The Effect of Welding Process on Mechanical Properties and Pitting Corrosion Resistance of Aisi 316l Austenitic Stainless Steel Welds

Abstract

The effect of welding process on mechanical properties and pitting corrosion resistance of AISI 316L austenitic stainless steel welds has been investigated using gas tungsten arc welding technique. The influence of the gas tungsten arc welding process on the toughness via the Charpy test, the hardness using Brinell hardness test, the tensile strength with the aid of a Universal tensile test machine and the pitting corrosion resistance by weight loss method were carried out on austenitic stainless steel 316L respectively. The welding process being a relatively high temperature process resulted in phase transformation in the weld and transition zone. Thereby culminating in observable differences in mechanical properties and pitting corrosion resistance between the parent material, transition zone and the weld. Higher concentration of austenite phase accounted for better mechanical properties in the transition zone and weldment. The weldment and HAZ being areas with lesser amount of Chromium and Molybdenum are the most probable for the initiation of corrosion pits and hence lesser pitting corrosion resistance compared to the parent material.