NANO-CRYSTAL SINTERED BODIES ON BASE OF ALPHA-OXIDE OF ALUMINIUM, METHOD OF THEIR FABRICATION AND IMPLEMENTATION Russian patent published in 2010 - IPC C22C1/05 C04B35/10 B82B1/00 

FIELD: metallurgy.

SUBSTANCE: sintered body contains 95-100 wt % of Al₂O₃, has relative density ≥97%, Vickers hardness HV_0.2≥17.2 GPa and crystal structure with average dimension of primary crystals Al₂O₃ <100 nm. A sintered body is fabricated by compacting nano-crystal powder α-Al₂O₃ with average diametre of particles ≤100 nm produced out of base aluminium tri-chloride with chemical formula Al₂(OH)_nCl_z, also n is a number between 2.5 and 5.5, z is number between 3.5 and 0.5, and sum n+z is constantly equal to 6, producing compaction of ≥60% density and sintering at 1200-1500°C.

EFFECT: produced abrasive grains facilitate increased efficiency of grinding.

30 cl, 3 dwg, 2 tbl, 6 ex