Microstructures and mechanical properties of a martensitic steel welded with flux-cored wires  

作　　者：Weiqiang Zhang Zhimin Zhong Shaoguang Kang 

机构地区：[1]School of Environmental and Chemical Engineering,Shenyang Ligong University, Shenyang 110159, China [2]China Coal Zhangjiakou Coal Mining Machinery Co. Ltd.,Zhangjiakou 076250, China

出　　处：《International Journal of Coal Science & Technology》2015年第3期254-260,共7页国际煤炭科学技术学报（英文）

摘　　要：This study was focused on wear-resistant material prepared by CO2 GMAW method to basically determine the alloys and hardfacing technology which could be employed into mining equipment. Three flux-cored wires with different chemical compositions, marked by DM-I, DM-II and DM-III were used in welding a martensitic steel for the comparison of the microstructures and mechanical properties of the welding metals and HAZ. The results show that DM-I weld metal contains martensite plus other reinforced phases, while both DM-II and DM-III alloys lead to mainly martensitic microstructures with little precipitates. Among all of the tested materials the DM-I alloy has the highest hardness and wear resistance but the lowest impact toughness among the experimental weld metals. Meanwhile, the hardness, impact toughness and wear resistance of the DM-II and DM-III alloys are close to those of the base metal but the DM-III is not as strong as DM-II. Dimples can be found on the impact fracture of the weld metals, but the steel fracture consists of both cleavage and dimples. Thus HAZ has less risk for cracking than the welds, and the DM-II wire which produces the weld having identical mechanical properties to the base metal is suitable for further application.

关 键 词：HARDFACING MICROSTRUCTURE Mechanical property Flux-cored wire GMAW 

分 类 号：TG142.24[一般工业技术—材料科学与工程] TG146.21[金属学及工艺—金属材料]