Accession Number : AD0763776

Title :   On the Influence of the R-Ratio on Fatigue Crack Propagation,

Corporate Author : CONNECTICUT UNIV STORRS DEPT OF METALLURGY

Personal Author(s) : McEvily,A. J. ; Kumble,R. ; Donahue,R. J.

Report Date : FEB 1973

Pagination or Media Count : 10

Abstract : A model of the fatigue crack growth process based on crack opening displacement considerations has been previously applied successfully to crack growth under R=O type loading. (R is the ratio of the minimum to the maximum stress of a loading cycle). The present work extends the approach to include other R ratios. A comparison of experimental results indicates crack closure effects influence the crack growth behavior. A modification of the expression for crack growth to reflect crack closure is proposed. This expression is in better agreement with experiment. (Author)

Descriptors :   (*CRACK PROPAGATION, METALS), (*FATIGUE(MECHANICS), METALS), STRESSES, FRACTURE(MECHANICS), ALUMINUM ALLOYS, STEEL

Subject Categories : Metallurgy and Metallography
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE