Method for determining strain-induced martensite phase transformation kinetics curve

Abstract

The invention relates to a method for determining a strain-induced martensite phase transformation kinetics curve. The method comprises the following steps: S1, preparing a metal material containing ametastable austenite phase into a standard stretching test sample, and performing the stretching test to obtain a stress-strain curve; S2, preparing the metal material containing the metastable austenite phase into a stepped stretching test sample with N deformation sections, performing the stretching test under a same environment and strain rate with the step S1 until the test sample is broken;S3, determining a strain-induced martensite content fa' of N deformation section characteristic parts in the step S2; S4, obtaining N groups of strains sigma corresponding to a determination positionin step S3; and S5, obtaining a strain-induced martensite phase transformation kinetics curve containing a metastable austenite phase metal material. The method has the advantages that aiming at the metastable austenite phase metal material, while the metastable austenite phase metal material stress-strain curve data is measured, the strain-induced martensite transformation kinetics curve of the metalstable austenite phase metal material can also be measured, so that double benefits can be achieved.

Description

technical field [0001] The invention relates to the field of metal material analysis, in particular to a method for measuring strain-induced martensitic transformation kinetic curves. Background technique [0002] Improving the strength of metal materials without reducing their plastic deformation ability is an important direction in the research of metal structural materials. In the past experience, increasing the strength of metal materials often loses part of their plastic deformation ability. However, recent research results show that Designing the microstructure as a multiphase structure composed of a high-strength matrix phase and a hard second phase or metastable phase can simultaneously improve the strength and plasticity of metal materials, among which the high-strength matrix phase and metastable austenite phase The multiphase structure is widely used in the structure design of the third-generation advanced high-strength steel, and this structure design idea has be...

AI Technical Summary

Problems solved by technology

Obviously, the ex-situ method requires more experiments to obtain a credible strain-induced martensitic transformation kinetics curve, while the in-situ method has a small amount of experiments, but the resources of synchrotron radiation and neutron diffraction experimental devices are limited, so it is difficult Realized in common laboratory

Images