Irradiation of dilute Cu-W alloys with 1.8 MeV Kr+ between 300 K and 573 K is found to induce nucleation of a high density of W nano-precipitates. HRTEM and aberration-corrected STEM reveal that the ∼3 nm precipitates have a preferred orientation relationship with the matrix. A variant of the Bain relationship exists with preferred alignment occurring along Cu〈2 2 0〉|| W〈010〉, with small angular differences amongst the particles, which is compensated by interfacial dislocations or strain. The formation mechanism for such an orientation relationship is rationalized on the basis that small W clusters form within the local melt of an energetic displacements cascade, resulting in the partial alignment of the nanoprecipitates with the Cu lattice as the Cu solidifies.
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Materials Science(all)
- Nuclear Energy and Engineering