High frequency induction hot wire TIG welding of aluminum alloy

High frequency induction hot wire TIG (tungsten inert-gas) welding is a new technique with high efficiency and welding speed. Using the high frequency induction heating, the temperature and the heating length of the wire can be controlled. In addition, this technique can avoid magnetic blow aroused by loop current which is a main demerit of the ordinary hot wire TIG welding. Because this welding process heats the welding wire by high frequency induction, not the resistance, its can be applied to weld low resistance metal just like Al, Cu, etc. According to the principle of the inductance and working frequency, an induction coil and a sleeve adapted for φ1.6 mm Al wire were designed. Thermocouple was used to measure the temperature of the wire. The results show that when the wire feed rate is 6 m/min, the max temperature of the wire can achieve 450°C, and when the wire feed rate is as high as 10 m/min, the temperature of the wire can also approach 300°C, which meets the demand of the hot wire welding completely. Even the relative low wire feed rate of 6 m/min exceeds 3 times of routine TIG welding, which greatly improves the welding efficiency.