Probabilistic Mesomechanical Fatigue Crack Nucleation Model

A probabilistic mesomechanical crack nucleation model is proposed to link the microstructural material heterogeneities to the statistical scatter in the macrostructural response. The macrostructure is modeled as an ensemble of microelements. Cracks nucleate within the microelements and grow from the microelements to final fracture. Variations of the microelement properties are defined using statistical parameters. A micromechanical slip band decohesion model along with a Paris law crack growth model are used with first order reliability methods and Monte Carlo simulation to determine the distribution of fatigue life for the macrostructure. The modeled response is compared to trends in experimental observations from the literature.

[1]  Y. Ochi,et al.  Effects of Material Structures on Statistical Scatter in Initiation and Growth Lives of Surface Cracks and Failure Life in Fatigue , 1989 .

[2]  K. Chan,et al.  The crystallography of fatigue crack initiation in coarse grained astroloy at 20°C , 1989 .

[3]  Wilson H. Tang,et al.  Probability concepts in engineering planning and design , 1984 .

[4]  R. Miner,et al.  Fatigue crack initiation and propagation in several nickel-base superalloys at 650°C , 1983 .

[5]  T. Cruse,et al.  Advanced probabilistic structural analysis method for implicit performance functions , 1990 .

[6]  Fa Bastenaire,et al.  NEW METHOD FOR THE STATISTICAL EVALUATION OF CONSTANT STRESS AMPLITUDE FATIGUE-TEST RESULTS , 1971 .

[7]  Peter Joseph Edward Forsyth,et al.  The physical basis of metal fatigue , 1969 .

[8]  G. K. Haritos,et al.  Mesomechanics: The microstructure-mechanics connection , 1988 .

[9]  Toshio Mura,et al.  A Dislocation Model for Fatigue Crack Initiation , 1981 .

[10]  D. François.  The Influence of the Microstructure on Fatigue , 1989 .

[11]  J. Provan,et al.  Fatigue crack initiation and stage-I propagation in polycrystalline materials. I: Micromechanisms , 1991 .

[12]  Cyril Stanley Smith,et al.  A search for structure , 1981 .

[13]  Jaap Schijve,et al.  FATIGUE PREDICTIONS AND SCATTER , 1994 .

[14]  S. Kurtz,et al.  Microstructure and normal grain growth in metals and ceramics. Part I. Theory , 1980 .

[15]  M. A. Hicks,et al.  Effects of microstructure on long and short crack growth in nickel base superalloys , 1984 .

[16]  T. Ogawa,et al.  The effect of grain size on small fatigue crack growth in pure titanium , 1994 .

[17]  Ka Peters,et al.  Statistical Fatigue Failure Analysis , 1981 .

[18]  S. Shigemi,et al.  Some experimental studies of fatigue slip bands and persistent slip bands during fatigue process of low-carbon steel , 1979 .

[19]  Sankaran Mahadevan,et al.  Development of a reliability-based fatigue life model for gas turbine engine structures , 1996 .

[20]  W. Weibull.  CHAPTER II – FATIGUE TESTING METHODS , 1961 .

[21]  K. Tanaka,et al.  Grain Size Effect on Crack Nucleation and Growth in Long-Life Fatigue of Low-Carbon Steel , 1979 .