Solution and Precipitation Behavior of Nb and Its Role in Medium Carbon Long Product Steels  

作　　者：Zhang Yongqing Wang Maoqiu Yong Qilong Jose MRodriguez-Ibabe Leonardo Silvestre 

机构地区：[1]China Iron&Steel Research Institute Group,No.76 Xueyuan Nanlu,Haidian,Beijing 100081,China [2]CITIC Metal Co.,Ltd.,Room 1901 Capital Mansion,Beijing 100004,China [3]Ceit Research Institute,P.M.Lardizabal 15,Donostia San Sebastian 20018,Spain [4]CBMM,Av.Brg.Faria Lima,4285,São Paulo-SP 04538-133,Brazil

出　　处：《Journal of Mechanics Engineering and Automation》2022年第1期1-14,共14页机械工程与自动化（英文版）

摘　　要：Controlling of the solution and precipitation for microalloying additions of Nb,V,Ti and their combination is the basic building block of microalloyed steels.Among three microalloying elements,Nb has been regarded the most effective microalloying ingredient used for low carbon flat products due to marked strengthening effect of grain refinement and relatively weak precipitation strengthening effect by matching proper thermomechanical processing(TMP).However,Nb was not viewed as attractive as V for medium carbon long products in the past because of limited solubility during reheating process.What is more,hot working is usually carried out at high temperatures in the recrystallization regime,so it is difficult to exert conventional controlled rolling to obtain pancaked austenite,which has further affected the research and application of Nb in medium carbon long products.Because of these factors,studies of Nb in medium carbon long products were incomplete,and even some recognitions and conclusions are subjected to debate.In order to clarify the strengthening effects of Nb in medium carbon long products,the reinforcing bars have been chosen as experimental steels to clarify the role of Nb on microstructural changes along the whole hot working,cooling processes.In addition,qualitative and quantitative analyses of Nb’s state and distribution in reheating,rolling and cooling had been carried out to illustrate some singularities.

关 键 词：Nb microalloying solution and precipitation transformation strengthening HARDENABILITY 

分 类 号：TG1[金属学及工艺—金属学]