Weld Joint of Tantalum Sheet by Tungsten Inert Gas Welding

The 0.6 mm tantalum sheet was welded under argon atmosphere by Tungsten Inert Gas Welding (TIG) in order to obtain a welded joint with high-quality and high-reliability. Metalloscope, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were applied to analyze the joint. The results showed that the grain size of the base metal which affected by the welding heat remained the original size or enlarged slightly to 40-70 μm. What’s more, the weld zone was found to be composed of two components with different oxidation degree. And the distribution of these two components was related to the protection atmosphere of the location. The fusion line of the two tantalum sheets was clear which means high welding quality.