RU1830057C RU1830057C SU4203283A RU1830057C RU 1830057 C RU1830057 C RU 1830057C SU 4203283 A SU4203283 A SU 4203283A RU 1830057 C RU1830057 C RU 1830057C Authority RU Grant status Grant Patent type Prior art keywords process producing polycrystalline composite material Prior art date 1986 09 16