Microstructure and mechanical properties of AISI 347 stainless steel/A335 low alloy steel dissimilar joint produced by gas tungsten arc welding

• There is carbon migration from HAZ to the melt zone in the interface between A335 low alloy steel and 309L filler metal.
• The maximum fracture energy was related to the ERNiCr-3 weld metal specimen.
• In the tensile test, all specimens were broken in the HAZ of A335 low alloy base metal.
• The ERNiCr-3 filler metal is the best choice for the joint between 347 austenitic stainless steel and A335 low alloy steel.

In the present study, microstructure and mechanical properties of AISI 347 austenitic stainless steel/ASTM A335 low alloy steel dissimilar joint were investigated. For this purpose, two filler metals including ER309L and ERNiCr-3 were selected to be used during the gas tungsten arc welding process. In tension tests, all weldments failed in the HAZ of A335. The impact test results indicated that all specimens exhibited ductile fracture. The maximum fracture energy was related to the ERNiCr-3 weld metal specimen. The maximum and minimum hardness corresponded to the ERNICr-3 and ER309L. Finally, it was concluded that ERNiCr-3 filler metal was the best choice for the joint between 347 austenitic stainless steel and A335 low alloy steel.