Strengthening Mechanisms for Ti-and Nb-Ti-micro-alloyed High-strength Steels  

作　　者：Chuan-feng MENG Yi-de WANG Ying-hui WEI Bin-qing SHI Tian-xie CUI Yu-tian WANG 

机构地区：[1]School of Materials Science and Engineering,Taiyuan University of Technology [2]Technology Center,Taiyuan Iron & Steel(Group)Co.,Ltd.

出　　处：《Journal of Iron and Steel Research International》2016年第4期350-356,共7页

基　　金：Item Sponsored by National Natural Science Foundation of China(51374151);Foundation for Key Program of Shanxi Province of China(20111101053);Foundation for Major Coal Base New Materials Program of Shanxi Province of China(MC2014-02)

摘　　要：The strengthening mechanisms of hot-rolled steels micro alloyed with Ti （ST-TQS00） and Nh Ti （NT TQ500） were investigated by examining the microstructures of steels using optical microscope （OM）, scanning elec tron microscope （SEM） and transmission electron microscope （TEM）. The results revealed ahnost no differences in the solute solution strengthening and fine grained strengthcning of the two steels, whereas the contributions of pre cipitation strengthening and dislocation strengthening were different for ST-TQ500 and NT-TQ500. The measured precipitation strengthening effect of ST-TQ500 was 88 MPa higher than that of NT-TQ500： this difference was pri marily attributed to the stronger precipitation effect of thc Ti-containing nanoscale particles. The dislocation strengthening effect of ST TQ500 was approximately 80 MPa lower than that of NT-TQ500. This is tbought to be related to differences in deformation behavior during the finishing rolling stage; the inhibition of dynamic recrystallization from Nb in NT-TQ500 （Nb-Ti） may lead to higher density of dislocations in the microstructure.The strengthening mechanisms of hot-rolled steels micro alloyed with Ti （ST-TQS00） and Nh Ti （NT TQ500） were investigated by examining the microstructures of steels using optical microscope （OM）, scanning elec tron microscope （SEM） and transmission electron microscope （TEM）. The results revealed ahnost no differences in the solute solution strengthening and fine grained strengthcning of the two steels, whereas the contributions of pre cipitation strengthening and dislocation strengthening were different for ST-TQ500 and NT-TQ500. The measured precipitation strengthening effect of ST-TQ500 was 88 MPa higher than that of NT-TQ500： this difference was pri marily attributed to the stronger precipitation effect of thc Ti-containing nanoscale particles. The dislocation strengthening effect of ST TQ500 was approximately 80 MPa lower than that of NT-TQ500. This is tbought to be related to differences in deformation behavior during the finishing rolling stage; the inhibition of dynamic recrystallization from Nb in NT-TQ500 （Nb-Ti） may lead to higher density of dislocations in the microstructure.

关 键 词：micro alloying TITANIUM NIOBIUM high-strength steel strengthening mechanism 

分 类 号：TG142.1[一般工业技术—材料科学与工程]