不同激光功率对Co基合金堆焊重熔层组织和性能的影响

Effect of different laser powers on structure and properties of Co-based alloy hardface remelted layer

研究了同一扫描速度(2mm/s)下,3种不同激光功率(1.5kW、2.0kW、2.5kW)对Co基合金堆焊层熔深、枝晶尺寸以及显微硬度和耐磨性的影响。试验结果表明,堆焊层经激光重熔后,组织较原始堆焊层明显细化,硬度明显提高。随着激光功率的加大,堆焊重熔层的熔深、枝晶尺寸均随之增大,表面硬度有所下降。但耐磨性并不随表面硬度下降而降低。硬度与耐磨性没有简单的对应关系。

The effect on the depth of remehed pool, the size of dendrites, the microhardness and wear-resistance of remehed layers have been studied with three kind of laser powers at the same scanning speed.The result showes that, the microstructure is finer than that of the original hardfaee layer after laser remelting. What＇s more, the micrphardness value is enhanced in evidence. As the depth of remehed pool and the size of dendrites are, increased, the surface hardness is dicreased with the laser powers enhanced. However, the wear rasistance doesn＇t decrease with the hardness decllning. The hardness has no simple corresponding relationship with the wear resistance.