Session: 05-11-01: Multifunctional Composites and Structures: Mechanics, Modeling, and Space Applications

Paper Number: 150468

150468 - Design of Composites With Ultra-High Modulus and Zero Coefficient of Thermal Expansion With a Defect-Aware Computational Design Framework 

Maintaining dimensional stability over extreme temperature variations is of prime importance for the design of next-generation space telescopes. The backplane structure that supports the mirror of these telescopes needs to satisfy the dual requirement of ultra-high (>275 GPa) structural stiffness and ultra-low (1-100 ppb/K) coefficient of thermal expansion (CTE). Carbon fiber reinforced polymer (CFRP) composites are desirable candidates for designing a material with high stiffness and ultra-low CTE while maintaining a high stiffness-to-weight ratio because of their maturing material fabrication and applications in space technologies. These ambitious requirements can potentially be achieved by overcoming property conflicts through the tailored material design parameters: the choice of fiber and matrix properties, the volume fraction (V_f) and orientation of fiber (θ_f), and the fiber layup.  Even though both CTE and stiffness requirements can be achieved analytically, the uncertainties in material parameters and manufacturing defects pose a major hindrance to realizing the tight CTE requirement. To incorporate these uncertainties, we propose a hierarchical composite design framework with Monte Carlo simulation: the randomness of the material and manufacturing parameters are incorporated to determine composite properties at the first level and the randomness in the composite properties is utilized to determine the stiffness and CTE in the next hierarchy. This hierarchical approach accounts for the stochasticity associated with fibers and matrix properties by expanding the lamina level analysis into the laminate level analysis. Furthermore, we determine the sensitivity of these properties to each input parameter, i.e., material and manufacturing parameters, through a variance-based global sensitivity analysis using Sobol’s Method. This sensitivity index reveals that the manufacturing parameters (V_f and θ_f) have the highest impact on the property control. Although the randomness in manufacturing conditions can be reduced, to design a thermally stable composite, we need a computational framework which is aware of the defects and their uncertainties. This defect-aware framework will introduce a correction factor, which shows the difference between CTEs calculated through laminate theory and estimated utilizing hierarchical Monte Carlo Simulations. We anticipate that our detailed stochastic computational framework will lay the foundation for defect-aware high modulus and ultra-low CTE composite design. With the advancement of material innovation and fabrication, superior constituents can be utilized in future, which will ensure less uncertainty in the outcome. Furthermore, with future sophisticated space missions planned such as NASA’s Habitable Worlds Observatory and Far-Infrared Great Observatory, the defect-aware framework can help to design the supporting structures of these space telescopes.

Presenting Author: Paranjoy Basak University of Wisconsin-Madison

Presenting Author Biography: Paranjoy Basak is a second-year PhD Student in Mechanical Engineering at the University of Wisconsin-Madison. Currently, he is working on next-generation composites with aerospace applications with Dr. Ramathasan Thevamaran at Thevamaran Lab. He did his Bachelors in Mechanical Engineering from R V College of Engineering, Bangalore and Masters in Aerospace Engineering from Indian Institute of Technology, Kanpur. Besides researching he enjoys reading Bengali novels and cooking.

Authors:

Paranjoy Basak University of Wisconsin-Madison
Yasara Dharmadasa University of Wisconsin-Madison
Lavanya Raman University of Wisconsin-Madison
Ramathasan Thevamaran University of Wisconsin-Madison