Accession Number : AD0664174

Title :   THE MECHANICS OF CRACK ARREST IN MILD STEEL.

Descriptive Note : Technical rept.,

Corporate Author : STANFORD UNIV CALIF DEPT OF MATERIALS SCIENCE

Personal Author(s) : Wilshaw,T. R. ; Harris,D. O.

Report Date : NOV 1967

Pagination or Media Count : 16

Abstract : Dynamic K sub IC values for mild steel were measured using instrumented impact bend tests containing fatigued notches and compared with the stress intensity values in a Robertson crack arrest test. It is proposed that crack arrest occurs by the initial slowing down of the crack due to increased temperature which leads to a dramatic deceleration due to the large strain-rate sensitivity of the material. When the strain rate at the crack tip is maintained by dynamic loading which causes forced crack propagation, the crack will remain brittle to much higher temperatures than the crack arrest temperature. (Author)

Descriptors :   (*STEEL, MECHANICAL PROPERTIES), (*CRACK PROPAGATION, MECHANICS), STRAIN(MECHANICS), IMPACT TESTS, FRACTURE(MECHANICS), TEMPERATURE, DEFORMATION, TOUGHNESS, STRESSES, TENSILE PROPERTIES, PLASTIC PROPERTIES, INTENSITY, PHOTOGRAPHS, SENSITIVITY, NITROGEN

Subject Categories : Metallurgy and Metallography
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE