Features of plastic stran under rolling of beryllium foil

Processes of beryllium fracture under cold rolling and defect healing under annealing were judged by change in density defect determined by the method of triple hydrostatic weighing. Technically pure beryllium hot deformed in a case of stainless steel was used as initial material. It is sown that technically pure beryllium can be attributed to the aging alloys due to rather limited solubility of other elements in it. Presence of excess phase and unsoluble BaO and Be2C inclusions results in instability of hardening under cold rolling brought about, probably, by channeling of plastic strain followed by fracture of undissolved particles. Beryllium aging under annealing affects heat recovery due to which recrystallization of cold-rolled beryllium proceeds only at 800-850 deg C (0.7-0.73 tsub(m.)) at the mentioned content of impurities. Due to the fact that the vacancy character of microvoid healing is independent of excess and hardening phases, density defect annealing proceeds at temperatures of 0.45-0.55 tsub(mel.)