Characteristic Evaluation according to Heat Treatment Conditions of Super Duplex Stainless Steel with Additive 0.2% N - Part 2: Fatigue Crack Propagation Behavior

J. Ocean Eng. Technol. 2009;23(5):79-84.

Ahn Seok-Hwan,Kang Heung-Joo,Seo Hyun-Soo,Nam Ki-Woo,Lee Kun-Chan

School of Mechanical Engineering Pukyong National University,Busan Maritime High School,Defence Agency for Technology and Quality,Division of Materials Science and Engineering Pukyong National University,Showa Denko K.K.

0.2% N을 첨가한 수퍼 2상 스테인리스강의 열처리 조건에 따른 특성 평가 - 제2보: 피로균열진전 거동

안석환,강흥주,서현수,남기우,이건찬

부경대학교 기계공학부,부산해사고등학교,국방기술품질원,부경대학교 신소재공학부,쇼와전공(주)

Keywords: Super duplex stainless steel, Fatigue crack propagation behavior, Heat treatment condition, Fatigue crack propagation rate, Stress intensity factor range

핵심용어: 수퍼 2상 스테인리스강, 피로균열진전거동, 열처리조건, 피로균열진전속도, 응력확대계수범위

Abstract

Super duplex stainless steel has long life in severe environments by showing the enough strength and corrosion resistance. Therefore, the fracture mechanics approach needs to support the structural strength integrity for the used material. In this study, fatigue crack propagation behavior was investigated to super duplex stainless steel with 0.2% nitrogen. The various volume fraction and distribution of austenite structure for applied specimen in test were obtained by changing the heat treatment temperature and cycle. From test results, fatigue crack propagation rate showed two kinds of tendency between da/dN and ${Delta}K$ according to distribution of austenite structure and structure anisotropy.