Characterization of Fracture Toughness of Hybrid MMCs the Short Fiber Reinforced Metal Matrix Composites

Abstract

Evaluation of fracture toughness of short fiber reinforced metal matrix composites (MMCs) becomes important for the application as structural materials. Therefore, in this study static and dynamic fracture toughness of MMCs manufactured by squeeze casting process were investigated. A number of MMCs have been tested with various matrix alloys, volume fractions, and specifically types of reinforcements. It was found that static and dynamic fracture toughness of metal matrix composites was remarkably decreased by the addition of ceramic reinforcements. Dynamic fracture toughness slightly decreased compared with static fracture toughness because of the effect of dynamic velocity under impact loading. The toughness of ceramic reinforced MMCs is controlled by a complexity interaction between the matrix alloy and reinforcement. Important properties which influence toughness include the type of reinforcement (its physical form, size), volume fraction and combination of reinforcement, and the matrix alloy. And notch fracture toughness of MMCs for simple evaluation was also discussed.