Fatigue and Creep Behaviour of a SiCf/SiC Composite for Nuclear Fusion Reactor Applications
This study presents the results of mechanical tests of commercial 2D SiCf/SiC ceramic matrix composite for fusion reactors applications. The creep behaviour was investigated by means of flexural constant load stress-rupture tests, in controlled atmosphere at 600 and 1000°C. The creep strain and time to failure vary with applied load according to a power law. Cyclical tests at room temperature and at high temperature showed that the material has a good fatigue behaviour at room temperature, as no evident fatigue damage was detected after 80.000 cycles at a peak load up to 98 % of MOR. Conversely at high temperature (1000°C) the specimens showed a progressive compliance increase and limited cycles to failure even at peak load as low as 40 % of MOR. Creep phenomena seem to influence the fatigue behaviour. Creep strain analysis, crack growth and fracture surface observations allowed to investigate the mechanisms that affect the crack propagation, the fracture process and the rupture life under cyclic loading and under constant stress loading at different temperatures.
E. Trentini et al., "Fatigue and Creep Behaviour of a SiCf/SiC Composite for Nuclear Fusion Reactor Applications", Advances in Science and Technology, Vol. 45, pp. 1444-1449, 2006