Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase II | Award Amount: 959.48K | Year: 2014
Advanced composite material systems are vital to the development of lightweight, multi-functional Army missile systems. In addition to reducing the weight of the structure, composite materials provide the ability to expand the function of the structure by tailoring stiffness and strength characteristics for numerous applications such as solid rocket motor cases, missile airframes, missile guidance housings, as well as many launch tubes and launcher primary structures. The AMRDEC Weapons Development and Integration Directorate has identified a need to understand the operational fitness of such structures following impact events from a wide range of energy levels. The objective of the proposed Phase II research program is to develop and demonstrate an analysis tool that allows designers to evaluate post impact residual strength of composite structures. A user element (UEL) subroutine for use with commercially available analysis codes is proposed. A new shell element that offers advantages in both the economy and reliability of computations is to be demonstrated. This approach will link the UEL subroutine to a nonlinear material model to evaluate progressive damage and a shear correction model that accurately predicts the transverse response of impacted composite structures. Concurrently, material characterization and database development will be conducted to support implementation.
Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase I | Award Amount: 99.99K | Year: 2014
Missile modernization and future missile designs are utilizing more sophisticated and higher powered electronics in the pursuit of extended missile range, improved accuracy and precision targeting for striking enemy threats. Tight packaging and sophistication of these electronic systems can generate significant heat loads, which needs to be dissipated efficiently in order to maintain functionality and survivability. This program proposes to develop a cost-effective composite airframe with integrated, interlaminar heat spreaders that will provide high in-plane conductivity for thermal management without structural degradation. To seek a balance among cost, thermal capabilities, and structural properties, the program will perform trade studies among commercially available heat spreaders (e.g., flexible graphite sheets currently being employed in cell phone and laptop industry) as well as explore hybrid pitch-pan fabrics, spread tow carbon nanotube composite sheets, and metalized coated carbon fabrics. In addition to material evaluation, this program will evaluate design and processing methodologies to efficiently integrate the heat spreader into airframe type composite structures with minimal retrofitting of current fabrication procedures (e.g., filament winding). This research will directly support the Army"s need for improved thermal management to protect high value, sensitive guidance and control electronics.
Agency: Department of Defense | Branch: Navy | Program: SBIR | Phase: Phase I | Award Amount: 79.98K | Year: 2014
Efficient use of two-dimensional (2D) and three-dimensional (3D) woven carbon-carbon (C/C) composite materials used in many thermal protection applications requires that onset and development of material non-linearity be accounted for during design. The theoretical framework and computational infrastructure to implement nonlinear material models into the finite element analysis code ABAQUS exists at Materials Sciences Corporation (MSC), including both stress-based and/or fracture-based failure analysis methods. Post-damage onset material response in the stress- or strain based ply level composite failure modeling approach is approximated as piece-wise linear and the continuum level response for the fiber bundle and woven composite is defined analytically based on homogenization theory. The fracture-based approach is referred to as the discrete damage space homogenization method, or DDSHM, since the damage state within a representative volume element is discretely modeled. The DDSHM approach can also calculate, directly and in a theoretically rigorous manner, changes in thermal expansion coefficients and thermal conductivity as damage evolves, which may be important for C/C materials. The link between constituent material properties, micro-structural features and measured response will be established under this program thus providing a path to a validated micromechanics modeling approach that can be used to support thermal protection component design.
Materials Sciences Corporation and University of Kentucky | Date: 2013-05-31
A carbon nanotube studded carbon fiber tow and matrix prepreg includes a body comprising a tow of surface fibers and interior bulk fibers. The surface fibers are studded with carbon nanotubes and the carbon fibers are infiltrated with a matrix material.
Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase I | Award Amount: 98.80K | Year: 2015
Guidance and navigation components within missile systems are vulnerable to performance degradation as a result of vibrations generated by neighboring components. Conventional methods to alleviate this degradation include installing passive vibration-damping materials or adding additional material to shift resonance frequencies. Both of these approaches add parasitic weight to the system. With recent advances in additive manufacturing technologies, components and structures that can benefit from cellular design and optimization are now being realized. Materials Sciences Corporation (MSC) will team with the University of Pittsburgh (PITT) to develop analysis tools for determining cellular architectures, frequency based topology optimization codes that make use of cellular architectures, and design tools to develop cellular structures. The overall objective of the Phase I effort will be to demonstrate the proposed cellular optimization procedure via analysis and validate by experiment.