Multi-length Scale Material Model Development for Armorgrade Composites

Abstract

The present work was focused on establishing microstructure/property relationships in p-phenylene terephthalamide (PPTA) based materials and structures. A multi-length-scale computational approach has been developed in order to identify and quantify the contribution of various microstructural features and processes, at different lengthscales, to the macroscopic-level ballistic-penetration resistance of PPTA-based fabric or PPTA-fiber-reinforced polymer-matrix composites. Specifically, the role of various material-synthesis-/fiber-processing-induced defects, as well as defects induced during the weaving process, was investigated. The results obtained clearly revealed that The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggesstions for reducing this burden, ABSTRACT Multi-length Scale Material Model Development for Armor-grade Composites Report TitleThe present work was focused on establishing microstructure/property relationships in p-phenylene terephthalamide (PPTA) based materials and structures. A multi-length-scale computational approach has been developed in order to identify and quantify the contribution of various microstructural features and processes, at different length-scales, to the macroscopic-level ballistic-penetration resistance of PPTA-based fabric or PPTA-fiber-reinforced polymer-matrix composites. Specifically, the role of various material-synthesis-/fiber-processing-induced defects, as well as defects induced during the weaving process, was investigated. The results obtained clearly revealed that both the static mechanical material properties such as stiffness and strength, and the dynamic-impact properties such as V50, are affected by the type and the concentration of various defects. Lastly, it was demonstrated that in order to construct a high-fidelity continuum-level PPTA-based material constitutive model, the role of the material microstructure (including defects) at different length-scales must be taken into account. (a) Papers published in peer-reviewed journals (N/A for none)Enter List of papers submitted or published that acknowledge ARO support from the start of the project to the date of this printing. List the papers, including journal references, in the following categories:

Multi-scale simulation methods of mechanical properties of organic ballistic fibers and their composites: a review

“…The continuous material model for fibre-reinforced composites established by Yen is updated using the mesoscopic molecular level [21] and the effects of various morphological flaws on the mechanical properties of PPTA fibrils/fibres/yarns. The response of the material is significantly affected by the combination of microstructural effects under quasi-static, simple mechanical test settings and under dynamic ballistic conditions, according to simulation results utilizing the improved PPTA material model.…”

“…The molecular chain scale[1], the microfiber scale[21], the fiber scale[23], the yarn scale[24], the fabric unit scale[25], the single-layer laminate scale[28], the laminate scale[29], and the laminate scale[30] were all taken into account by M. Grujicic[6] et almulti-scale . 's simulation approach.…”