Experimental and Numerical Investigations of Textile Hybrid Composites Subjected to Low Velocity Impact Loadings

Gautam S Chandekar,Ajit D Kelkar

doi:10.1155/2014/325783

Abstract

In the present study experimental and numerical investigations were carried out to predict the low velocity impact response of four symmetric configurations: 10 ply E Glass, 10 ply AS4 Carbon, and two Hybrid combinations with 1 and 2 outer plies of E Glass and 8 and 6 inner plies of Carbon. All numerical investigations were performed using commercial finite element software, LS-DYNA. The test coupons were manufactured using the low cost Heated Vacuum Assisted Resin Transfer Molding (H-VARTM©) technique. Low velocity impact testing was carried out using an Instron Dynatup 8250 impact testing machine. Standard 6 × 6 Boeing fixture was used for all impact experiments. Impact experiments were performed over progressive damage, that is, from incipient damage till complete failure of the laminate in six successive impact energy levels for each configuration. The simulation results for the impact loading were compared with the experimental results. For both nonhybrid configurations, it was observed that the simulated results were in good agreement with the experimental results, whereas, for hybrid configurations, the simulated impact response was softer than the experimental response. Maximum impact load carrying capacity was also compared for all four configurations based on their areal density. It was observed that Hybrid262 configuration has superior impact load to areal density ratio.

Highlights

Optimization of laminated composites for their desired impact properties has been a major challenge faced by today’s composite design world owing to the fact of keeping pace with the rapid advancements in technology and engineering
The impact on glass reinforced polymers (GRP) using energy model is presented in [9], whereas in [10] the authors have proposed an analytical approach for simulation of low velocity impact using linearized contact law
The simulated impact load is plotted against the experimental impact load over the range of progressive damage that is at six impact experiments from incipient damage through complete failure

Summary

Introduction

Optimization of laminated composites for their desired impact properties has been a major challenge faced by today’s composite design world owing to the fact of keeping pace with the rapid advancements in technology and engineering. In their paper [2], the authors simulate the ballistic impact on composite laminates, whereas Hosur et al [3] have experimentally investigated the low velocity impact response to different hybrid configurations. Elder et al [24] in their research paper compared various de-lamination predictive models such as the linear elastic fracture mechanics model This was used extensively where the damaged shape of the de-lamination can be predicted and a suitable mesh can be used. The impact on glass reinforced polymers (GRP) using energy model is presented in [9], whereas in [10] the authors have proposed an analytical approach for simulation of low velocity impact using linearized contact law. Low velocity impact on composite sandwich panels using an assumed strain solid element approach and classical mechanics approach was studied in [15, 16], respectively. In research papers [17, 18]

H-VARTM Manufacturing

Modeling and Property Evaluation

Impact Testing

Results and Discussion

Conclusion

Disclosure