锁孔TIG焊接技术的研究进展

锁孔TIG焊接技术具有不开坡口、单面焊双面成形的特点,尤其适用于中厚板焊接。首先介绍了锁孔TIG焊的基本原理,然后分析了目前锁孔TIG焊接波形控制技术的研究现状,主要包括恒流锁孔TIG焊、单脉冲锁孔TIG焊和高低频双脉冲锁孔TIG焊。针对现有锁孔TIG焊接技术存在热输入量过大、接头组织晶粒粗大等缺点,重点介绍了一种新型的快频脉冲TIG焊接技术,它通过快频脉冲电流产生的电磁场对电弧进行压缩,控制焊接过程的热输入量,达到提高焊接质量的目的。与传统脉冲电弧相比,快频脉冲电弧的收缩效果更为明显,可细化焊接接头组织,将快频脉冲焊接技术应用于锁孔TIG焊是今后研究的热点和主要发展方向。

Research Progress of Keyhole TIG Welding Technology

The keyhole TIG welding has the feature of one-side welding with back formation and without groove. It is especially suitable for welding plates of moderate thickness. This paper first introduced the basic principle of keyhole TIG welding, and then analyzed the research status of the current general keyhole TIG welding waveform control technologies, including constant current keyhole TIG welding, single pulse keyhole TIG welding and high and low frequency double pulse keyhole TIG welding. In view of the shortcomings of keyhole TIG welding technology, such as too much heat input and coarse grain of joint structure, a new type of interpulse TIG welding technology was mainly introduced. It controlled the heat input in the welding process by compressing the arc with the electromagnetic field generated by the interpulse current, so as to improve the welding quality. Compared with the traditional pulse, the interpulse arc has obvious shrinkage effect which can refine the structure of welded joint. The application of interpulse welding waveform to keyhole TIG welding is the hot spot and main development direction in the future.