Research Topic: New/Emerging Advanced Material Technologies

Standardization of Analytical and Experimental Methods for Crashworthiness Energy Absorption of Composite Materials

The proposed research will develop a set of standardized procedures for the experimental and numerical characterization of the crush behavior of composite materials. Recent findings have identified the key factors preventing the introduction of polymer composites in primary crash structures as the lack of adequate design guidelines, accurate simulation tools, specialized test methods for energy absorption, and an available material database. The proposed research plans to address all of these factors in a uniquely integrated fashion. Initially the research aims to develop a test standard with which to characterize the Specific Energy Absorption (SEA), featuring a corrugated web coupon. The results using this specimen will be compared systematically against the values measured using a flat plate specimen with dedicated anti-buckling fixture, C-channels, and square tubes using identical material and processing conditions. The method will then be used as benchmark to compare the accuracy of material models and progressive failure criteria within mainstream commercially available finite element codes (LS-DYNA, ABAQUS Explicit and possibly PAM-CRASH). This unified and integrated investigation will be used to generate a set of accessible numerical guidelines for the industry to build on. Lastly, the standard will be used to generate design guidelines and to systematically characterize the material systems and forms. This effort provides direct support to the current standardization efforts of CMH-17 (former MIL-HDBK-17) and will aim to result in a test method for standardization by ASTM Committee D30.

Certification of Discontinuous Composite Material Forms for Aircraft Structures

Discontinuous Fiber Composites (DFCs) represent a viable solution for the cost-effective design of secondary structures and components for aeronautical applications. One of the challenging hindering the widespread use of these materials is the limited understanding of the effect of the manufacturing process and platelet size on the mechanical performance. The goal of this project is to fill this knowledge gap by performing a comprehensive set of experimental characterizations and numerical simulations devoted to a thorough investigation on structural performances of DFCs. We aim to characterize the main failure mechanisms and develop a physically-based computational modeling of DFCs. The findings of this study will contribute to the safety and certification of DFC structures.