Single-Crystal YAG Reinforcement Preforms for Refractory Composites

Preforms (essentially, shaped mats) of single-crystal yttrium aluminum garnet (YAG) fibers can now be readily fabricated in net size and shape, with tailored orientation of the fibers. These preforms can be used as fiber reinforcements in ceramic- and metal-matrix composite materials that withstand temperatures as high as 1,700 °C. The development of these preforms and composites is a continuing effort in conjunction with other efforts to develop lightweight components for aircraft turbine engines.