回火对低碳贝氏体钢组织和性能的影响  

Influence of Tempering on Microstructure and Properties of Low Carbon Bainite Steel

作　　者：黄少文[1] 

机构地区：[1]莱芜钢铁集团有限公司宽厚板事业部,山东莱芜271100

出　　处：《山东冶金》2015年第5期45-48,共4页Shandong Metallurgy

摘　　要：研究了（250-500）℃×30 min回火热处理对低碳贝氏体钢组织和性能的影响。结果表明,TMCP状态试验钢的组织为粒状贝氏体、板条贝氏体和针状铁素体。回火温度升高,粒状贝氏体增加,板条贝氏体和针状铁素体减少,组织逐渐粗化。350℃回火时,试验钢的屈服强度（Rt0.5）为735-765 MPa,抗拉强度（Rm）为845-865 MPa,屈强比为0.87-0.88,-20℃冲击功为218-257 J,强韧性匹配最佳。300-400℃回火时,裂纹形成能（E1）、韧性裂纹扩展能（E2）及脆性裂纹扩展能（E3）＋脆性裂纹扩展止裂能（E4）最大,止裂性能最佳。The effects of tempering process kept from 250 ℃ to 500 ℃×30 min on microstructure and properties of low carbon bainite steel were investigated. The test results show that microstructure of TMCP test steel consists of lath bainite（LB）, granular baintie（GB）,acicular ferrite（AF）. With increasing of the temper temperature, volume fraction of GB increased, LB and AF decreased. After tempered at 350 ℃, the test steel＇s Rt0.5is 735-765 MPa, Rmis 845-865 MPa, Rt0.5/Rmis 0.87-0.88, impact energy-20 ℃ is 218-257 J, the strength and toughness are improved. When the tempering temperature is between 250-400 ℃, the crack formation energy（E1）, ductility fracture propagating energy（E2） and brittle crack propagation energy（E3） ＋ brittle crack arrest energy（E4） are better, that presents a good anti-crack ability.

关 键 词：低碳贝氏体钢 回火 显微组织 强韧性 

分 类 号：TG142.1[一般工业技术—材料科学与工程] TG156.5[金属学及工艺—金属材料]