Interaction of radiation damage with strain field around α-precipitates in electron-irradiated β-Nb-Zr alloys

The strain field around α-precipitates (hcp) in the β-Nb-Zr phase has been evaluated to study its relaxation mechanism during electron irradiation in a high voltage electron microscope. The crystallography of the α-precipitates is determined to be of Burgers' orientation relationship with the β-phase. The compressive strain field around the α-precipitates is detected and determined by use of the strain contrast of electron microscopy and the elastic continuum theory. The relaxation process of the strain field around the α-precipitates is observed during electron irradiation, and is analyzed in terms of accumulation of vacancies. (orig.)