Microstructure inheritance of matrixes of SiCf/Ti6242 composites from precursor wire coatings by α plus β phase field consolidation

SiCf/Ti composite owns the attractive advantages of lightweight and excellent high-temperature performance, which make it have great significance to the development of aerospace industry. However, the complicated fabrication route and novel architecture of SiCf/Ti composite bring about more difficulties for controlling its microstructure. In this work, the method of regulating the structure and performance of the composite matrix by adjusting the characteristics of the precursor wire was explored. The physical vapor deposition (PVD) method was applied to fabricate precursor wires. Ti6242 coatings with bamboo leaf-shaped grains and chrysanthemum-shaped grains were deposited on SiC fibers by changing the PVD condition. It is found that the original structure of the Ti6242 coating of precursor wire has significant impact on the microstructure of the composite matrix after hot iso-static pressing (HIP). The matrix transformed from the Ti6242 coating with bamboo leaf-shaped grains exhibits equiaxed grain structure. While the other matrix has a columnar crystal structure, and the inside of the columnar crystal inherits the original chrysanthemum-shaped structure. The columnar crystal matrix has lower hardness and modulus than the equiaxed grain matrix.