考虑TRIP效应的QP980超高强度钢多相本构模型  

Multiphase constitutive model of ultra-high strength steel QP980 coupling with TRIP effect

作　　者：丁磊[1] 林建平[1] 庞政[1] 张铃[1] 

机构地区：[1]同济大学机械与能源工程学院,上海201804

出　　处：《塑性工程学报》2013年第4期23-26,共4页Journal of Plasticity Engineering

摘　　要：Q&P钢是一种高强度高塑性的第三代先进高强度钢种,合理的微观组织结构和塑性变形过程中引发的相变诱导塑性,是决定其力学性能的关键因素。通过SEM观察确定QP980的微观组织为板条马氏体、铁素体和残余奥氏体的混合组织。由XRD实验测量得到QP980钢板在单向拉伸状态下不同应变量对其残余奥氏体转化量的影响规律,发现QP980中残余奥氏体的体积分数随应变量的增加呈非线性下降的趋势。根据O-C马氏体相变动力学模型,得出QP980中残余奥氏体含量和等效应变的关系函数。根据等功原理和混合硬化准则,建立了考虑TRIP效应的QP980多相本构模型,并与QP980单向拉伸实验得到的应力应变曲线对比,验证了该模型的有效性。Q＆P steel is a 3rd generation advanced high strength steel with high strength level and excellent plasticity. Balanced mechanical properties attributes to the reasonable microstructure constitution and TRIP effect during deformation. First the mi- crostructure of QP980 was observed by scanned electron microscope, which is the combination of lath martensite, polygonal fer- rite and retained austenite. The variation of volume fraction of retained austenite with equivalent strain under uniaxial tensile state was obtained by X-ray diffraction measurement. It turns out the volume fraction of retained austenite decreased nonlinearly with the increasing of equivalent strain. The phase transformation kinetics equation of QP980 was deduced according to O-C theory. At last the muhiphase constitutive model of QP980 coupling with TRIP effect was established according to energy conservation and mixed hardening law. It is validated bv the comparison with strain stress curve by uniaxial tensile result.

关 键 词：Q&P钢 TRIP效应 O-C理论 多相本构模型 

分 类 号：TG142.7[一般工业技术—材料科学与工程]