Application of Monkman-Grant Relationships to Type 316L(N) Stainless Steel

316L(N)스테인리스강의 Monkman-Grant 크리프 수명식의 적용성

Kim, U-Gon;Kim, Dae-Hwan;Ryu, U-Seok

  • Published : 2000.09.01


Creep tests for type 316L(N) stainless steel were carried out using constant-load creep machines at 55$0^{\circ}C$, 575$^{\circ}C$ and $600^{\circ}C$. Material constants necessary to predict creep rupture time were obtained from the experimental creep data. And the applicability of Monkman-Grant(M-G) and modified M-G relationships was discussed. The log-log plot of M-G relationship between the rupture time($t_r$,) and the minimum creep rate ($ $\varepsilon$ _m$) was dependent on test temperatures. The slope of m was 1,05 at 55$0^{\circ}C$ and m was 1.30 at $600^{\circ}C$. On the other hand, the log-log plot of modified M-G relationship between $t_r/$\varepsilon$_r$, and $ $\varepsilon$ _m$ was independent on stresses and temperatures. That is, the slope of m' was approximately 1.35 in all the data. Thus, modified M-G relationship for creep life prediction could be utilized more reasonably than that of M-G relationship for type 316L(N) stainless steel. It was analyzed that the constant slopes regardless of temperatures or applied stresses in the modified relationship were due to an intergranular fracture grown by wedge-type cavities.


Monkman-Grant Relationship;Modified Monkman -Grant Relationship;316L;Creep Curve;Creep Rupture;Minimum Creep Rate;Intergranular Fracture;Creep Cavity;N Stainless Steel


  1. Cadek, J., 1988, 'Creep in metallic materials, Elsevier, pp. 335-339
  2. Evans, R. W. and Wilshire, B., 1985, 'Creep of Metals and Alloys,' p. 10
  3. 김건영, 이강용, 1996, '금속조직 대비법에 의한 고온고압부 크리프손상의 수명평가,' 대한기계학회 96'재료 및 파괴부문 학술대회 논문집, KSME 96MF14, pp. 90-96
  4. Hosoi, Y. and Wade, N., 1984, 'Improvement of Creep Properties and Cavity Formation of Modified Type 316 Austenitic Stainless Steel by Microalloying with Phosphorus and Carbon,' Proc.2nd Int. Conf. on Creep and Fracture of Engineering Materials and Structures Part III, pp. 763-773
  5. Peny, R. K. and Marriott, D. L., 1995, 'Design for Creep,' Champan & Hall, p. 141
  6. Riedel, H., 1986, 'Fracture at High Temperature,' Spring-Verlag Berlin Heidelberg New York London Paris Torkyo, p.390
  7. Dobes, F. and Milicka, K., 1976, 'The Relation Between Minimum Creep Rate and Time to Fracture,' Metal Science, Vol. 10, pp. 382-384
  8. 김우곤, 김대환, 류우석, 국일현, 1998, 'AISI316L(N) 스테인리스강의 Creep 특성에 미치는 인(P)의 효과,' 한국원자력학회 추계학술대회, pp. 216-222
  9. ASTM, 1983, 'Standard Practice for Conducting Creep, Creep-Rupture, and Stress-Rupture Tests of Metallic Materials,' ASTM E139-83, pp. 305-315
  10. 김우곤, 김대환, 홍준화, 국일현, 류우석, 1999, 'Monkman-Grant 관계식에 의한 316L(N)강의 크리프 수명예측,' 대한기계학회'99 추계학술대회 논문집(A), pp. 175-180
  11. Nakazawa, T., 1988, 'Effects of Nitrogen and Carbon on Creep Properties of Type 316 Stainless Steels,' Proc. High Nitrogen Steels Conf. HNS 88, pp. 218-224
  12. 류우석 외, 1998, '액체금속로 구조재료 개요', KAERI/State-of-the Art Report(AR)-487/98
  13. Nabarro, F. R. N. and Villers, H. L., 1995, The Physics of Creep, Taylor & Francis Ltd., p. 22