摘要
工程机械用高强钢Q960E的焊接热影响区存在脆化和软化等焊接性问题。为解决该问题,采用焊接热模拟技术,设置不同的预热温度与线能量参数,获得焊接热影响区并通过显微组织分析和力学性能测试,探究预热温度以及线能量对焊接热影响区组织和力学性能的影响。结果表明,Q960E钢的焊接热影响区组织以低碳马氏体和贝氏体组织为主。随预热温度的升高,贝氏体含量增加,并开始出现粒状贝氏体脆性组织。焊接热影响区的抗拉强度随预热温度的升高略有降低。预热温度对焊接热影响区的显微硬度的影响不大。低温冲击韧性随预热温度的升高先增加后减小。在试验条件下,焊接线能量为1.5 kJ mm和预热温度为150℃时,获得的焊接热影响区组织综合力学性能最好。
The welding heat-affected zone of high-strength steel Q960E used in engineering machinery has welding problems such as embrittlement and softening.To solve this problem,the welding thermal simulation technology was adopted,different preheating temperatures and heat inputs were set,the welding heat-affected zone was obtained,and the effects of preheating temperature and heat inputs on the microstructure and mechanical properties of the welding heat-affected zone were explored through microstructure analysis and mechanical property testing.The results indicate that the microstructure of the welding heat-affected zone of Q960E steel is mainly composed of low-carbon martensite and bainite.As the preheating temperature increases,the content of bainite increases and granular bainite brittle structure begins to appear.The tensile strength of the welding heat-affected zone slightly decreases with the increase of preheating temperature.The preheating temperature has little effect on the microhardness of the welding heat-affected zone.The low-temperature impact toughness first increases and then decreases with the increase of preheating temperature.Under experimental conditions,the best comprehensive mechanical properties of the welding heat affected zone microstructure were obtained when the welding line energy was 1.5 kJ mm and the preheating temperature was 150℃.
作者
王越洋
李硕妍
王鑫
杨永强
郑春雷
WANG Yueyang;LI Shuoyan;WANG Xin;YANG Yongqiang;ZHENG Chunlei
出处
《大型铸锻件》
2024年第6期108-112,共5页
Heavy Casting and Forging
关键词
Q960E钢
焊接热影响区
预热温度
显微组织
力学性能
Q960E steel
welding heat-affected zone
preheating temperature
microscopic structure
mechanical properties
