Fracture toughness variations of injection molded long fiber reinforced thermoplastics

The fracture toughness, defined as K-c , of injection molded long fiber rei nforced polypropylene with 50% E-glass and its variations is investigated. Rectangular plaques of different thicknesses at various sets of processing conditions have been fabricated. In order to assess the spatial variation o f the fracture toughness, specimens aligned in the direction of the injecti on molding flow and perpendicular to it, have been obtained and tested at p re-selected locations. The morphology of the samples consisting of flow ind uced through-thickness layers was also evaluated experimentally and related to the fracture toughness, thus showing the effect of the part morphology on such mechanical property.