Patent ID: 7109139

Claim:
A process for the manufacture of dense neodymium stabilized β-Si 3 N 4 -α-SiAlON composite, which process comprises: preparing a homogeneous powdered mixture essentially consisting of: 49 to 63 mole % Si 3 N 4 , 2.5 to 3.5 mole % Al 2 O 3 , 29 to 43 mole % AlN, 2.1 to 2.9 mole % SiO 2 and 3.1 to 4.9 mole % Nd 2 O 3 , mixed in proportion to make a total of 100 mole to obtain a mixed powdered batch, passing the powdered batch through 100 mesh followed by drying, pressing to form green compacts, and subjecting the green compacts to sintering to obtain the dense neodymium stabilized β-Si 3 N 4 -α-SiAlON composite.