Vacancy Source in Nearly Perfect Crystals

抄録

Vacancy generation process in nearly perfect aluminum single crystals was investigated by X-ray diffraction topography technique of Lang. A lot of small black dots were observed in the topograph taken after the temperature rise from room temperature to 200°C, and these dots are confirmed to be small interstitial type dislocation loops. It was concluded that the thermal generation process of vacancies in nearly perfect crystals consists of the following two steps. Small interstitial clusters are formed in the perfect lattice first, and then these grow to interstitial type dislocation loops emitting vacancies into lattice.