In automotive industry, polypropylene-based materials are generally used in the manufacturing of car bumpers. In such a case, a detailed study of strain rate and temperature sensitivities of PP-based composites is essential since the bumpers undergo compressive loading in a wide range of temperatures. In this study, PP based composites with ethylene octane copolymer (EOC) and talc were prepared by melt processing. Viscoelastic properties of the considered materials were characterized by dynamic mechanical analysis. The quasi-static tensile testing was done with a universal testing Instron machine whereas the dynamic behavior was investigated by using split Hopkinson pressure bars. For the dynamic testing, the investigated strain rate ranged from 5.9×102 s-1 à 3.3×103 s-1 and the investigated temperature ranged from -30°C to 85 °C. The results showed that the considered materials are strain-rate and temperature sensitive. The addition of EOC decreased the yield strength and Young's modulus of PP whereas the presence of talc fillers increased the Young's modulus of PP. For PP and PP/talc composites, the results showed an impact induced brittleness, especially at low temperature. However, for PP/EOC and PP/EOC/Talc composites, the impact-induced failure was less significant.
- Dynamic behavior
- Ethylene octane copolymer
- Split Hopkinson pressure bars
ASJC Scopus subject areas
- Materials Science(all)