Accession Number : AD0282479

Title :   LOW TEMPERATURE FATIGUE CRACKS AS DELIBERATE FRACTURE ORIGINS.

Descriptive Note : Interim rept.,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON D C

Personal Author(s) : Stawley ,J. E. ; Lupton,T. C.

Report Date : 26 JUL 1962

Pagination or Media Count : 8

Abstract : Specimens of 1/16 in. thick sheet of a high strength steel were provided with small surface cracks by fatigue stressing either at room temperature or at -22 F. The specimens were then tested in tension to evaluate the effective-apparent K sub Ic plane strain crack toughness values. The cracks formed at -200 F gave rather less consistent results and somewhat higher average apparent K sub Ic values at room temperature and at -100 F than did those formed at room temperature. It was also observed that the progress of fatigue cracking was more erratic at the lower temperature. (Author)

Descriptors :   *FRACTURE(MECHANICS), *STEEL, HEAT TREATMENT, METALLURGY, SHEETS, STRESSES, TENSILE PROPERTIES, TOOL STEEL

Distribution Statement : APPROVED FOR PUBLIC RELEASE