低碳Fe基Nb-Ti-V微合金化堆焊层的显微组织与性能

针对焊接快速成形耐磨功能零部件的需求,采用Nb-Ti-V微合金化的方法制备了一种低碳Fe基金属芯焊丝作为焊接成形材料,采用基于熔化极气体保护焊的焊接快速成形技术制备堆焊层试样,对其显微组织和性能进行了研究.显微组织分析表明:堆焊层金属无气孔和裂纹缺陷,主要组织是铁素体和板条马氏体,沿堆积高度方向上,马氏体的板条由粗大变为细小.堆焊层的硬度测试表明:显微硬度平均值为422.7 HV,具有一定的机加工性.干摩擦磨损试验表明:堆焊层的耐磨性是45钢的2.41倍.

Microstructure and properties of low carbon iron based Nb-Ti-V alloyed surfacing metal

In order to meet the demands for rapid forming functional parts with wear resistance,the low carbon Nb-Ti-V alloyed metal cored wires were developed to act as the forming materials.The surfacing metal samples were prepared by welding rapid forming technology based on gas metal arc welding.The microstructure and properties of the samples were studied.The results show that the surfacing metal is without pores and cracks,and the main microstructure is lath martensite and α ferrite,while the lathes change from coarse lathes to fine lathes along the deposition height direction.The average microhardness value is HV422.7,so the surfacing metal has acceptable working properties.The results of dry friction and wear test reveal that the wear resistance of surfacing metal is 2.41 times than that of 45 steel.