Al和Mg元素对吉帕级熔敷金属组织和力学性能的影响  

Effect of Al and Mg elements on microstructure and mechanical properties of GPa-grade steel deposited metal

作　　者：栾宗锋 邸新杰[1] 利成宁 王佳美 LUAN Zongfeng;DI Xinjie;LI Chengning;WANG Jiamei(Tianjin University,TianJin,300350,China)

机构地区：[1]天津大学,天津300350

出　　处：《焊接学报》2022年第12期20-26,I0004,共8页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(52074191,51804217)。

摘　　要：针对吉帕级熔敷金属韧性不足的现状,设计了4组焊丝,研究了Al,Mg元素对金属粉芯焊丝熔敷金属组织和力学性能的影响.采用扫描电子显微镜对熔敷金属的显微组织进行了表征,通过力学性能测试表征了熔敷金属的力学性能.结果表明,熔敷金属主要由马氏体、贝氏体构成.随着熔敷金属中Al,Mg元素的添加量由0Al-0Mg增加至0.3Al-0.9Mg,其氧含量由0.030 8%降为0.014 3%,聚合贝氏体含量减少,板条马氏体含量增加.夹杂物由传统的以Fe,Al,Si,Mn等元素的氧化物转变为以Al,Mg氧化物为主的球形细小夹杂物(MgO·Al2O3).0.3Al-0.9Mg组与0Al-0Mg组相比较,夹杂物的平均尺寸降低了0.13μm,抗拉强度增加了152 MPa,冲击吸收能量增加了11 J (-20℃).In view of the insufficient toughness of the GPa-grade deposited metal, four groups of welding wires were designed to study the effects of Al and Mg elements on the microstructure and mechanical properties of metal cored welding wires. The microstructure of the deposited metal was characterized by scanning electron microscopy(SEM). The mechanical properties of the deposited metal were characterized by mechanical properties test. The results show that the deposited metal mainly consists of martensite and bainite. With the increase of Al and Mg contents from 0Al-0Mg to 0.3Al-0.9Mg,the content of O decreases from 0.030 8% to 0.014 3%, and the content of coalesced bainite decreases while that of lath martensite increases. and the inclusions were transformed from traditional oxides including Fe, Al, Si, Mn, etc. to spherical and fine particles mainly composed of Al and Mg oxides inclusions. Compared with 0Al-0Mg group, the average size of the inclusion in 0.3Al-0.9Mg group decreases by 0.13 μm, the tensile strength was increased by 152 MPa, and the impact absorption energy was increased by 11 J(-20 ℃).

关 键 词：吉帕级熔敷金属 Al和Mg联合脱氧 马氏体 氧化物夹杂 

分 类 号：TG422.3[金属学及工艺—焊接]