AN INVESTIGATION OF TENSILE PROPERTIES AND A SIMPLE CONSTITUTIVE MODEL FOR A RANDOM CONTINUOUS FIBER THERMOPLASTIC COMPOSITE

The tensile properties of a commercially available, random continuous- fiber thermoplastic composite material are investigated at various str ain rates and elevated temperatures. The material utilizes polypropyle ne (PP) for the matrix material, with random continuous E-glass fiber reinforcement. Tensile modulus, tensile strength, strain to peak stres s, and strain energy are experimentally determined at strain rates var ying from 0.000167 sec(-1) to 0.0334 sec(-1) and temperatures varying from 20 to 120 degrees C. The material properties are found to have la rge scatter caused by local variations in fiber content and orientatio n. The tensile properties are independent of the strain rate but depen d on the temperature. A model for the material response based on a sim ple power law equation is presented.