Residual stress state and damage mechanisms in ceramic matrix composites inferred from uniaxial tests incorporating unloading and reloading sequences
The mechanical response under uniaxial loading of two bidirectionally reinforced ceramic matrix composites is studied at room and elevated temperatures. The thermal expansion mismatch between fibres and matrix is of opposite sign in the two composites, resulting in vastly different mechanical behaviour. A careful examination of the stress-strain curves with unloading-reloading cycles at room and elevated temperatures yields qualitative and semi-quantitative information on a number of factors governing the mechanical response of the composite such as the residual stress state, the amount of frictional sliding along the fibre matrix interface, and the accumulation of damage in the form of interfacial debonding, matrix microcracking and fibre failure. A mastercurve unifying the stress-strain behaviour for different specimens at different temperatures is presented, and implications for damage assessment are outlined.
Bibliographic Reference: Paper presented: 4th European Ceramic Society Conference, Riccione (IT), October, 1995
Availability: Available from (1) as Paper EN 39186 ORA
Record Number: 199511349 / Last updated on: 1995-10-31
Original language: en
Available languages: en