GRAIN SIZE DEPENDENCE OF FRACTURE OF ALPHA-COPPER ALUMINIUM ALLOYS IN MERCURY.
Abstract
Polycrystalline specimens of alpha-phase copper-aluminum alloys of varying composition, amalgamated with mercury, have been deformed in tension in a soft tensile machine. In all cases, brittle intergranular failure occurred at stresses and strains below those required for fracture in air, the degree of embrittlement increasing with increasing aluminum content. The alloys having stacking fault energies less than 8 ergs/sq cm were found to obey the Petch-Stroh relation. The other alloys showed negative deviations from this relation, particularly for large grain sizes, which became more marked with increasing stacking fault energy. Values of the fracture energy have been obtained for all the alloys; they vary from 48 ergs/sq cm for pure copper, to 470 ergs/sq cm for Cu-8 wt.% Al. These values are only applicable for relatively small grain sizes. A model is proposed to explain the deviation from the Petch-Stroh relation in the high-stacking-fault-energy alloys. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1966
- Accession Number
- AD0481871
Entities
People
- F. W. J. Pargeter
- M. B. Ives
Organizations
- McMaster University