Effect of Solute Drag and Precipitate Pinning on Austenite Grain Growth in Ti-Nb Microalloyed Steels  

作　　者：FU Li-ming 1,WANG Huan-rong 2,WANG Wei 2,SHAN Ai-dang 1 (1.School of Materials Science and Engineering,Shanghai Jiaotong University,Shanghai 200240,China 2.Department of Structural Steels,Baosteel Research Institute,Shanghai 201900,China) 

出　　处：《Journal of Iron and Steel Research International》2011年第S1期383-387,共5页

摘　　要：A metallurgical model concerning the co-effect of the Nb solute drag and the complex carbonitride precipitates pinning is proposed to predict the recrystallization austenite grain growth of low carbon Nb-containing microalloyed steels.The analysis,both predicted and experimental,reveals the precipitate pinning plays a dominate role in suppressing the austenite grain growth with less Nb solute drag effect in high temperature region whereas the Nb solute drag predominates in relatively low temperature region.A factor p is suggested to assess the effectiveness of drag and pinning.The pinning and the drag are more effective in restraining grain growth as p】0 and p【0,respectively.A low carbon Nb microalloyed steel and a kind of Ti-modified low carbon Nb steel by Ti substituting for part of Nb are employed to validate the modeling results.The theoretical calculations show a good agreement with experimental results.A metallurgical model concerning the co-effect of the Nb solute drag and the complex carbonitride precipitates pinning is proposed to predict the recrystallization austenite grain growth of low carbon Nb-containing microalloyed steels.The analysis,both predicted and experimental,reveals the precipitate pinning plays a dominate role in suppressing the austenite grain growth with less Nb solute drag effect in high temperature region whereas the Nb solute drag predominates in relatively low temperature region.A factor p is suggested to assess the effectiveness of drag and pinning.The pinning and the drag are more effective in restraining grain growth as p>0 and p<0,respectively.A low carbon Nb microalloyed steel and a kind of Ti-modified low carbon Nb steel by Ti substituting for part of Nb are employed to validate the modeling results.The theoretical calculations show a good agreement with experimental results.

关 键 词：grain growth precipitates pinning solute drag Ti-Nb microalloyed steels 

分 类 号：TG142.33[一般工业技术—材料科学与工程]