Cracks Near Interfaces in Composites: A Focus on Optical Materials with Graded Microstructures

摘要

The ultimate goal of the research is to develop a fundamental understanding of crack growth near interfaces in optically transparent materials. Transparent magnesium aluminate spinel and a class of transparent glass ceramics were chosen because of their ability to allow systematic variation of the residual stress at interfaces. Once processing conditions are established, crack extension studies will be conducted to examine the crack path stability for cracks situated near interfaces and/or high residual stress gradients. Analytical modeling on the influence of higher order terms on the crack tip stress field has begun; results will be discussed at a later time.