Tungsten based, functionally graded composites were formed using vacuum plasma spray consolidation methods. The composites consisted of tungsten-hafnium and in some cases, combined with molybdenum, tantalum and/or titanium powders. The powders were mixed or co-sprayed as monolithic blends nad vacuum plasma spray depostied onto cylindrical tungsten substrates to porduce high density refractory metal clad rods. Additional evaluations of deposits which were sprayed in alternating layers to achieve microlaminates. The clad composite structures with tungsten cores were produced to cause a desired localized deformation behavior upon high energy impact. processing cosisted of blending and feeding powders, plasma spray forming hte thick claddings onto a W-core, thermal and HIP trreatment followed by final machining to dimensions. The influence of processing variables and powder compositions were investigated. The effect of these variations on microstructure, compressive strength and high energy impact deformation was evaluated and is reported here. The porject goal has been to develop a flexible proessing technique for porducing layered and monolithic refractory metal composites.
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