Study of alloy strengthening due to atomic order. Final report, May 1, 1969-April 30, 1983

Technical Report · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5999838

Marcinkowski, M J

Ordered alloys show a high work hardening rate and enormous strengthening, owing to a large increase in dislocation density within the alloys. These alloys are mostly brittle, with the brittleness often being confined to the grain boundaries. It was found that any distortion could be described in terms of a continuous array of surface dislocations of infinitesimal strength. By using the surface dislocation concept, the theory of fracture could cover the entire range from fully brittle to fully ductile crack nucleation and propagation. It was shown that all grain boundaries are composed of lattice dislocations, but that much of their stress fields is annulled due to surface dislocations. The brittle behavior of ordered alloys can be attributed to the grain boundaries providing a high-energy path for crack propagation. (DLC)

• Research Organization: Maryland Univ., College Park (USA). Dept. of Mechanical Engineering
• DOE Contract Number: AS05-76ER03935
• OSTI ID: 5999838
• Report Number(s): DOE/ER/03935-92; ORO-3935-92; ON: DE85010338
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
656000 -- Condensed Matter Physics
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOYS
BRITTLENESS
CRACK PROPAGATION
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DISLOCATIONS
FRACTURE PROPERTIES
HARDENING
LINE DEFECTS
MECHANICAL PROPERTIES
ORDER-DISORDER TRANSFORMATIONS
PHASE TRANSFORMATIONS
RESEARCH PROGRAMS
STRAIN HARDENING