Brittle fracture in iridium

Journal Article · Fri Mar 31 23:00:00 EST 1978 · Metall. Trans., A; (United States)

DOI:https://doi.org/10.1007/BF02646403· OSTI ID:6517648

Hecker, S S ^[1]; Rohr, D L; Stein, D F

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1. Los Alamos Scientific Lab., NM

Brittle fracture in fcc metals is uncommon. It is not common knowledge that single crystals or iridium, a high melting point fcc metal, fail by brittle cleavage at room temperature. Furthermore, polycrystalline iridium fails predominantly by brittle intergranular fracture at temperatures below 1000/sup 0/C. With the aid of several models of brittle fracture we have demonstrated that cleavage in iridium is intrinsic, resulting from apparently very strong and directed atomic binding forces. Intergranular fracture in iridium has been generally assumed to arise from the segregation of harmful impurities to the grain boundaries. It was demonstrated using Auger electron spectroscopy that impurity segregation to grain boundaries in iridium was not necessary for grain boundary fracture to occur, thereby demonstrating that intergranular brittle fracture in polycrystalline iridium is also intrinsic and not impurity related.

• OSTI ID: 6517648
• Journal Information: Metall. Trans., A; (United States), Journal Name: Metall. Trans., A; (United States) Vol. 9:4; ISSN MTTAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ALLOYS
BRITTLENESS
CLEAVAGE
CRYSTAL STRUCTURE
ELEMENTS
FAILURES
FRACTURES
GRAIN BOUNDARIES
IRIDIUM
IRIDIUM ALLOYS
MECHANICAL PROPERTIES
METALLURGICAL EFFECTS
METALS
MICROSTRUCTURE
PLATINUM METAL ALLOYS
PLATINUM METALS
REFRACTORY METALS
TRANSITION ELEMENTS
TUNGSTEN
TUNGSTEN ADDITIONS
TUNGSTEN ALLOYS