摘要
对含碳量0.35wt%的无碳化物高强贝氏体钢进行等温贝氏体相变试验,并通过膨胀法、显微组织观察、XRD和拉伸试验等方法研究奥氏体化温度(860~1260℃)对该贝氏体钢相变和组织性能的影响。结果表明,860℃奥氏体化时,贝氏体转变量略高于其它温度,残余奥氏体含量较高,继续升高奥氏体化温度,贝氏体转变量和残奥含量变化不大。此外,随着奥氏体化温度的升高,贝氏体相变动力学加快,这是原始奥氏体晶粒尺寸增加,贝氏体生长空间增大引起的。当奥氏体化温度较低时,虽然贝氏体相变速率较慢,但由于原始奥氏体晶粒细化,残奥含量较多等原因,钢的抗拉强度和伸长率均较高。因此,从提高钢性能角度出发,应降低无碳化物高强贝氏体钢热处理时的奥氏体化温度。
The isothermal bainitic transformation test of carbide-free high strength bainitic steel with carbon content of0.35 wt%was carried out.The effects of austenitizing temperature(860-1260℃)on the transformation,microstructure and properties of the bainitic steel were studied by expansion method,microstructure observation,XRD and tensile test.The results show that,the bainite transformation content at 860℃is slightly higher than that at other temperatures,and the retained austenite content is higher.With the increase of the austenitizing temperature,the bainite transformation and the residual content of the austenite changes litte.In addition,with the increase of austenitizing temperature,the transformation kinetics of bainite is accelerated.This is caused by the increase of the original austenite grain size and the increase of the bainitic growth space.When the austenite temperature is low,although the bainitic transformation rate is slow,the tensile strength and elongation of the steel are higher due to the refinement of the fine original austenite grain and the high residual austenite content.Therefore,from the point of improving the properties of steel,the austenitizing temperature of the carbide-free high strength bainitic steel during heat treatment should be reduced.
作者
周明星
周世明
张万顺
刘蒙恩
雷震霆
ZHOU Mingxing;ZHOU Shiming;ZHANG Wanshun;LIU Meng'en;LEI Zhenting(School of High Temperature Materials and Magnesite Resources Engineering,University of Science and Technology LiaoNing,Anshan 114051,China;School of Mechanical&Automotive Engineering,Nanyang Institute of Technology,Nanyang 473004,China)
出处
《热加工工艺》
北大核心
2020年第4期122-125,128,共5页
Hot Working Technology
基金
河南省高等学校重点科研计划项目(20A430020)
南阳理工学院博士科研启动项目(182102210463).
关键词
无碳化物贝氏体钢
奥氏体化温度
贝氏体相变
显微组织
力学性能
carbide-free bainite steel
austenitization temperature
bainite transformation
microstructure
mechanical properties
作者简介
周明星(1991-),男,河南南阳人,讲师,博士,主要研究方向:金属材料加工与组织性能控制,电话:16638761265,E-mail:kdmingxing@163.com通讯作者:张万顺(1989-),男,河南焦作人,助教,硕士,主要研究方向:金属材料加工工艺优化,电话:15242208693,E-mail:aswanshun@163.com
