Tungsten's refractory or high-temperature properties are relatively unimportant in heavy alloy applications. They would come into play during manufacture, but the addition of nickel and/or other alloying elements make it possible to carry out liquid-phase sintering at relatively low temperatures. Two W/NiFe alloys were chosen for this investigation, with 83 and 93 weight percent of tungsten and the remainder NiFe in a 7:3 ratio. The ratio between nickel and iron was chosen to avoid intermetallics. The tungsten powder was initially rod milled for 1 h, using pure tungsten rods and an inert argon atmosphere to prevent oxidation. Elemental powders were combined to give the desired composition, with 0.5 percent Acrawax pressing lubricant, then blended in a Turbula mixer for 20 min to ensure homogeneity.
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