Strengthening Mechanism of a New 700 MPa Hot Rolled High Strength Steel  

作　　者：YI Hai-long DU Lin-xiu WANG Guo-dong LIU Xiang-hua 

机构地区：[1]State Key Laboratory of Rolling Technology and Automation, Northeastern University, Shenyang 110004, Liaoning, China

出　　处：《Journal of Iron and Steel Research International》2008年第2期76-80,共5页

基　　金：Item Sponsored by High Technology Development Program of China(863)(2001AA332020);Project of National Natural Science Foundation of China(50271015)

摘　　要：The microstructural evolution in a 700 MPa hot rolled high strength steel was analyzed in terms of strengthening mechanisms.The results show that the hot rolled sheet steel has yield strength of 710 MPa with good elongation and toughness.The strength of the developed 700 MPa hot rolled high strength steel is derived from the cumulative contribution of fine grain size,dislocation hardening and precipitation hardening.The fine grain strengthening and precipitation hardening are the dominant factors responsible for such high strength,and the amount of precipitation hardening is two or four times higher than that of conventional microalloyed hot rolled sheet steels reported in the past.Good toughness is due to refinement of ferrite grain size.The microstructural evolution in a 700 MPa hot rolled high strength steel was analyzed in terms of strengthening mechanisms.The results show that the hot rolled sheet steel has yield strength of 710 MPa with good elongation and toughness.The strength of the developed 700 MPa hot rolled high strength steel is derived from the cumulative contribution of fine grain size,dislocation hardening and precipitation hardening.The fine grain strengthening and precipitation hardening are the dominant factors responsible for such high strength,and the amount of precipitation hardening is two or four times higher than that of conventional microalloyed hot rolled sheet steels reported in the past.Good toughness is due to refinement of ferrite grain size.

关 键 词：high strength steel strengthening mechanism dislocation hardening precipitation hardening 

分 类 号：TG11[金属学及工艺—物理冶金]