Non-Linear Damage Model for Carbon-Carbon Composite Design
Navy SBIR FY2014.1

Sol No.: Navy SBIR FY2014.1
Topic No.: N141-082
Topic Title: Non-Linear Damage Model for Carbon-Carbon Composite Design
Proposal No.: N141-082-0883
Firm: GoHypersonic Inc.
714 E. Monument Ave
Suite 119
Dayton, Ohio 45402-1382
Contact: Zachary Gaston
Phone: (937) 531-6678
Web Site:
Abstract: Currently, difficulties in modeling non-linear behavior and damage modes of carbon-carbon (C/C) composites beyond simplified in-plane models prevent accurate assessment of bending load and thermal stress effects in interlaminar directions where the stress limits can be significantly lower than in-plane stress limits. To this end, the proposed Phase I SBIR program seeks to develop and refine a new feature for ABAQUS/Standard, using user defined subroutines, for improved modeling of non-linear behavior of C/C composites from limited material characterization data, develop missing data from empirical relationships and micromechanical models, consider multiple modes of damage beyond the standard in-plane damage modes to include interlaminar damage and incorporate aspects of thermal damage. These tools will be validated using published experimental data. Following the success of the Phase I program objectives, GHI will develop a Phase II plan which will enable the goal of experimentally validating and refining this new C/C composite modeling tool. Based on our previous experiences and our current computational and experimental capabilities, the goals set forth in this proposal are well within our abilities. More importantly, this work will be of great benefit to the Navy and to the future of C/C composite analysis and hypersonic flight as a whole.
Benefits: At the end of a successful Phase I and Phase II program, the GHI team will possess a well-validated, robust analysis method and skillset for thermo-mechanical design and analysis, improving upon existing capabilities for C/C composite design. These capabilities will allow us to improve on existing concepts and develop new and innovative flight hardware that is capable of high thermal loading, lightweight, durable and no longer over-conservative to compensate for unknowns. In addition, the Phase I and Phase II program will generate a much broader understanding of C/C composite behavior and brittle material damage modes, which we believe is crucial to the future of our modeling capabilities. Our growing competency of C/C composite modeling will be relevant to both the US government (DoD and NASA) and industry to design hypersonic vehicle structures. GHI intends to work with Dassault SystŠmes (ABAQUS developers) to become a development partner and market this capability as a standard feature in future release of ABAQUS. In addition to the tools created, the technology developed in this program will allow us to extend our understanding of composite material behavior to ceramic matrix composites and the curing/pyrolysis/densification steps during composite manufacturing processes. Understanding the stresses and strains that form in a composite lay-up as the components cure and go through the necessary pyrolysis/densification steps will be invaluable to composite manufactures, helping to adjust lay-up tool design and prevent large discrepancies in the part geometry between manufacturing steps, which will result in fewer slips in schedule and cost as components will hold the expected tolerance with improved confidence.