Model and test validation of stress-strain for needled C/SiC composites

The stress-strain behavior for needled C/SiC composites was studied under static tensile loading at room temperature. A unit-cell model to predict the stress-strain properties for needled C/SiC composites was presented based on the representative volume element which was chosen according to the microstructure by micro CT technology reconstruction. Based on the interfacial friction model which is capable of stress-strain calculation of unidirectional fiber reinforced C/SiC composites under arbitrary loading/unloading procedure, the stress-strain response of unidirectional fiber bundle layer can be calculated from the properties of material mesoscopic constituents. By substituting the stress-strain response of unidirectional fiber bundle layer into the unit-cell model, the stress-strain response of the entire needled C/SiC composites can be obtained by finite element methods. By performing static tensile test of needled C/SiC composites, the predicted stress-strain responses match well with the test results.