Orthorhombic Titanium Aluminide Metal Matrix Composites (O TMS's) - A review

摘要

Continuous silicon carbide (SiC) reinforced titanium matrix composites (TMCs) utilizing matrices based upon the intermetallic orthorhombic (O) phase, Ti(2)AlNb, have been the subject of a significant development activity over the past several years. These O TMCs are considered enabling materials for rotating engine components in order to meet the requisite increased thrust/weight ratios and decreased specific fuel consumption targets for the next generation of advanced propulsion systems being developed under the Air Force IHPTET (Integrated High Performance Turbine Engine Technology) initiative. The O-based class of titanium aluminides has demonstrated significant advantages as a matrix for continuous reinforcement for use at temperatures up to 700 degrees C compared to their alpha-2 (a(2)) Ti(3)Al and conventional titanium matrix predecessors. Amongst these advantages and increased elevated temperature strength and creep resistance, improved ambient temperature fracture resistance, and decreased reactivity with SiC reinforcing fibers. Additionally, O TMCs, have met or exceeded most generic performance requirements for hoop wound engine hardware such as bladed rings (blings) or bladed disks (blisks). The subject review summarized significant findings for the numerous research activities undertaken in the development and evaluation of this important class of TMCs.