Keyhole gas tungsten arc welding of AISI 316L stainless steel

•10 mm-thick AISI 316L stainless steels can be welded by single-pass K-TIG process.•High-quality joints can be realized with high productivity and low cost.•The practical application of the K-TIG process in industry is well demonstrated.•An ideal process to weld mid-thickness 316L (thickness from 6–13 mm) is presented.

Keyhole gas tungsten arc welding (K-TIG) was used to weld AISI 316L stainless steel of mid-thickness (thickness ranging 6–13 mm). 316L plates of 10-mm thickness 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 welding with 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.

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