EFFECT OF STRAIN-RATE ON THE FRACTURE OF CERAMIC FIBER-REINFORCED GLASS MATRIX COMPOSITES

The effect of strain rate on the fracture behaviour of two ceramic fib re reinforced glass matrix composites was studied. Increasing the stra in rate was found to enhance catastrophic failure in both of these com posites. This was attributed to the crack deflection and changes in th e fibre pullout length as a function of strain rate. Enhanced strain r ates were found to decrease the strength, static toughness and fractur e energy of the composites. This effect was more pronounced in the cas e of the coated fibre composites as compared to the uncoated fibre com posites. This is because of fibre/matrix isolation, obtained as a resu lt of the coating.