控冷冷速对Q390qE桥梁钢显微组织与力学性能的影响  

Effects of Controlled Cooling Rate on Microstructure and Mechanical Properties of Q390qE Bridge Steel

作　　者：刘宏伟[1] 臧振东 LIU Hongwei;ZANG Zhendong(School of Civil and Transportation Engineering,Qinghai Nationalities University,Xining 810000,China;Xining Special Steel Co.,Ltd.,Xining 810005,China)

机构地区：[1]青海民族大学土木与交通工程学院,青海西宁810000 [2]西宁特殊钢股份有限公司,青海西宁810005

出　　处：《热加工工艺》2024年第13期117-120,共4页Hot Working Technology

基　　金：青海省重大科技专项项目(2015-SF-A5)。

摘　　要：采用Gleeble-3500热模拟试验机模拟了Q390qE桥梁钢不同冷速的控冷工艺,并采用金相显微镜、透射电镜、万能试验机等研究了不同冷速对Q390qE钢微观组织与力学性能的影响。结果表明:冷却速度5~15℃/s的Q390qE试验钢,其组织主要为粒状贝氏体和少量针状铁素体。随着冷却速度的增加,Q390qE试验钢组织中贝氏体含量逐渐增加,试验钢的抗拉强度、屈服强度及屈强比不断提高。冷却速度5~10℃/s为Q390qE试验钢的理想控冷冷速,其屈服强度超过400 MPa,屈强比不超过0.83。Gleeble-3500 thermal simulation machine was used to simulate the cooling control process of Q390qE bridge steel with different cooling rates,and the effects of different cooling rates on the microstructure and mechanical properties of Q390qE steel were studied by metallographic microscope,transmission electron microscope and universal testing machine.The results show that Q390qE test steel with cooling rate of 5-15℃/s is mainly granular bainite and a small amount of needle ferrite.With the increase of cooling rate,the bainite content in Q390qE test steel microstructure increases gradually.The tensile strength,yield strength and yield strength ratio of the test steel are continuously improved.The cooling rate of 5-10℃/s is the ideal controlled cooling rate of Q390qE test steel,and its yield strength is more than 400 MPa,and the yield strength ratio is not more than 0.83.

关 键 词：Q390qE钢 冷却速度 显微组织 力学性能 

分 类 号：TG151.2[金属学及工艺—热处理]