The influence of grinding process on the mechanical behavior of SiC/SiC composite tubes under uniaxial tension

SiC/SiC composites are candidates of interest for fuel cladding applications in pressurized light-water reactors. In this study, fuel cladding tubes were made by filament winding and the matrix was deposited by CVI (Chemical Vapour Infiltration), which results in surface irregularities and waviness defects. This paper examines the influence of grinding steps on the mechanical behavior of tube specimens. Different depths of inner and outer surface grinding are carried out from a reference grade. Cyclic tensile tests are then performed. Elastic behavior analysis shows that the machining of tubes does not cause pre-damage. Analysis of unload-reload cycles indicates that the internal slippage does not depend on the seal coat thickness and that the surface quality weakly influences damage in the loading direction. Damage in the shear plane and ultimate failure strength strongly depend on the inner seal coat thickness.