Enhancement of material properties of SS 316 L base metal by TIG cladding process

Abstract

The Tungsten Inert Gas (TIG) welding process was utilized to apply stainless steel (SS) 304 filler cladding onto the stainless steel (SS) 316 L base metal. This cladding resulted in an enhancement of the base metal's properties. An optical study and scanning electron microscope (SEM) analysis conducted to investigate the metallurgical properties revealed refined grain structures, indicating improved deposition of the SS 304 filler. The optical survey classified the different zones as base metal, weld metal, and transition line, with the transition line distinguishing the deposition of the filler metal through the cladding process. The refined grain structures, optimal process parameter selection (current, gas flow rate, and travel speed at a minimal level), and double-pass cladding have significantly influenced microhardness and tensile test values. The cladding of SS 304 fillers on SS 316 L alloys demonstrated improvement in the microhardness and tensile properties by 42.5 % and 13.2 %, respectively. Further investigation into the nozzle gun's heat input, current, and travel speed showed that maintaining a consistent travel speed with a steady heat source had a substantial impact on the material properties of the base metal.

Keywords

• Tungsten Inert Gas cladding
• Microstructure
• Microhardness
• And tensile properties