PNNL

Abstract

Apart from increase in failure strength, increase in the impact resistance is one of the major reasons for the interest in long-fiber polymer composites for automotive structural applications. The in-house code EMTA has been adapted to accommodate dynamic problems. It combines with ABAQUS Explicit solver to model impact behavior of long-fiber thermoplastics. At the present stage, the model captures the elastic behavior of LFTs in a dynamic formulation that incorporates the Eshelby equivalent inclusion method, the Mori-Tanaka assumption and the fiber orientation averaging technique. The effect of average fiber length on the impact behavior of discontinuous fiber composites has been studied with the aid of the preliminary model. Fiber lengths from short fiber range to long fiber range were explored with fiber orientation distributions from obtained from previous studies. The numerical examples indicate a slight improvement in the energy absorption capabilities of long fiber thermoplastics over short fiber thermoplastics. Advanced impact models need to be incorporated into the current code to model impact behavior with greater accuracy.