等离子电弧增材成形件的表面平整度研究

Study on Surface Smoothness of Forming Parts by Plasma Arc Additive Manufacturing

一般等离子增材过程中,常选择余高较高的工艺参数进行增材,但所能达到的表面平整度有限。采用高氮钢焊丝进行等离子电弧增材,研究通过降低焊道余高提高成形体表面平整度。通过测厚仪结合设计公式表征表面平整度。研究了焊道搭接率、余高和路径规划方式对成形件表面平整度的影响规律。结果表明:余高较小的增材件平整度均优于余高较大的平整度,层层正交的成形件平整度优于层层堆焊的成形件平整度,并确定不同余高对应的合适搭接率范围。可见,降低焊道余高,选择合适的搭接率和路径规划方式可在一定程度上改善表面平整度。

In the general process of plasma additive manufacture process,the process parameters with higher residual height are often selected and the achieved surface smoothness is limited.The plasma arc additive manufacturing was carried out by using high-nitrogen steel welding wire.The improvement of surface smoothness of forming part was studied by reducing the reinforcement of the neld bead.The surface smoothness is characterized by thickness gauge combined with a design formula.The effect laws of overlap ratio,weld bead reinforcement and route planning mode on surface smoothness were investigated.The results show that the smoothness of the additive manufacturing parts with the smaller residual height is better than the smoothness of the additive manufacturing parts with the greater height.The smoothness of the layer-by-layer orthogonal forming parts is better than the smoothness of the layer-by-layer build-up welded parts,and the appropriate overlap ratio range corresponding to residual heights was determined.It can be seen that,the surface smoothness can be improved by reducing reinforcement and adopting appropriate overlap ratio and path planning method.