Developing novel arc plasma spot welding process

One of the key components in high-tech products, such as semiconductors, electronic connectors, and lithium batteries, is the lead frame, made from metals like copper and its alloys, as well as aluminum and its alloys, with thicknesses ranging from 0.02 mm to 0.8 mm. In manufacturing, butt-joint and overlap-joint welding are crucial for enhancing productivity and minimizing solid waste. However, existing welding technologies face challenges with these types of joints. To overcome this, a novel spot-welding process has been developed using an advanced welding torch with a dual-layer nozzle system, comprising an inner and outer nozzle. This design offers several advantages: it precisely positions the tungsten electrode, extends its lifespan, prevents molten metal from evaporating and re-entering the melt pool, and ensures arc plasma stability. Additionally, the outer nozzle plays a crucial role in controlling the shape of the arc plasma column, melt pool formation, and the size of the welded spot. By integrating both nozzles, this technology enables welding at an extremely short arc length and low current, ensuring minimal heat input while maintaining a high-stability arc plasma, making it ideal for welding ultra-thin metal sheets.