High Temperature Creep Rupture Characteristics of Ni-Based Alloy718 Jointed by Friction Welding |
Kwon Sang-Woo,Kong Yu-Sik,Kim Seon-Jin |
Department of Mechanical Design Engineering Pukyong National University,School of Mechanical Engineering Pukyong National University,School of Mechanical Engineering Pukyong National University |
마찰용접된 니켈기 초내열합금 Alloy718의 고온 크리프 파단 특성 |
권상우,공유식,김선진 |
부경대학교 기계설계공학과 대학원,부경대학교 기계공학부,부경대학교 기계공학부 |
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© 2008 The Korean Society of Ocean Engineers
Open access / Under a Creative Commons License
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Keywords:
Creep characteristics, Friction welding, Creep rupture time, Larson-Miller parameter LMP, Steady state creep rate(SSCR), Stress exponent |
핵심용어:
크리프 특성, 마찰용접, 크리프 파단시간, 정상상태 크리프 속도, 응력지수 |
Abstract |
The short-term high temperature creep rupture behavior of Ni-based Alloy718 steels jointed by friction welding wasinvestigated at the elevated temperatures of 550 to $700^{circ}C$ under constant stress conditions. The creep rupture characteristics such as creep stress, rupture time, steady state creep rate, and initial strain were evaluated. Creep stress has a quantitative correlation between creep rupture time and steady state creep rate. The stress exponents (n, m) of the experimental data at 550, 600, 650 and $700^{circ}C$ were derived as 26.1, -22.4, 22.5, -18.5, 17.4, -14.3 and 6.9, -8.1, respectively. The stress exponents decreased with increasing creep temperature. The creep life prediction was derived by the Larson-Miller parameter (LMP) method and the result equation obtained is as follows: T(logtr+20)=-0.00148${sigma}^2$-3.089${sigma}$+23232. Finally, the results were compared with those of the base metal for Alloy718. |
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