Executive Summary
This master's thesis investigates the ballistic performance of hybrid alumina/composite shields for military aircraft using finite element simulations. It compares carbon fiber reinforced polymer (CFRP) and ultra-high molecular weight polyethylene (UHMWPE) as backing materials. The study found that UHMWPE offers superior energy absorption and stopping capability at higher velocities, while CFRP performs better against lower velocity threats with less deformation.
Why It Matters
This document is crucial for defense analysts and engineers as it provides detailed insights into the design and ballistic performance of advanced lightweight armor for military aircraft, directly impacting survivability and operational capabilities.
Key Takeaways
- Hybrid alumina/composite shields are simulated for ballistic response in military aircraft, comparing CFRP and UHMWPE backings.
Source evidence · PDF page 117
This dissertation investigated the ballistic response of hybrid alumina/composite targets through explicit finite element simulations in Abaqus/Explicit. The ceramic strike face was described using the JH-2 model, while the composite backings were modelled with a 3D Hashin formulation implemented in a VUMAT, combined with cohesive interfaces for CFRP and tied interfaces for the UHMWPE laminate.
- CFRP backings effectively stop projectiles at 400 m/s but are perforated at 600 m/s, showing limited failure strain.
Source evidence · PDF page 117
In the case of CFRP, the projectile was arrested at 400 m/s, with the absorbed energy reaching a plateau of approximately 900 J after an interaction time of about 150 µs. At 600 m/s, however, the laminate was perforated, and the absorbed energy exceeded 1800 J without stabilising, reflecting the residual velocity of the projectile.
- UHMWPE backings successfully stop projectiles at both 400 m/s and 600 m/s, demonstrating superior energy absorption but with greater deformation.
Source evidence · PDF page 117
For the UHMWPE backing, the projectile was stopped at both 400 m/s and 600 m/s. The absorbed energy reached approximately 900 J at 400 m/s and close to 1900 J at 600 m/s, with clear plateaus in both cases, indicating complete energy dissipation.
Strategic Relevance
The research directly contributes to the development of next-generation lightweight ballistic protection systems for military aircraft, enhancing survivability against various threats. Understanding the trade-offs between different composite materials is vital for optimizing aircraft design and operational effectiveness.