Experimental and numerical investigations of strain rate effects on mechanical properties of LGFRP composite

Long Glass Fiber Reinforced polypropylene composite (LGFRP) has been increasingly used in automotive components regarding its advantages of mechanical properties and flexible design features. Automotive structural components could sustain various crash environments and be loaded in different strain rates. Hence, the objective of the current study is to investigate the influences of strain rates on mechanical properties of LGFRP composite by both experimental tests and numerical simulations for its application on automobile structural components. First, LGFRP composite specimens were prepared by hot compression molding, and were tested by universal testing machine with various strain rates ranging from 0.001 s−1 to 50 s−1. A continuous digital image correlation tensile test was implemented to provide more detailed information for numerical analysis. Then, corresponding finite element simulations were established according to the experimental test conditions for in-depth investigation on strain rate effects for the future application in automotive components. Both experimental and simulation results show that LGFRP composite is sensitive to strain rates, and its ultimate strains and ultimate strength incline with increasing strain rates.