Classification of fatigue crack growth behavior

A self-consistent theory has been developed to account for the variation in fatigue crack growth rates with load ratio,R, without reference to crack closure concepts. The theory states that (a) for an unambiguous description of cyclic damage, two loading parameters are required; (b) consequently, there are two thresholds corresponding to each parameter that must be satisfied for a crack to grow; (c) these two thresholds are intrinsic and are independent of specimen geometry; (d) a fundamental threshold curve can be developed that is independent of test methods defining these two thresholds from the asymptotic values, and last; (e) the two thresholds vary with the degree of slip planarity, microstructure, and environment. Based on these new concepts, we have classified the entire fatigue crack growth behavior into five different classes using the experimental ΔKth-R data. The characteristic feature of each class is discussed, and the supporting examples of materials behavior are provided. This classification could provide a basis for understanding the synergistic effects of mechanical and chemical driving forces and microstructure contributing to fatigue crack growth.

[1]  B. R. Kirby,et al.  SLOW FATIGUE CRACK GROWTH AND THRESHOLD BEHAVIOUR IN AIR AND VACUUM OF COMMERCIAL ALUMINIUM ALLOYS , 1979 .

[2]  J. Petit,et al.  Environment and load ratio effects on fatigue crack propagation near threshold conditions , 1980 .

[3]  L. E. Culver,et al.  Fatigue Crack Propagation in Polymethylmethacrylate; the Effect of the Mean Value of Stress Intensity Factor , 1971 .

[4]  N. J. Mills,et al.  Craze growth and crack growth in poly(vinyl chloride) under monotonic and fatigue loading , 1976 .

[5]  Y. Mai,et al.  Temperature and enviromental effects on the fatigue fracture in polystyrene , 1979 .

[6]  A. Ueno,et al.  Crack propagation behavior of sintered silicon nitride under cyclic loads of high stress ratio and high frequency , 1991 .

[7]  P. C. Paris,et al.  Threshold for Fatigue Crack Propagation and the Effects of Load Ratio and Frequency , 1973 .

[8]  E. K. Priddle,et al.  System for Determining the Critical Range of Stress-Intensity Factor Necessary for Fatigue-Crack Propagation: , 1973 .

[9]  A. T. Stewart.  The influence of environment and stress ratio on fatigue crack growth at near threshold stress intensities in low-alloy steels , 1980 .

[10]  E. Priddle.  The influence of grain size on threshold stress intensity for fatigue crack growth in AISI 316 stainless steel , 1978 .

[11]  A. K. Vasudevan,et al.  Reconsideration of fatigue crack closure , 1992 .

[12]  S. Suresh,et al.  Oxide-Induced Crack Closure: An Explanation for Near-Threshold Corrosion Fatigue Crack Growth Behavior , 1981 .

[13]  A. K. Vasudevan,et al.  Two critical stress intensities for threshold fatigue crack propagation , 1993 .

[14]  S. Suresh.  Fatigue of materials , 1991 .

[15]  B. Weiss,et al.  An alternative presentation of the effects of the stress-ratio on the fatigue threshold , 1989 .

[16]  C. Gasc,et al.  THE INFLUENCE OF AGE‐HARDENING ON FATIGUE CRACK PROPAGATION BEHAVIOUR IN 7075 ALUMINIUM ALLOY IN VACUUM , 1983 .

[17]  H. Sumiyoshi,et al.  Variation of fractographic appearance for different microstructures in welded joints having the same fatigue crack propagation properties , 1987 .

[18]  R. J. Cooke,et al.  Slow fatigue crack propagation in pearlitic steels , 1974 .

[19]  R. J. Cooke,et al.  The slow fatigue crack growth and threshold behaviour of a medium carbon alloy steel in air and vacuum , 1975 .

[20]  K. Sadananda,et al.  Fatigue crack growth in metal matrix composites , 1993 .

[21]  S. Suresh,et al.  Mechanisms of Slow Fatigue Crack Growth in High Strength Aluminum Alloys: Role of Microstructure and Environment , 1984 .

[22]  K. Sadananda,et al.  A theoretical evaluation of crack closure , 1993, Metallurgical and Materials Transactions A.

[23]  K. Sadananda,et al.  A REVIEW OF CRACK CLOSURE, FATIGUE CRACK THRESHOLD AND RELATED PHENOMENA , 1994 .

[24]  Grzegorz Glinka,et al.  Rainflow counting algorithm for very long stress histories , 1987 .