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 -Cr -C 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 -Cr -C 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 theM₇C₃ 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.