Preparing damage-tolerant titanium-matrix composites

Abstract

In-situ TiB-reinforced titanium alloy composites have been produced by both rapid solidification and ingot metallurgy techniques. The reinforcements have been shown to result in strength and modulus improvements, improved fracture toughness, increased fatigue endurance limit, and better fatigue crack growth and creep resistance than conventional monolithic titanium alloys. In addition to improved mechanical properties, in-situ composite structures and components with complex shapes can be fabricated using conventional ingot metallurgy, near-net shape forming techniques. ACKNOWLEDGEMENTS Research described here was funded by the McDonnell Douglas Independent Research and Development program and by the OhioAerospace Institute. Appreciation is also extended to J.D. Keyes, J.J. Evans, and DI Deuser for assistance with experimental/ processing techniques.

Deformation and fracture properties of damage tolerant in-situ titanium matrix composites

“…The rapid solidification processing of Ti-B (boron) alloys with concurrent large undercooling and high cooling rates was found to be very effective for the production of in-situ titanium matrix composites which contain large volume fractions of the reinforcing phase, similar to the whisker-reinforced aluminum alloy metal matrix composites [28][29][30][31]. The resultant RSP alloys have excellent compositional homogeneity, small grain sizes and a near homogeneous distribution of the reinforcing phase.…”