Polymer-filler derived Mo2C ceramics

Manufacturing, microstructure and properties of novel reaction bonded Mo2C materials derived from polymer/reactive filler mixtures were investigated. Mo powder was used as a filler to react with carbon bearing decomposition products of poly(methyl- and phenysiloxanes) during pyrolysis in nitrogen atmosphere. Microcrystalline composites with the filler reaction products Mo3C, Mo,Si, Mo,Si, embedded in a silicon oxycarbide glass matrix could be formed with complex geometry owing to near net shape polymer/ceramic conversion. Depending on the precursor composition and pyrolysis conditions, ceramic hard materials with a density up to 97% theoretical density, a hardness of 10 GPa, a Young's Modulus of 250 GPa, a fracture toughness of 5 MPam(1/2) and a flexural strength of 330 MPa were obtained. (C) 1999 Elsevier Science S.A. All rights reserved.