文献类型：期刊文献

中文题名：单轴拉伸过程中双相不锈钢局部微观变形行为的细观力学有限元分析

英文题名：Micromechanics Finite Element Analysis of Local Micro-Deformation Behaviour of Duplex Stainless Steel under Uniaxial Tension

作者：史艳茹[1];苑光健[1];郭素娟[1]

机构：[1]华东理工大学机械与动力工程学院动力工程及工程热物理系(承压系统与安全教育部重点实验室),上海200237

年份：2020

卷号：41

期号：1

起止页码：29

中文期刊名：力学季刊

外文期刊名：Chinese Quarterly of Mechanics

收录：CSTPCD;;北大核心:【北大核心2017】；CSCD:【CSCD_E2019_2020】；

基金：国家自然科学基金(11872181,11302079);上海市自然基金(18ZR1408900)。

语种：中文

中文关键词：双相不锈钢;纳米压痕;Voronoi;Tessellation法;有限元分析;局部应力应变分布

外文关键词：duplex stainless steel;nano-indentation;Voronoi Tessellation method;finite element analysis;local stress-strain distribution

摘要：针对双相不锈钢中奥氏体相和铁素体相分别展开了纳米压痕实验,并通过有限元反演得到两相各自的拉伸应力-应变关系,利用Voronoi Tessellation法生成代表性的微结构体积单元,对双相不锈钢的单轴拉伸行为进行了有限元仿真和模拟,研究了双相不锈钢在拉伸过程中的局部应力、应变分布和演化规律.结果表明,利用Voronoi Tessellation法建立单元模型,结合本文通过纳米压痕实验获取的两相力学性能参数,可以很好地模拟双相不锈钢的整体单拉行为,奥氏体比铁素体软,拉伸载荷下双相不锈钢的应变集中在奥氏体中,应力集中在铁素体中;局部应力应变的分布特征与两相分布特征和晶粒形状有关,最大应变值主要集中在奥氏体晶粒狭长且尖锐的区域,而最大应力则主要发生在铁素体晶粒狭长和尖锐的区域;对于奥氏体和铁素体晶粒占比相当的双相不锈钢,其虽然可以具有较为综合的宏观力学性能,但是其微观应力集中的区域和应力最大值相对较大.研究成果为进一步揭示双相不锈钢局部失效机理奠定了基础.
The nanoindentation experiment was carried out on the austenite phase and the ferrite phase in the duplex stainless steel, and the uniaxial tensile curves of the two phases were obtained by the finite element inversion analysis method. The local stress, strain distribution and the evolution law of duplex stainless steel during the tensile loading condition were studied by using the Voronoi Tessellation method to generate representative microstructure volume units and simulating the uniaxial tensile behavior of duplex stainless steel with finite element method. The results show that the proposed approach in this paper can well simulate the overall uniaxial behavior of duplex stainless steel. Generally, austenite phase behaves softer than ferrite phase. The strain of duplex stainless steel under tensile load is concentrated in austenite phase, while the stress is concentrated in ferrite phase. The distribution characteristics of local stress and strain are related to the two-phase distribution characteristics and the grain shape, with the maximum strain occurring mainly in the narrow and sharp austenite areas and the maximum stress in the narrow and sharp ferrite areas. For duplex stainless steels with comparable austenite and ferrite proportions, a more balanced macro mechanical property has been observed. However, the area of microscopic stress concentration and the maximum stress are relatively large. This research lays the foundation for further revealing the local failure mechanism of duplex stainless steel.