Session: 03-08-02: Micromechanics and Multiscale Modeling II

Paper Number: 110366

110366 - Comparisons Between In-Situ Micro-Scale Transverse Compression Experiments and Modeling Methods of Numerical Finite Elements and Semi-Analytical Micromechanics 

Composite materials are critical for the continued advancement of aerospace applications due to its versatility and structural integrity in extreme environments. Full characterization of composite materials requires understanding its mechanical behavior from a multi-scale perspective, including analyses from the atomic, molecular, micro, meso, and macro scales. Experimental data is necessary to benchmark and validate the engineering tools used to establish this multi-scale material behavior. This study highlights a method to bridge the gap between experimental and model validation of composite materials at the micro scale. A novel, in-situ, microscale transverse compression experiment recently conducted at the Air Force Research Laboratory (AFRL) used digital image correlation (DIC) to generate local strain data of four unidirectional carbon-fiber polymer matrix composites. This type of data acquisition allows for a one-to-one comparison to microscale models that was previously not attainable. Experimental effective properties and strain field data in the elastic region is compared with the semi-analytical micromechanical methods of the Generalized Method of Cells (GMC) and High-Fidelity Generalized Method of Cells (HFGMC) used in the NASA Glenn Research Center tool, NASMAT, as well as a finite element (FE) model. Findings from this study shows that current microscale model capabilities can predict effective properties with less than 15% margin of error, identify similar and contrasting localized strain fields of the composite microstructure within each method, and highlight NASMAT’s higher computational efficiency when compared to its FE counterpart.

Presenting Author: Emily Zeitunian The Aerospace Corporation

Presenting Author Biography: Emily Zeitunian is currently a Launch Structures Member of Technical Staff at the Aerospace Corporation in El Segundo, CA. Prior to this position, she attended Michigan Technological University and obtained her Master's degree under the advisory of Dr. Gregory Odegard. She studied Mechanical Engineering and centered her thesis work around a collaborative effort between Evan Pineda of NASA Glenn Research Center and Mark Flores of the Air Force Research Laboratory in validating semi-analytical micromechanical composite theories with novel, in-situ experimental results.

Authors:

Emily Zeitunian The Aerospace Corporation
Ivan Gallegos Michigan Technological University
Evan Pineda NASA Glenn Research Center
Mark Flores Air Force Research Laboratory
Gregory Odegard Michigan Technological University