Estimation of Elastic Constants Using Numerical Methods and Their Validation Through Experimental Results for Unidirectional Carbon/Carbon Composite Materials

The need for materials for high-temperature applications has always been a topic of research for various engineering applications. The need for materials for high-temperature applications is an important need specifically for defense and space applications where they are subjected to very high temperatures during reentry into the earth's atmosphere. Carbon/Carbon composites are promising materials for various fields of engineering. These materials are increasingly opted for due to their ability to withstand high temperatures above 3000 & DEG;C. Engineering designers have an important role in designing the components and sub-systems using these materials for high-temperature applications. Prediction of elastic constants for these materials is a significant step in the design of the components. The current work is aimed at the prediction of elastic constants. Elastic constants of unidirectional carbon/carbon composites are predicted in this work. Unit cell models of unidirectional carbon/carbon composites containing random positioning of fibers were created. Elastic constants were evaluated by applying periodic boundary conditions. The carbon/carbon test samples were fabricated to validate the predicted elastic constants. The PAN-based carbon fiber with carbon matrix was used for the fabrication of unidirectional carbon/carbon test samples. The uncertainty of measurement for the experiments was estimated using guide to the expression of uncertainty of measurement. The predicted values of elastic constants agree closely with the experimental results.