Improvement of Intergranular Corrosion Resistance of Type 316 Stainless Steel by Laser Surface Melting

Laser surface melting (LSM) on sensitised austenitic stainless steel with various degrees of cold work (5, 10, 15, 20, and 25%) was carried out by using a continuous wave CO₂ laser with a maximum power 450 W. The stainless steel was sensitised at 898 K for 10, 20, and 50 h durations. The ASTM A262 Practice A test was used to examine the microstructures of the specimens before and after LSM, while the single loop electrochemical potentiokinetic reactivation (SL-EPR) technique was used to quantify the degree of sensitisation (DOS). A trend is noted between the level of cold work in the stainless steel and the degree of desensitisation by LSM and it is inferred that laser surface melting can be effectively used as a method to improve the intergranular corrosion resistance of austenitic stainless steel.