Effect of ageing treatments at High temperatures on the microstructure and mechanical behaviour of 2D Nicalon/C/SiC composites. 1: ageing under vacuum or argon

摘要

Two-dimensional Nicalon/C/SiC composites processed by chemical vapour infiltration have been aged at 1100-1500 deg.C under vacuum or argon. The composites experience a weight loss Δm/m_0 related to the decom- position of the SiO_2xC_1-x phase of the fibres and to side-reactions between the fibre decomposition gaseous products (particularly SiO) and carbon (from the fibre and the interphase), as assessed by electron probe microanalysis, and auger electron sectro- scopy analyses.