相变诱发塑性钢的应变硬化指数计算模型

Strain Hardening Exponent Calculating Model for Transformation Induced Plasticity Steels

摘要:

在连续介质力学和Eshelby夹杂理论的基础上,将相变诱发塑性(TRIP)钢中铁素体当作基体,其他相当作夹杂相,通过单向拉伸体单元模型,详细分析了各组成相及各夹杂相间的相互作用对材料整体硬化性能的贡献.并以各组成相体积比作为变量,建立了考虑相变诱发塑性效应的应变硬化指数计算模型.计算结果与实验结果及文献数据进行了比较,结果表明建立的应变硬化模型能正确地预测TRIP钢的应变硬化指数；TRIP钢应变硬化指数随应变呈抛物线变化,并非恒定不变.

Abstract:

Based on the continuum mechanical theory and Eshelby’s inclusion theory,a representative volume element model under uniaxial tension was built.The contribution of each constitute phases and their interaction to the overall strain hardenability of TRIP steels was analyzed in detail with the method of regarding ferrites the matrix and the other constitute phases the inclusions.With the volume fraction of retained austenites as a variable,a micromechanical model calculating strainhardening exponent considering transformation induced plasticity effect was proposed.Comparison between calculated strain hardening exponent with experimental result and published data shows the proposed model can predict the strainhardening exponent of transformation induced plasticity(TRIP)steels and strainhardening exponent can change with the plastic strain and fluctuates along a parabolic path instead of constant during the whole deformation.