Advantages of SiC Hi‐Nicalon or NLM 202 Fibers in SiC_f–SiBC Composites

Abstract

SiC f -SiBC composites were produced using NLM 202 and Hi-Nicalon SiC f fibers. Tensile creep tests were performed under a reduced pressure of argon. These composites show a good creep resistance at 1473 K with a strain rate ranging from 10 À9 to 10 À7 s À1 , depending on the stress level. The creep strength was improved by using Hi-Nicalon instead of NLM 202 SiC f fibers, to the extent of increasing the loadability by 50 MPa at the same operating temperature or increasing the temperature by 50 K for the same load. The damage observed in SEM micrographs and the use of the damage mechanics provide evidence that creep is governed by a damage-creep mechanism in two steps.

Tensile creep and rupture of 2D-woven SiC/SiC composites for high temperature applications

“…8,9 Therefore, the purpose of this study was to compare the creep and rupture properties of different SiC fiber-reinforced SiC matrix composites with a view to the effects of the two major constituents, i.e., the fiber and the matrix. Some tensile creep studies have been performed on high-content CVI SiC [10][11][12][13] and PIP SiC 14 matrices for composites with lower temperature polymer-derived SiC-based fiber-types. This study will focus on composites reinforced with more creep-resistant fibers.…”