Accession Number : AD0713536

Title :   ANISOTROPY OF FATIGUE CRACK PROPAGATION IN HOT ROLLED BANDED STEEL PLATE,

Corporate Author : WATERVLIET ARSENAL N Y

Personal Author(s) : Heiser,Francis A.

Report Date : 1970

Pagination or Media Count : 15

Abstract : The dependence of crack growth rate on stress intensity factor was found to be sensitive to the microstructural constituents, their orientation with respect to the fracture plane and direction, and the level of the stress intensity factor. The anisotropy of crack growth rate was found to be a function of the level of the stress intensity factor. Macroscopi growth rate could be considered to be the summation of several fracture mechanisms, the most important being striation formation and local fracture of brittle microconstituents, viz., inclusion-matrix fracture or cleavage. Striation spacing was seen to be independent of orientation suggesting that fracture of inclusions was responsible for the crack growth rate anisotropy. This indicated that steel cleanliness should be more important in low cycle fatigue applications. The dependence of crack growth rate on stress intensity factor decreased as the toughness of the base material increased. In general, those factors which contributed to high fracture energy also contributed to low fatigue crack growth rate, particularly at the higher values of K. (Author)

Descriptors :   (*STEEL, CRACK PROPAGATION), METAL PLATES, ANISOTROPY, FATIGUE(MECHANICS), STRESSES

Subject Categories : Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE