304 스테인리스강의 열영향부에 미치는 탄소 함량과 용접 입열량의 영향

Abstract

As a result of welding 304 stainless steel which has a high carbon content containing 0.074wt.%C with an heat input of minimum 60kJ/in to investigate the effect of carbon content and welding heat input on the heat affected zone of austenitic stainless steels, a variety of tests to identify characteristics such as nondestructive properties, mechanical properties, chemical compositions, delta ferrire contents and structure observation satisfied all the requirements, but the intergranular corrosion by ASTM A262 test was observed at a specific location of the heat affected zone. The sensitization phenomena according to intergranular corrosion of the heat affected zone was confirmed by the temperature distribution analysis using SYSWELD 2014 program. However, as a result of welding 304 stainless steel which has a carbon content containing 0.064wt.%C with an heat input of minimum 60 kJ/in, the resistance to intergranular corrosion was confirmed in the heat affected zone. Therefore, it is deemed necessary to limit the maximum 0.65wt.%C of carbon content and maximum 60kJ/in of welding heat input to be applied to industrial field welding to ensure corrosion resistance of 304 series stainless steel in a corrosive environment.