69493 - Matrix Crack Networks in Sicf/sic Composites:in-Situ Characterisation and Metrics
Ceramic matrix composites (CMCs) offer potential for high temperature engineering applications under circumstances where the temperature capabilities of conventional metals are exceeded. To support future employment of these materials, thorough mechanical characterisation to gain an understanding of their associated damge and failure mechanisms must be performed across a wide range of representative temperatures.
The present paper will report ongoing research to characterise the initiation of matrix cracking at room temperature under tensile stress and subsequent damage development under fatigue loading in a SiCf/SiC composite. Imaging and mechanical property data were obtained via in-situ loading within a scanning electron microscope and X-ray tomography facility. This enabled 2D surface inspections of cracking and correlation to full 3D through thickness damage networks. The temporal nature of damage development was also recorded through the selective employment of acoustic emission.
Metrics to describe the spatial distribution of cracks, crack lengths and crack opening displacement under load will be presented. The inspections also provided detailed evidence of the associated crack closure phenomena.
The understanding of matrix crack saturation and matrix/fibre interfacial mechanics will be explored, together with the implications for the use of X-ray tomographic inspection of engineering components during service.
Keywords: in-situ loading; X-ray tomogrpahy; fatigue; crack networks.
Matrix Crack Networks in Sicf/sic Composites:in-Situ Characterisation and Metrics
Paper Type
2020 Technical Publication
Description
Session: 02-01: Mechanical Behavior of Ceramics & CMCs-I
Paper Number: 69493
Start Time: June 8th, 2021, 09:45 AM
Presenting Author: Spencer Jeffs
Authors: Steven Jordan Swansea University
Spencer Jeffs Swansea University
Christopher Newton Swansea University
Louise Gale Rolls-Royce plc
Pascual NicholsonTWI Technology Centre Wales
Martin Bache Swansea University