Accession Number:

ADA056723

Title:

Crack Growth by Concentrated Plastic Flow.

Descriptive Note:

Final rept. 1 May 72-31 Oct 75,

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF MECHANICAL ENGINEERING

Personal Author(s):

• McClintock,Frank A.

Report Date:

1978-06-28

Pagination or Media Count:

29.0

Abstract:

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.

Descriptors:

• *STEEL
• *CRACK PROPAGATION
• *PLASTIC PROPERTIES
• ALUMINUM ALLOYS
• FRACTURE(MECHANICS)
• BOUNDARIES
• TRANSITION TEMPERATURE
• HOLES(OPENINGS)
• DUCTILITY
• INTEGRAL EQUATIONS
• NOTCH TOUGHNESS
• TRIAXIAL STRESSES

Subject Categories:

• Metallurgy and Metallography
• Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE