The ductile-to-brittle transition behavior in ultra purified 17% Cr ferritic stainless steels
- 作者：GAO FeiLIU Zhenyu
- 会议时间：2013-06-01
- 关键词：ferritic stainless steel ; deformation twinning ; ductile-to-brittle transition
- 作者单位：The State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,Liaoning,China
- 母体文献：第五届宝钢学术年会论文集
- 会议名称：第五届宝钢学术年会
- 会议地点：上海
- 主办单位：中国金属学会
- 语种：chi
摘要
It is well known that ferritic stainless steels generally possess very low toughness,especially when their thickness is greater than 5mm.In order to work out the way for improving the toughness,in this work,the conventional and warm rolling processes have been carried out with an ultra purified ferritic stainless steel.After different rolling processes and subsequent recrystallization annealing,different recrystallized microstructural features had been obtained.The microstructure was investigated by using optical microscopy and electron backscattering diffraction ( EBSD) system.The fracture morphologies were observed by using a FE-SEM.It was observed that the warm rolling and subsequent recrystallization annealing could obviously refine the recrystallized microstructure of the hot band as compared to the conventional process.The ductile-to-brittle transition temperature ( DBTT) for the experimental steel was found to be closely related to the occurrence of deformation twinning,which could be suppressed by the refined microstructure by decreasing the critical temperature for the occurrence of twinning.Therefore,the DBTT was lowered to be below -40℃ and the toughness was significantly improved when the warm rolling process was applied,which has indicated the possibility for the replacement of thick gauge austenitic stainless steels such as AISI 304 by ferritic stainless steels in industrial applications.