The test results show that the CWW GMAW has 3 types of droplet transfer mode, namely rotation rejection transfer, globular transfer and projected transfer; and the CWW GMAW has 4 kinds of arc shape, which are scalene cylinder, circular truncated cone shape,

bell shaped and bunched shape。 During the process of CWW GMAW, the welding wire ends and the droplets were rotating constantly; the droplet fall into the molten pool with relative velocity, promoting the stirring effect of molten pool。 The anode region of CWW GMAW arc is coupled by multi-anode region。 When the current of CWW GMAW  was high, the electromagnetic force was large, and the arc was bundle shape, whose heat radiating area is small and the heat loss is relatively small。 The arc shape of  rotation transfer is scalene cylinder and circular truncated cone shape; the arc shape of globular transfer is bell shaped; the arc shape of projected transfer is  bunched  shape。 Welding current has the strongest effect on arc shape, and welding voltage is the next;  wire extension and welding speed have the weakest effect。 When the arc shape of CWW GMAW is scalene cylinder, the weld appearance is bad; weld surface has pores and dent defects and the welding splash is large; the weld depth is small and surplus height is big。 When the arc shape of CWW GMAW arc shape is bell shape, the weld appearance has significant improvement; the weld surface is smooth without obvious pore defects。 When the arc shape of CWW GMAW arc shape is bunched shape, the weld appearance is the best and the weld depth increase obviously。

Key words:   CWW GMAW；arc shape；weld appearance

目录

第一章 绪 论 1

1。1  课题背景 1

1。2  常见的高效焊接方法 1

1。2。1 高熔敷率焊接工艺 1

1。2。2 高速焊接工艺 2

1。2。3 其它高效焊接方法 2

1。3  缆式焊丝气保焊 3

1。3。1 缆式焊丝 3

1。3。2 缆式焊丝的特点 4

1。3。3 缆式焊丝气保焊的特点 4

1。4 缆式焊丝的研究现状 5

1。5  焊接电弧形态的研究现状 6

1。6 研究目的及内容 6

第二章 试验方法及材料 8

2。1  实验材料 8

2。1。1 药芯缆式焊丝 8

2。1。2 试用钢板 8

2。2  缆式焊丝气保焊试验系统 9

2。3  高速摄像及电信号采集系统 10

2。4  本章小结 10

第三章 缆式焊丝气保焊电弧形态分析 11

3。1  单丝气保焊电弧形态 11

3。2 缆式焊丝气保焊电弧形态分析 13

3。2。1 缆式焊丝气保焊电弧形态 13

3。2。2 缆式焊丝气保焊电弧形态分析 16

3。3  影响电弧形态的主要因素 17

3。3。1 焊接电流 17

3。3。2 电弧电压