激光功率对激光熔化沉积CoCrNi中熵合金组织及性能的影响

Effect of laser power on microstructure and properties of entropy alloy in laser melting deposition of CoCrNi

采用激光熔化沉积工艺制备了CoCrNi中熵合金,研究了激光功率对组织及性能的影响。结果表明,当功率为800~1600 W时,沉积层与基体冶金结合良好,熔合线清晰可见。沿沉积层建筑方向组织依次为平面晶、柱状晶和等轴晶。随着功率升高,沉积层宽度增大,显微组织粗化,显微硬度逐渐降低。激光功率P=800 W时,性能最优,沉积层熔合区、中部和顶部的平均显微硬度分别为393、435和496 HV。

CoCrNi medium entropy alloy was produced by laser melting deposition process,and the influence of laser power on microstructure and properties was studied.The findings show that when the power is 800~1600 W,the metallurgical bonding between the deposition layer and the substrate is good,and the fusion line is clearly visible.The structure along the building direction of the deposition layer is planar crystal,columnar crystal and equiaxed crystal.With the increase of power,the breadth of the deposition layer increases,the microstructure coarsens,and the microhardness gradually decreases.The laser power is P=800 W,the performance is optimal,and the microhardness of the fusion zone,middle and top of the deposited layer is 393,435 and 496 HV.