NbC增强Fe-Cr-C耐磨堆焊合金组织与磨粒磨损性能

以H08A为焊芯,在Fe-Cr-C耐磨合金焊条药皮中加入NbC,对堆焊层组织及NbC对堆焊层硬度和耐磨性的影响进行了研究.结果表明,NbC增强Fe-Cr-C耐磨合金的宏观硬度和耐磨性都高于Fe-Cr-C合金,宏观硬度达到61.6 HRC,比Fe-Cr-C耐磨合金提高9.6%;相对耐磨性提高60%.NbC增强Fe-Cr-C耐磨合金中NbC硬质相断面呈不规则形状,分布于M7C3之间,或镶嵌在M7C3中,以菱形或多边形居多,NbC分布不均匀,有局部聚集的区域.与Fe-Cr-C耐磨合金的共晶碳化物比较,Fe-Cr-C-NbC合金的共晶碳化物要粗大,共晶碳化物的间距也较大.

Microstructures and properties of Fe -Cr -C hardfacing alloy strengthened by NbC

NbC powder was added in coating of the Fe-Cr-C hardfacing electrodes.The effect of NbC on the microstructure and properties of deposited metal was studied.The results show that the NbC strengthened Fe-CrC hardfacing alloy has higher hardness and better abrasion wear-resisting property.The hardness of NbC strengthened Fe-Cr-C hardfacing alloy reach to 61.7 HRC,9.5% more than Fe-CrC hardfacing alloy.And the relative abrasion wear-resisting property of NbC strengthened Fe-Cr-C hardfacing alloy increased 60% comparing to the Fe-Cr-C hardfacing alloy.The cross shape of NbC hard phase in Fe-Cr-C-NbC alloy is erose,showing as rhombic or polygonal shape distributed between the M7C3 or embed in the M7C3.The distribution of NbC phase is not uniform,and it congregates in local regions.The eutectic carbides in the Fe-Cr-C-NbC alloy show coarse structure compared to the Fe-Cr-C hardfacing alloy,and the space betweer them is much great.