Effect of Filler Metals on the Weldability and Mechanical Properties of Multi-pass PCGTA Weldments of AISI 316L

The influence of filler metals on the microstructure, mechanical properties, and corrosion behavior of AISI 316L welds was investigated. Pulsed current gas tungsten arc welding was employed to join the AISI 316L plates using two different fillers ER2553 and ERNiCr-3. Microstructures studies showed the presence of different forms of austenite on employing ER2553 filler and formation of migrated grain boundaries at the weld zone while using ERNiCr-3 filler. Tensile studies corroborated that the tensile strength was greater for the weldments employing ER2553 filler. Charpy V-notch studies ascertained that the impact toughness was greater for ER2553 weldments as compared to the parent metal. Potentiodynamic polarization curves clearly inferred that the weld zone of ER2553 exhibited better corrosion resistance among the various coupons tested. It was concluded from the study that ER2553 exhibited better mechanical and corrosion properties and could be adopted to achieve optimal properties compared to over-alloyed filler.