铝合金熔丝增材制造表面平整度研究

Study on surface flatness of aluminum alloy by wire arc additive manufacturing(WAAM)

聚焦基于变极性冷金属过渡技术(CMT)的铝合金熔丝增材制造成形表面平整度,以一元化焊接送丝速度和横向相邻焊缝中心间距为变量,进行单层多道增材,通过结构光三维重构精确测量增材样品表面形状并使用平面拟合处理重构数据,定量计算增材表面高度方向上的极差和标准差。结果表明,在一定范围内增大送丝速度可以减少堆焊鱼鳞纹造成的偏差,但会引起焊道相对不稳定,致使增材样品表面总体平整度较差;而相邻焊缝中心间距与单道焊缝宽度的最佳比值与实际焊接工艺有关,仅靠曲线拟合单道焊缝形状和建立重叠模型不能计算预判所有焊接工艺条件下增材制造的成形质量。

The surface flatness of aluminum alloy component by wire arc additive manufacturing based on advanced cold metal transfer is studied The single-layer multi-pass deposit sample is carried out with various wire feed rates and horizontally adjacent weld center spacing.Structural-light three-dimensional reconstruction and plane fitting methods are used to accurately measure the component shape and quantitatively calculate the range and standard deviation of the deposited surface in the buildup direction.The results show that increasing the wire feed rate within a certain range can effectively reduce the deviation caused by surfacing fish scales,but the overall flatness is poor due to relative instability of bead.The optimum ratio of the adjacent weld center spacing to the single-pass weld width is related to the actual welding procedure,thus only by the curve fitting of the single-pass weld shape and establishing an overlapped model,it is impossible to calculate and predict the additive fabrication under all welding conditions.