METHOD OF MAKING HIGH-PURITY VACUUM-SEALED FOIL FROM BERYLLIUM Russian patent published in 2013 - IPC B21B1/40 B82Y40/00 

FIELD: process engineering.

SUBSTANCE: invention aims at producing high-purity vacuum-sealed foil with fine-grained structure from nanocrystalline beryllium and at increasing the yield. Proposed method comprises wrapping the workpiece in steel jacket 20, its sealing, multipass rolling with intermediate heating at 650-900°C, cooling down and jacket removal. Said billet represents a nanocrystalline beryllium. After every intermediate heating the billet is held in furnaces > 5 min. After rolling the billet is cooled at the rate of ≤10°C/min, said jacket being removed by etching and foil surface is finished.

EFFECT: high chemical purity and mechanical properties of vacuum-sealed film.

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