Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403

공학

한국표면공학회지 (42권2호 79-85)

Development of a (16~19)Cr Ferritic Cast Stainless Steel for a Flange Material of Automotive Exhaust Parts

자동차 배기계 플랜지용 16~19 wt.% 페라이트 주조용 스테인리스강 개발

장희진;범원진;박찬진;
Jang, Hee-Jin;Beom, Won-Jin;Park, Chan-Jin;

조선대학교 금속재료공학과;전남대학교 신소재공학부;
Department of Metallurgical Engineering, Chosun University;Department of Materials Science and Engineering, Chonnam National University;

DOI : 10.5695/JKISE.2009.42.2.079

Abstract

We aimed to develop a Fe-($16{sim}19$)Cr-($0.1{sim}0.6$)Ti-($0.1{sim}0.6$)Nb stainless steel for automotive exhaust parts with high corrosion resistance. The alloys with high Cr content showed high resistance to general corrosion and also localized corrosion. The increase of Ti and Nb contents resulted in a linear increase in the general corrosion resistance, while the pitting potential was improved by addition of these elements up to about 0.4 wt.%. The low-carbon Fe-17Cr-0.4Ti-0.4Nb alloy annealed at $850^{circ}C$ and air-cooled was considered to be the optimum alloy for our purpose with the critical anodic current density of $247{mu}A/cm^2$ in 0.05 M $H_2SO_4$ solution and the pitting potential of 310 mVSCE in 0.2 M NaCl solution.

Keywords

Automotive exhaust parts;Ferritic stainless steels;Corrosion resistance;Response surface methodology;