工艺参数对堆焊熔敷成形极限倾角的影响规律

为了研究堆焊熔敷成形的极限倾角及送丝速度和堆焊速度对其的影响规律，采用MIG堆焊熔敷工艺进行单道多层成形试验，从焊缝形状变化及熔滴过渡方式的角度研究分析了成形极限倾角与工艺参数之间的关系.结果表明：极限倾角的大小主要由堆焊电流的大小决定并与成形焊缝形状有关，工艺参数对极限倾角的影响主要是通过改变堆焊电流、进而改变熔滴悬空部分所受力的平衡来实现的；在沿焊道方向上成形极限倾角为45°，且不受送丝速度和堆焊速度变化的影响.在垂直于焊道方向上，极限倾角随送丝速度的增大总体上呈减小趋势，随堆焊速度的增大呈先增大后减小趋势，当堆焊速度在18~21 mm/s时有最大值50°

Influence of technological parameters on limited lean in surfacing deposition forming process

In order to investigate the limited lean in surfacing deposition forming process as well as the influence of wire feeding speed and surfacing speed on the limited lean,a single bead and multi-layer forming test was carried out with MIG surfacing deposition technology.The relationship between the limited lean and technological parameters was analyzed on the basis of both weld shape change and droplet transition mode.The results show that the limited lean is mainly determined by surfacing current,and related to the weld shape.The effect of technological parameters on the limited lean is realized through changing the surfacing current and further varying the balance of force borne by the suspension section of droplet.The limited lean in the welding bead direction is 45°,and will not be affected by either wire feeding speed or surfacing speed.In the direction vertical to welding bead,the limited lean gradually decreases with increasing the wire feeding speed.With increasing the surfacing speed,the limited lean firstly increases,and then reduces gradually.The limited lean reaches the maximum value of 50° when the welding speed ranges from 18 mm/s to 21 mm/s.