Processing and Properties of Reaction Bonded Silicon Nitride Made from Laser Synthesized Silicon Powders

Abstract
Laser synthesized silicon powders have been used to make reaction bonded silicon nitride samples. Maximum hardness (11.3 GNm−2), fracture toughness (3.6 MNm−3/2), pore size (Hg porosimetry 50–300Å radius) and strength (∼460 MNm−2) values reflect the superior microstructures that are observed. With anaerobic anhydrous processing, these powders nitride to completion in less than 7 hours at 1400°C.