残留奥氏体转变行为对冷轧TRIP钢力学性能的影响  

Effect of transformation behavior of retained austenite on mechanical properties of cold-rolled TRIP steel

作　　者：付波 杨王玥[2] 李龙飞[3] 赵振业[1] 

机构地区：[1]北京航空材料研究院,北京100095 [2]北京科技大学材料科学与工程学院,北京100083 [3]北京科技大学新金属材料国家重点实验室,北京100083

出　　处：《材料热处理学报》2017年第12期63-69,共7页Transactions of Materials and Heat Treatment

基　　金：国家高技术研究发展计划项目(2007AA03Z501)

摘　　要：通过基于同步辐射技术的高能X射线衍射实验,对具有相同组织特征的低合金冷轧TRIP钢进行了室温和低温(-40℃)下的原位拉伸,观察拉伸变形过程中其残留奥氏体相的转变行为。结果表明:低温情况下TRIP钢组织中的残留奥氏体相稳定性降低,在弹性变形阶段以及塑性变形的前期便有大量残留奥氏体相发生马氏体转变,试样表现出较高的加工硬化能力。随着组织中残留奥氏体相的大量提前消耗,当变形进入高应变阶段时,TRIP钢组织因缺乏足够的马氏体转变,加工硬化能力快速下降,造成颈缩的提早出现,伸长率的降低。室温变形TRIP钢组织中残留奥氏体相的转变在整个变形过程中呈较平稳的趋势,TRIP效应能够持续发挥作用,特别是在变形的中后期仍能使组织保持较高的加工硬化能力,从而获得了较好的综合力学性能。Based on the in-situ high-energy X-ray diffraction technique,a low-alloyed C-Mn-Al-Si cold-rolled TRIP steel was tensile tested at room temperature and low temperature（-40 ℃）,and the transformation behavior of retained austenite in the steel was observed during tensile deformation. The results show that the stability of meta-stable retained austenite is reduced at low temperature,resulting in the transformation of retained austenite to martensite in the early stage of elastic deformation and plastic deformation,and the steel exhibits higher work hardening capabilities in the initial stage of deformation. With a large number of advance consumption of meta-stable retained austenite in the early stage,the martensitic transformation at middle and high strain deformation stage becomes insufficient,so the work hardening capabilities of the steel decreases rapidly,the necking is observed,and the elongation of the steel decreases. Compared to the low temperature deformation,the retained austenite in the TRIP steel deformed at room temperature transforms gradually into martensite during the whole deformation process,and the TRIP effect can continue to play a role,especially can still make the microstructure maintain higher work hardening capabilities at high strain deformation stage,so as to obtain a better combination performance of strength and ductility.

关 键 词：冷轧TRIP钢 残留奥氏体转变行为 高能X射线衍射 力学性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]