Method for acquiring uniaxial stress-strain relation of materials by disc specimen compression

Abstract

The invention discloses a method for acquiring a uniaxial stress-strain relation of materials by disc specimen compression. The method includes processing a compression fixture by cemented carbide, compressing a disc specimen moderate in thickness to acquire a continuous load-displacement curve of a disc specimen, fitting a load-displacement curve (nonlinear segment) by a power law, and computing by putting fitted feature load and a displacement index into a formula (2) so as to acquire the uniaxial stress-strain relation. The method is applicable to ductile and power-law isotropic hardening materials and is capable of acquiring the stress-strain relation curves of multiple types of ductile materials, the specimen size can be designed according to actual conditions of testing materials, specimens can be minimized to millimeter size and micron size flexibly and conveniently, the shortcomings that traditional uniaxial tensile tests are limited by material size greatly and the like are overcome, and the high-temperature uniaxial stress-strain relation curves of the materials can be tested. The method has the great advantage on testing of constitutive relations of small specimens such as precious metals, light materials and existing structural member minimal-invasion discs.

Description

Technical field [0001] The present invention relates to the mechanical property testing technology of ductile materials, in particular to the mechanical property testing field of lightweight, rare and micro-scale materials. Background technique [0002] The uniaxial stress-strain curve is the most basic physical relationship of materials. It is the basic mechanical relationship required for mechanical performance testing (such as fatigue, fracture) and finite element analysis of materials and structures, and the optimization design and safety assessment of structural parts It is of great significance. The traditional test method is mainly to intercept standard uniaxial tensile specimens from raw materials or components, and the size of the specimens is of the decimeter and centimeter level. With the widespread application of miniaturization, lightweight components and expensive advanced materials and the development of minimally invasive sampling technology for service component...

AI Technical Summary

Problems solved by technology

With the widespread application of miniaturized, lightweight components and expensive advanced materials and the development of minimally invasive sampling technology for service components, material testing based on nano-specimen (millimeter, micron level) has begun to receive attention. In addition, in aerospace,

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