基于焊道尺寸控制的电弧增材成形高氮奥氏体不锈钢与316L不锈钢交织结构

Mix structure of high nitrogen austenitic stainless steel and 316L stainless steel formed by wire and arc additive manufacturing based on size controlling of beads

采用高氮奥氏体钢与316L不锈钢丝材,对高氮奥氏体不锈钢熔覆焊道、单道多层、单层多道表面成形特性进行分析,筛选适宜的工艺参数。通过控制两种材料焊道尺寸,获得最适用于成形异材交织结构的工艺参数。利用不同道间距实验得到异材焊道的最佳道间距,并采用合理路径,制备电弧增材成形交织结构。结果表明:工艺参数的变化对高氮奥氏体不锈钢焊道表面成形特性影响极大,易出现气孔;提出异材焊道几何尺寸、截面面积匹配误差法,获得最佳工艺参数:其中高氮奥氏体钢丝材的送丝速率为5.7 m/min,316L不锈钢丝材的送丝速率为5.6 m/min,焊接速率均为0.6 m/min。通过降低起弧次数,采用闭合路径,提高了异材交织结构成形精度,减少了后处理加工。

Wires of high nitrogen austenitic stainless steel and 316L stainless steel were used,the surface forming characteristics of single bead,single-bead multi-layer and single-layer multi-bead were analyzed on high nitrogen austenitic stainless steel,better process parameters were screened.The most suitable process parameters of forming mix structure were obtained by size controlling of both beads.The optimum step-over distance of both beads was obtained by different step-over distance experiments,and mix structure was formed by wire and arc additive manufacturing with a reasonable path.The results show that the varies of process parameters have a great influence on surface forming characteristics of high nitrogen austenitic stainless steel beads,which pores emerge easily on the bead surface;the matching error method on geometry size and cross section area of both beads is proposed,by which optimum process parameters are obtained.The wire-feed rate of two wires are 5.7 m/min and 5.6 m/min,welding speed are both 0.6 m/min.Forming precision of mix structure is improved by reducing the number of arcing times and adopting a closed path,in addition,post processing decr-eases.