具有TRIP效应高强韧钢的亚稳奥氏体演变规律、影响因素与增塑增韧机理

项目名称： 具有TRIP效应高强韧钢的亚稳奥氏体演变规律、影响因素与增塑增韧机理

项目编号： No.51474030

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 矿业工程

项目作者： 于浩

作者单位： 北京科技大学

项目金额： 80万元

中文摘要： 含亚稳奥氏体组织的钢具有高强塑性，此特点已广泛应用于量大面广且具有高技术含量的汽车用钢中，但目前对其形核长大的热动力学，稳定性与控制因素，基体组织类型、奥氏体状态与应变诱导产生的新相间的组织相容性与变形协调机理等方面尚不十分清楚。本项目将采用Thermo－Calc软件、原位扫描电子显微镜、透射电镜及背电子散射衍射技术等对TRIP钢、Q&P钢及TAM钢进行系统深入地研究，获得系统合金化原理，亚稳奥氏体、马氏体及界面之间的元素配分情况，建立组织转变热力学、动力学模型；获得亚稳奥氏体、基体与新生相间的晶体学位向关系、界面特征及精细结构，分析影响组织遗传、组织精细结构与其稳定性的因素，确定其主次关系并揭示其影响机理；阐明应变诱导产生的新相与基体间的变形协调机理及对裂纹扩展到影响。完善具有TRIP效应钢的合金化原理、相变及变形协调理论，为钢的组织性能综合控制与应用及新产品开发等提供理论和实验依据。

中文关键词： 亚稳奥氏体；元素配分；组织演变；界面；变形协调

英文摘要： The steel with metastable austenite microstructure has high strength-ductility property, and it has recently been widely applied to automobile steel with high technology. While the thermodynamics, stability and controlling factors of nucleation and growth, the matrix structure types, the austenite state, the histocompatibility and deformation compatibility mechanism among new phases produced by strain-induced are not revealed sufficiently, and systemtic researches are lacked. In this work, TRIP steel， Q&P steel and TAM steel with different metastable austenite formed processes were deeply studied by Thermo－Calc and softwares, in-situ scanning electronic microscope, transmission electron microscope, electron back scattered diffraction technology, etc. The systematic alloying fundamental and the element distribution situation among metastable austenites, martensites and interfaces are obtained, the simulation of thermodynamics and kinetics on microstructure transformation are builded; the crystal orientation relationship, interface characteristics and fine structures among metastable austenites, matrix and new phases are obtained, by studying the influence factors of structure inheritance, fine structures and its stability, the major and minor relationship is confirmed and the influence mechanism is revealed; the deformation compatibility mechanism among new phases produced by strain-induced and matrix and its influence on crack growth behavior are elucidated. According to above researches, the alloying principle, the theory of transformation and deformation compatibility, etc. of steel with TRIP effect are improved, providing theoretical and experimental basis for the comprehensive control of structure properties, application and new product development, etc.

英文关键词： metastable austenite;element partition;microstructure evolution;interface;deformation compatibility