Summary

Problems solved by technology

At present, there have been many studies on the stress relaxation aging test fixture of uniaxial tension, but the compressive stress relaxation test fixture of aluminum alloy rods is currently limited to the initial loading stress in the elastic stage, when the stress exceeds the initial stress of the elastic stage cause the material to buckle

Compressive stress relaxation is different from stretching. Cylindrical aluminum alloy rod samples are subjected to compressive stress relaxation aging experiments on a creep machine (at high temperature) for more than 16 hours. The material is often softened in the initial aging stage due to high temperature. When the loaded force exceeds Its own yield strength, the cylindrical aluminum alloy rod sample will produce bending instability, which will cause the distortion of the stress relaxation experiment data, and it is impossible to test the correct relaxation curve of the high temperature stress relaxation aging experiment under the yield strength

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