Micro-mechanical analysis of unidirectional composites.

摘要

This dissertation presents a study on various aspects of micro-mechanics based analysis of unidirectional composite materials. Attempt is made to fill the deficiencies in the existing literature. A simple, square cells type micro-mechanical model similar to those widely used by other researchers is compared with a more advanced micro-mechanical model. Experimental studies were performed on laminae, laminates and cylinders made from carbon epoxy composites. It was realized that the effects of physical phenomena such as presence of residual stresses and matrix micro-cracking is critical for any practical use of micro-mechanical models. A smeared cracking approach was used to characterize the micro-cracking in matrix. Experimental comparisons show that the accurate micromechanical model with proper partial cracking options provides good bounds on experimental response with consistent accuracy. A square cells type model however is not consistent in its predictions, thus raising questions about its applicability in any general micro-mechanics based analysis.