单道多层焊电弧增材制造成形研究

Research on single-pass and multilayer welding arc additive manufacturing

电弧增材制造的材料使用率高、成本低,但稳定性差、成形精度低,对增材制造件形貌进行分析,有利于提高其利用率。文章利用电弧增材制造方法,在Q235基板上进行单道多层焊实验,观察不同堆焊层数下的成形件情况,重点分析了焊接层数对成形件端部流淌的影响。结果表明:由于端部液态金属凝固过程中受多种力作用,随着焊接层数的增加,成形件两端出现流淌现象且逐渐加剧;成形件高度表现为中间高两端低,起弧端高于熄弧端;因下一层焊道对上一层焊道有重熔作用,随着焊接层数的增加,每一层焊道的高度也会增加,基板将会产生明显的焊接变形,当单道多层焊层数为20层时,其最大变形量可达3 mm。

The wire and arc additive manufacturing has the advantages of high material utilization and low cost.However,the process parameters have poor stability and low forming accuracy.The analysis of the structure of additive manufacturing is helpful to improve its utiliztion rate.This article uses the wire and arc additive manufacturing method to conduct a single-pass multi-layer welding process experiment on a Q235 substrate,observes the forming of the formed parts with different numbers of overlay layers,and focuses on the analysis of the effect of the number of welded layers on the flow problems at the ends of the formed parts.The results show that as the number of welded layers increases,the flow problem at both ends of the formed part gradually increases,and the reason for this is due to the comprehensive result of multiple forces acting during the solidification of the liquid metal at the end.The height of the formed part is high in the middle,the two ends are low,and the arc starting end is higher than the arc extinguishing end.Because the next layer of bead has a remelting effect on the previous layer,as the number of welding layers increases,the height of each layer of bead also increases;the substrate undergoes significant welding deformation.When the number is 20 layers,the maximum deformation is 3 mm.