Tantalum alloys containing up to 30 per cent tungsten were suc-ce8s£ully arc-melted as 3-1/2 inch diameter ingots and fabricated to rod and sheet bar using conventional techniques.nAlloys containing up to 20 per cent tungsten were ductile at room temperature in the annealed condition. Tungsten additions increased the hardness of tantalum at 1200 *C to a maximum at about 50 per cont tungsten. The Ta-10W alloy was found to have physical properties, ductility and weldability similar to pure tantalum, with, about three times the tensile strength of pure tantalum at 3500 P.nCarbide thicknesses in the range 1 to 60 mils were obtained by carburizing tantalum and tantalum-tungsten alloys in the range 2000 to 2500 C. Carburizing temperature was the important variable affecting carbide thickness. Tungsten additions resulted in a change in the morphology and relative quantities and distribution of the carbide 'phases.nExperimental rocket nozzle firings showed tungsten additions significantly improved the performance of tantalum and carburizing resulted in further improvement. Limitations of various carburized and uncarburized alloys as rocket nozzle materials were established. The carburized Ta-10W alloy had the optimum combination of fabricability, ductility and erosion resistance for nozzle applications.
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