The impact properties of copper, copper-10 nickel, and a superalloy matrix reinforced with tungsten fibers were studied. In most cases, the following increased composite impact strength: increased fiber or matrix toughness, decreased fiber-matrix reaction, increased test temperature, hot working and heat treatment. Notch sensitivity was reduced by increasing fiber or matrix toughness. The effect of fiber content depended on the relative toughness of the fibers and matrix. Above 530 K a 60 volume percent superalloy matrix composite had a greater impact strength than a turbine blade superalloy, whereas below 530 K a hot worked 56 volume percent composite had a greater impact strength than the superalloy.