Microscopic Response of TRIP Steels to Prestrain During Plastic Deformation  

作　　者：YU Hai-yan 

机构地区：[1]School of Automotive Engineering,Tongji University

出　　处：《Journal of Iron and Steel Research International》2013年第9期80-85,共6页

基　　金：Sponsored by National Natural Science Foundation of China(51175382);Fundamental Research Funds for Central Universities of China(2011)

摘　　要：In order to uncover the mechanism of elastic modulus degradation during plastic deformation, uniaxial ten- sile test of transformation-induced plasticity （TRIP） steels under different prestrain levels was carried out. The real elastic modulus unloaded at each prestrain was calculated by linearly fitting. The microstructure evolution with plas-tic strain and the fracture morphology were monitored by using a scanning electron microscope （SEM）. Dislocation density and its distribution were detected under a transmission electron microscope （TEM）. Microscopic mechanism of the elastic modulus degradation of TRIP steels was discussed in detail. Experimental results indicated that the in- vestigated TRIP600 steel was of severe elastic modulus degradation during plastic deformation. The new-born mar tensite distributed among the retained austenite, resulting in the combination of good ductility and high strength for TRIP steels. It was the change of dislocation movement that induced the variation of atomic binding force and finally led to the variation of elastic modulus.In order to uncover the mechanism of elastic modulus degradation during plastic deformation, uniaxial ten- sile test of transformation-induced plasticity （TRIP） steels under different prestrain levels was carried out. The real elastic modulus unloaded at each prestrain was calculated by linearly fitting. The microstructure evolution with plas-tic strain and the fracture morphology were monitored by using a scanning electron microscope （SEM）. Dislocation density and its distribution were detected under a transmission electron microscope （TEM）. Microscopic mechanism of the elastic modulus degradation of TRIP steels was discussed in detail. Experimental results indicated that the in- vestigated TRIP600 steel was of severe elastic modulus degradation during plastic deformation. The new-born mar tensite distributed among the retained austenite, resulting in the combination of good ductility and high strength for TRIP steels. It was the change of dislocation movement that induced the variation of atomic binding force and finally led to the variation of elastic modulus.

关 键 词：microstructural evolution TRIP steel plastic deformation elastic modulus PRESTRAIN 

分 类 号：TG142.15[一般工业技术—材料科学与工程]