10CrNi3MoV钢MAG焊接头组织与力学性能研究

Microstructure and Mechanical Properties of MAG Welding Joint of 10CrNi3MoV Steel

采用MAG焊对8 mm厚的10Cr Ni3Mo V钢板进行焊接,借助光学显微镜、扫描电镜、HVS-10型硬度仪、WES600D液压万能试验机、JBN-300B冲击试验机等,对接头组织、硬度和力学性能等进行了研究。结果表明：焊缝组织为针状铁素体、少量的粒状贝氏体和沿柱状晶分布的先共析铁素体。粗晶热影响区晶粒较大,组织为粗大的马氏体。接头的硬度峰值在粗晶热影响区。接头拉伸性能优良,试样均断在母材。从焊缝到热影响区,冲击吸收功逐渐增加。

The welding of 10CrNi3MoV steel plate with thickness of 8 mm was carried out by using MAG welding, and the microstructure, microhardness and mechanical properties of the joint were analyzed by means of optical microscope,scanning electron microscope, HVS-10 hardness tester, WES600 D hydraulic universal testing machine and JBN-300 B impact testing machine. The results show that the weld microstructure consists of acicular ferrite, a small amount of granular bainite and proeutectoid ferrite distributed along the columnar crystal. The grain of coarse grain heat affected zone is large, and the microstructure is coarse martensite. The peak hardness of the joint is in the coarse grain heat affected zone. The tensile properties of the joint are excellent, and the samples are broken in the base material. From the weld to the heat affected zone,the impact absorbing energy gradually increases.