화력 발전용 로터강의 초기 변형율이 CYCLIC 크리프 특성에 미치는 영향에 관한 연구

A Study on the Effect of Initial Strain on Cyclic Creep Properties of Steam Turbine Rotor Steel

  • 오세규 (부산수산대학교, 기계공학과) ;
  • 정순억 (부산수산대학교, 기계공학과) ;
  • 한상덕 (통영수산전문대학 기관학과)
  • 발행 : 1992.06.01

초록

The creep behaviors of 1%Cr-Mo-V and 12%Cr steam turbine rotor steels under static or cyclic load were examined at 600 and $700^{\circ}C$. The relationship between these two kinds of phenomena was studied and the experimental results were summarized as follows: 1) It is confirmed that the cyclic creep strain dependent on time is more available for creep, behavior analysis according to frequency change than that dependent on number of cycles, and the static creep, the special case of cyclic creep with stress ratio of 1 can be also more effectively analyzed by time-dependence. 2) The steady cyclic creep rate vs. the steady static creep rate, increases according to the increase of stress ratio, and this phenomena may occur on occasion of the decrease of the internal stress. 3) The initial strain affects on all the creep properties of the transient region, the steady state region and the rupture time in cyclic creep as well as static creep, and the quantitative relationships among them exist.

키워드

참고문헌

  1. Journal of Engineering Materials and Technology v.109 Relation Between Cyclic Creep and Pure Creep on Copper Ishikawa,H.
  2. 5th Int. Conf. on the Strength of Metal and Alloy v.1 Cyclic Creep Behavior and Internal Stress Meshii,M.;Ueki,M.;Chiou,H.D.
  3. The Fourteenth Japan Congress on Materials Research-Metallic Materials A Static-to-Dynamic Transition in Creep of Metallic Materials Under Cyclic Stress Conditions Ryoichi Koterazawa
  4. Materials Science and Engineering v.21 Cyclic Creep on Al-4.6%Mg at Moderate Temperatures Coutinho,C.B.;Matlock,D.K.;Bradley,W.L.
  5. 대한 기계학회 춘계학술대회 발표 논문집 화력 발전용 로터강의 초기 변형율법에 의한 장기 수명 및 강도 예측에 관한 연구 오세규;정순억
  6. 材料の 高溫强度論 平修二;大谷隆一
  7. Metallurgia v.76 no.455 The Effect of Stress Cycling on Creep and Fracture of Copper-7% Al Alloy Davies,P.W.;Wilshire,B.