A7075-T6 알루미늄 합금의 프레팅 피로 손상 파라미터 비교 평가

국문 초록 (Abstract)

신뢰성이 가장 우수한 프레팅 피로손상 파라미터를 찾아내기 위해 알루미늄 합금 A7075-T6 을 대상으로 피로시험을 수행하였다. 시편 표면에 홈을 가공하여 패드 접촉압력에 따라 패드-시편 접촉면에서프레팅 피로균열이 발생하거나 또는 홈에서 일반 피로균열이 발생할 수 있게 하였다. 광학현미경을 이용하여 균열의 발생위치와 방향을 측정하고, 문헌에서 가장 많이 사용되는 프레팅 피로손상 파라미터들의 신뢰성을 평가하였다. 파라미터 값과 최대손상평면 방향을 산출하는데 필요한 응력과 변형률 자료는 유한요소해석으로 산출하였다. 전단모드 피로파손을 가정하는 Fatemi-Socie 파라 미터와 McDiarmid 파라미터가 가장 신뢰성이 높은 것으로 판명되었다.

다국어 초록 (Multilingual Abstract)

Fatigue tests were conducted on the aluminum alloy, A7075-T6 to determine the most reliable fretting fatigue damage parameter. Specimens with grooves were used, so that either fretting fatigue crack at the pad/specimen interface or plain fatigue crack at the groove could be nucleated, depending on the pad pressure. Both the crack nucleation location and initial crack orientation were examined using optical microscopy, and the results were used to assess the reliability of the various fretting fatigue damage parameters that have been most commonly used in the literature. Finite element analysis was employed to obtain the stress and strain data of the specimen, which were needed to estimate the parameter values and the orientation of the critical plane. It was revealed that both the Fatemi?ocie and McDiarmid parameters, which assume shear-mode fatigue cracking, are the most reliable.

목차 (Table of Contents)

• 초록
• Abstract
• 1. 서론
• 2. 피로 시험
• 3. 유한요소해석
• 4. 프레팅 피로 손상 파라미터
• 5. 피로 손상 파라미터 평가
• 6. 결론
• 후기
• 참고문헌

참고문헌 (Reference)

1 Hattori, T, "Torsional Fatigue Strength of a Shrink-Fitted Shaft" 24 (24): 1893-, 1981

2 Gassner, E, "The Value of Surface-Protective Media Against Fretting Corrosion on the Basis of Fatigue Strength Tests" Laboratorium fur Betriebsfestigkeit 1967

3 Wharton, M. H, "The Effect of Different Contact Materials on the Fretting Fatigue Strength of an Aluminum Alloy" 26 : 253-, 1973

4 Hattori, T., "Slipping Behavior and Fretting Fatigue in the Disk/Blade Dovetail Region" 945-, 1984

5 Navarro, C, "On the Use of Multiaxial Fatigue Criteria for Fretting Fatigue Life Assessment" 30 : 32-44, 2008

6 Szolwinski, M. P, "Mechanics of Fretting Crack Formation" 198 : 93-107, 1996

7 Swalla, D. R, "Influence of Coefficient of Friction on Fretting Fatigue Crack Nucleation Prediction" 34 : 493-503, 2001

8 Milestone, W. D, "Friction Between Steel Surfaces During Fretting" 18 : 29-40, 1971

9 King, R. N, "Fretting Fatigue in a 3.5 Ni–Cr–Mo–V Rotor Steel" 631-, 1980

10 Hattori, T, "Fretting Fatigue Analysis by Using Fracture Mechanics" ASME 1984

11 Tsai, C.T, "Elasto-Plastic Finite Element Analysis of Fretting Stresses in Prestressed Strip in Contact with Cylindrical Pad" 36 : 171-187, 2000

12 Crossland, B, "Effect of Large Hydrostatic Pressures on the Torsional Fatigue Strength of an Alloy Steel" 138-149, 1956

13 Dominguez J, "Cyclic Variation in Friction Forces and Contact Stresses During Fretting Fatigue" 218 : 43-53, 1998

14 Lykins, C. D., "An Evaluation of Parameters for Predicting Fretting Fatigue Crack Initiation" 22 : 703-716, 2000

15 Smith, K. N, "A Stress–Strain Function for Fatigue of Metals" 5 (5): 767-778, 1970

16 McDiarmid, D. L, "A Shear Stress Based Critical-Plane Criterion of Multiaxial Fatigue Failure for Design and Life Prediction" 17 : 1475-1484, 1994

17 Fatemi, A, "A Critical Plane Approach to Multiaxial Fatigue Damage Including Out-of-Phase Loading" 11 : 145-165, 1988