scholarly journals Effect of porosity on the nonlinear and time-dependent behavior of Ceramic Matrix Composites

2020 ◽  
Vol 184 ◽  
pp. 107658 ◽  
Author(s):  
Unni Santhosh ◽  
Jalees Ahmad ◽  
Greg Ojard ◽  
Imelda Smyth ◽  
Yasser Gowayed ◽  
...  
Keyword(s):  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Time Dependent ◽  
Matrix Composites ◽  
Dependent Behavior

scholarly journals Time and Cycle Dependence in High Temperature Fatigue of Ceramic Matrix Composites

1996 ◽  
Author(s):  
Marc Steen ◽  
José-Lorenzo Vallés
Keyword(s):  
High Temperature ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Fatigue Behaviour ◽  
Time Dependent ◽  
Matrix Composites ◽  
Fibre Failure ◽  
High Temperature Fatigue ◽  
Stress Ratios ◽  
Cyclic Damage

The high temperature fatigue behaviour of two 2D reinforced ceramic matrix composites (CMCs) Is studied under high vacuum conditions. The mechanical loads imposed result in matrix cracking upon first loading, so that continued cyclic loading results in progressive interfacial debonding and/or matrix crack multiplication, as well as fibre failure. In order to investigate whether the fatigue life is mainly governed by time-dependent creep or by cyclically induced fatigue damage, a range of frequencies and two stress ratios are explored in stress controlled fatigue tests. The results obtained indicate that under pulsating fatigue (positive stress ratios or tension-tension) the material response is affected by both creep and fatigue mechanisms. The cyclic damage component gains in relative importance with increasing test frequency. Under reversed loading conditions (negative stress ratios), and depending on the creep strength mismatch between the fibres and the matrix, the time-dependent damage component can be largely suppressed, and the composite fatigue behaviour can become close to purely cycle-dependent. In both cases and for both composites fatigue failure is triggered by fibre failure.

The role of oxidation in time-dependent response of ceramic–matrix composites

2015 ◽  
Vol 76 ◽  
pp. 20-30 ◽  
Author(s):  
Y. Gowayed ◽  
E. Abouzeida ◽  
I. Smyth ◽  
G. Ojard ◽  
J. Ahmad ◽  
...  
Keyword(s):  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Time Dependent ◽  
Matrix Composites
Sign in / Sign up

Export Citation Format

Share Document