Effect of Prestrain on Creep Behavior of Austenitic 25Cr-20Ni Stainless Steels

25Cr-20NirP 스테인리스강의 예변형에 의한 크리프 거동

  • Park, In-Duck (Division of Materials Science and Engineering, Pukyong National University) ;
  • Ahn, Seok-Hwan (Division of Materials Science and Engineering, Pukyong National University) ;
  • Nam, Ki-Woo (School of Mechanical Engineering, Pukyong National University)
  • 박인덕 (부경대학교 신소재공학부) ;
  • 안석환 (부경대학교 신소재공학부) ;
  • 남기우 (부경대학교 기계공학부)
  • Published : 2003.10.24

Abstract

25Cr-20Ni series strainless steel have an excellent high temperature strength, high oxidation and high corrosion resistance. However, further improvement can be creep strength by work hardening prior creep. In the present study, the effect of prestraining at room temperature on the creep behavior of a Class M(STS310S) and a Class A(STS310J1TB) alloy containing precipitates have been examined. Prestraining was carried out at room temperature and range of prestrain was $0.5{\sim}2.5$ % at STS310J1TB and $2.0{\sim}7.0$ % at STS310S. Creep behavior and creep rate of pre-strained specimens were compared with that of virgin specimens. Room temperature prestraining produced the creep life that is longer than that of a virgin specimen both for STS310J1TB and STS310S when creep test carried out at the temperature lower than recrystallization temperature. The reason for this improvement of creep life was ascribable to the interaction between dislocations and precipitates in addition to the dislocation-dislocation interaction in STS310J1TB and the dislocation-dislocation interaction in STS310S. The beneficial effect of prestraining in STS310J1TB was larger than that of STS310S.

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