固溶温度对17Cr-1Ni-3Mn-0.12N经济型不锈钢组织及力学性能影响  

Effect of solution temperature on microstructure and mechanical properties of 17Cr-1Ni-3Mn-0.12N lean stainless steel

作　　者：吕杰晟 宋志刚[1] 何建国 丰涵[1] 郑文杰[1] 朱玉亮[1] LÜJie-sheng;SONG Zhi-gang;HE Jian-guo;FENG Han;ZHENG Wen-jie;ZHU Yu-liang(Research Institute of Special Steels,Central Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]钢铁研究总院有限公司特殊钢研究院,北京100081

出　　处：《中国冶金》2023年第5期71-77,共7页China Metallurgy

摘　　要：针对一种新成分体系17Cr经济型不锈钢,通过室温拉伸试验、显微组织观察、X射线衍射等手段,研究了不同固溶温度对17Cr不锈钢显微组织和力学性能的影响,遴选出最佳的热处理温度区间,同时明确了固溶温度对该类型不锈钢奥氏体稳定性的影响。结果表明,17Cr不锈钢在900~1000℃固溶处理会发生上下屈服,1200℃固溶处理不发生相变诱导塑性(TRIP)效应,其最佳的固溶处理温度区间为1050~1150℃。不同固溶温度处理后试验钢均呈现铁素体、奥氏体和马氏体三相并存的组织;随着固溶温度升高,淬火马氏体相变发生率先降后增,奥氏体的热力学稳定性先升高后下降,同时TRIP效应减弱、抗拉强度降低、断后伸长率提高,奥氏体力学稳定性升高。分析拉伸试样断口可知,试样由马氏体处起裂呈解理断裂,而铁素体在断裂过程中阻碍了裂纹扩展。本研究为经济型双相不锈钢成分及显微组织设计提供了新的思路和理论基础。The effect of different solution temperatures on microstructure and mechanical properties of a new composition 17Cr lean stainless steel was studied by means of room temperature tensile tests,microstructure observation and X-ray diffraction,etc.The best heat treatment temperature was selected,and the effect of solution temperature on austenite stability of this type of stainless steel was also clarified.The results show that the 17Cr stainless steel will upper and lower yield at 900-1000℃,the TRIP effect will not occur at 1200℃,and the optimum solution treatment temperature range is 1050-1150℃.The specimens show three-phase structure of ferrite,austenite and martensite with different solution temperatures.With the increase of solution temperature,the thermomechanical stability of austenite first increases and then decreases,which shows the incidence rate of quenched martensite phase transformation first reduces and then grows.The mechanical stability of austenite increases with the increase of solution temperature,which shows that the TRIP effect slows down,the tensile strength decreases and the elongation increases.Analysis of the tensile specimen fracture shows that martensite is exhibiting deconvolution fracture,while ferrite hinders crack expansion through ductile fracture.This study provides new idea and theoretical basis for the composition and microstructure design of economical duplex stainless steel.

关 键 词：经济型双相不锈钢 淬火马氏体相变 形变诱导马氏体相变 TRIP效应 奥氏体稳定性 

分 类 号：TG142.71[一般工业技术—材料科学与工程] TG156.94[金属学及工艺—金属材料]