Method for determining uniaxial stress-strain relationship of material based on high-temperature hydraulic bulging sample test

Abstract

The invention discloses a method for determining uniaxial stress-strain relationship of a material based on a high-temperature hydraulic bulging sample test, and the method comprises the following steps: preparing a test sample, carrying out a hydraulic bulging test on the test sample to obtain a pressure center deflection test curve of the test sample, and obtaining an external force work centerdeflection curve of the sample based on the pressure center deflection test curve, obtaining the yield strength and the strain hardening index of the material by utilizing the external force work center deflection curve, and further determining the uniaxial stress-strain relationship of the material. According to the method for determining the uniaxial stress-strain relationship of the material, the uniaxial stress-strain relationship of the material is obtained through a hydraulic bulging micro-sample test technology, and material parameters of the uniaxial stress-strain relationship curve ofthe material can be obtained only by simply analyzing and calculating a pressure center deflection test curve obtained through the test; the obtained result is high in precision, a large number of tests are not needed, the test method and the test principle are relatively simple, and engineering application is very convenient.

Description

technical field [0001] The invention belongs to the technical field of mechanical performance testing of ductile materials, especially the field of mechanical performance testing of rare, micro-scale materials and service component materials in high-temperature environments, and specifically relates to a material uniaxial stress- Strain relationship determination method. Background technique [0002] In the field of nuclear power, there are a large number of components that serve in complex environments such as high temperature and radiation. With the growth of time, the materials will inevitably undergo thermal aging, oxidation, corrosion and other phenomena, resulting in deterioration and damage of the materials. How to carry out the maintenance of the materials? Reliability and safety evaluation is of great significance. The traditional method is to conduct non-destructive testing or sampling tests on service components. Non-destructive testing can detect the uniformity ...

AI Technical Summary

Problems solved by technology

However, the current small punch test technology to obtain the yield strength and tensile strength of the material requires a large number of experiments in advance to establish the yield load, maximum load and yield strength obtained by the tensile test of large-scale specimens based on the small punch test. The corresponding relationship between strength and tensile strength, and finally obtain the empirical formula through the fitting of a large amount of data. The evaluation of conventional performance parameters such as tensile strength and fracture toughness is mostly empirical correlation, and the empirical correlation formulas obtained by different researchers are different; the test results are affected by the size of the steel ball, the rigidity of the steel ball, the degree of loading, and the friction coefficient between the steel ball and the sample. and other factors

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