Crack Growth by Concentrated Plastic Flow.
Final rept. 1 May 72-31 Oct 75,
MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF MECHANICAL ENGINEERING
Pagination or Media Count:
A criterion that test specimens be large enough for valid fracture prediction from J sub Ic tests appears to be that the stress at the half-ligament dimension, calculated from J sub Ic and the Hutchinson-Rice-Rosengren singularity, be no more than 1.05 to 1.1 times the yield strength. For smaller specimens, the J-integral varied linearly with ligament size and was surprisingly similar for single and double grooved specimens. On the other hand, fully plastic triaxiality was shown to be very important in welded plates of A-36 steel, in which the transition temperature for brittle crack propagation was raised 40 K above the Charpy value by the triaxiality due to simulated cracks on both sides of the plate. This may also be of interest in fragmentation.
- Metallurgy and Metallography