Keyhole gas tungsten arc welding (K-TIG)was used to weld AISI 316L stainless steel of mid-thickness (thickness
ranging 6–13mm). 316L plates of 10-mmthickness were jointed using an I-groove in a single pass without filler
metal. The effects of welding parameters on the fusion zone profile were investigated. The weld properties,
including mechanical properties, microstructure, and corrosion resistance, were analyzed. The primary weld
microstructures were austenite and δ-ferrite. The tensile strength and impact property of the weld were almost
the same as those of the base metal, while the corrosion resistance of the weld was even better than that of the
base metal. High-quality 316L stainless steel joints can be realized through K-TIG weldingwith high productivity
and low processing cost. The practical application of K-TIG welding to join mid-thickness workpieces in industry
is well demonstrated and an ideal process for welding AISI 316L of mid-thickness with high efficiency and low
cost is presented.