Volume 14, Issue 4, 2005

PIP Preparation of silica FIBRE fabric reinforced silicon nitride-based composites using polyhydridomethylsilazane

Gong-jin Qi, Chang-rui Zhang, Hai-feng Hu, Chang-cheng Zhou

State Key Lab of Advanced Ceramic Fibres & Composites, College of Aerospace & Materials Engineering,
National University of Defense Technology,
Changsha 410073, P.R.China E-mail:qgjin@tom.com (Gong-jin Qi)

(Received 7/05; accepted 10/05)

Abstract
A new type of composites, three-dimensional silica fibre fabric reinforced silicon nitride-based composites, were prepared by PIP method through repeated infiltration of polyhydridomethylsilazane and pyrolysis at 773-873K in ammonia atmosphere. The density of the composites reached 1.66g/cm3 after four PIP cycles, and the flexural strength was 56.3 MPa. The composites showed a near-brittle fracture mode without long fibre pull-out in the fracture surface. It was the relatively strong fibre/matrix interface bonding that led to the moderate mechanical property.