Brittle fracture in iridium
- 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), Vol. 9:4
- Country of Publication:
- United States
- Language:
- English
Similar Records
Brittle fracture in polycrystalline Ir-0. 3 pct W
Brittle fracture and grain boundary chemistry of microalloyed NiAl
Related Subjects
IRIDIUM
CLEAVAGE
FRACTURES
GRAIN BOUNDARIES
IRIDIUM ALLOYS
TUNGSTEN
METALLURGICAL EFFECTS
BRITTLENESS
TUNGSTEN ADDITIONS
ALLOYS
CRYSTAL STRUCTURE
ELEMENTS
FAILURES
MECHANICAL PROPERTIES
METALS
MICROSTRUCTURE
PLATINUM METAL ALLOYS
PLATINUM METALS
REFRACTORY METALS
TRANSITION ELEMENTS
TUNGSTEN ALLOYS
360102* - Metals & Alloys- Structure & Phase Studies