A Study on Material Degradation and Fretting Fatigue Behavior

재질 열화와 프레팅 피로거동 평가에 관한 연구

Gwon, Jae-Do;Seong, Sang-Seok;Choe, Seong-Jong

  • Published : 2001.08.01


Fretting is a potential degradation mechanism of structural components and equipments exposed to various environments and loading conditions. The fretting degradation, for example, for example, can be observed in equipments of nuclear, fossil as well as petroleum chemical plants exposed to special environments and loading conditions. It is well known that a cast stainless steel(CF8M) used in a primary reactor coolant(RCS) degrades seriously when that material is exposed to temperature range from 290$\^{C}$∼390$\^{C}$ for long period. This degradation can be resulted into a catastrophical failure of components. In the present paper, the characteristics of the fretting fatigue are investigated using the artificially aged CF8M specimen. The specimen of CF8M are prepared by an artificially accelerated aging technique holding 180hr at 430$\^{C}$ respectively. Through the investigations, the simple fatigue endurance limit of the virgin specimen is not altered from that obtained from the fatigue tests imposed the fretting fatigue. The similar tests are performed using the degraded specimen. The results are not changed from those of the virgin specimen. The significant effects of fretting fatigue imposed on both virgin and degraded specimen on the fatigue strength are not found.


Fretting fatigue;Degradation;Relative Slip;Friction Force;Non-Propagation Crack;Gross Slip;Partial Slip;Debris;Slip Band


  1. ASM Handbook, 1996, 'Fatigue and Fracture, edited by Steven R, Lampman, et al.,' Vol. 19, pp. 321-368
  2. ASTM, 'Conducting Constant Amplitude Axial Fatigue Tests of Metallic Materials,' ASTM E 46682, pp. 470-474
  3. Foury, S., Kapsa, P. and Vincent, L., 'Fretting-Wear and Fretting Fatigue: Relation Through a Mapping Concept,' Fretting Fatigue: Current Technology and Practices, ASTM STP 1367, pp. 49-64
  4. Jae-Do Kwon, Joong-Cheul Park, Yong-Son Lee, Woo-Ho Lee, Youn-Won Park, 2000, 'An Investigation of the Degradation Characteristics for Casting Stainless Steel, CF8M, Under High Temperatures,' Nuclear Engineering and Design 198, pp. 227-240
  5. 권재도, 박중철, 이용선, 이우호, 박윤원, 2000, '주조 스테인리스강 CF8M의 $430^{\circ}C$ 열화거동에 관한 연구(I)-열화기구.정적 및 피로강도평가,' 대한기계학회 논문집, 대한기계학회논문집A권, 제24권, 제8호, pp. 1910-1916
  6. Chopra, O. K. and Chung, H. M., 1989, 'Initial Assessment of the Process and Significance of Thermal Aging in Cast Stainless Steels,' NUREG/CP-097, Vol. 3, pp. 519-546
  7. Waterhouse, R. B., 1992, 'Standardization of Fretting Fatigue Test Method and Equipment,' ASTM STP 1159, pp. 60-66
  8. Chung, H. M. and Leax, T. R., 1989, 'Embrittlement of Laboratory and Reactor Aged CF-3, CF-8 Duplex Stainless Steel,' International Workshop on Intermediate-Temperature Embrittlement Processes in Duplex Stainless Steel, August 1-2, Oxford, England
  9. Solomon, H. D. and Levinson, Lionel M., 1978, 'Mossbauer Effect Study of 475$^{\circ}C$ Embrittlement of Duplex and ferritic Stainless Steels,' Acta Metallurgica, Vol. 26, pp. 429-442
  10. Waterhouse, R. B., 1972, Fretting Corrosion, Pergamon, Oxford
  11. Gillemot, F., 1995, Identification of NPP Key Components and Classification, Kins-IAEA Work on Technology for Life Management of NPPs