The use of extra-fine nickel powders significantly reduced nickel dusting in binder-treated mixes to levels as low as the nickel dusting levels in diffusion-alloyed mixes. TRS and tensile properties of the two binder-treated mixes were superior to those of their diffusion-alloyed counterparts. The binder-treated mix containing extra-fine nickel powder showed the largest improvements. TRS was 5 percent to 10 percent higher than that of the diffusion-alloyed mix while UTS and yield stress were 15 percent to 20 percent higher. Increased densification occurred in the binder-treated mix containing extra-fine nickel powder. As density increased, this shrinkage effect also increased and the density after sintering of the binder-treated mix containing extra-fine nickel powder was higher than of the diffusion-alloyed mix and the binder-treated mix containing the standard nickel powder. DC measurements indicate that, in addition to being more negative, DC is more consistent in the fine-nickel mix. NRAs were more evenly distributed and less concentrated in nickel in the microstructure of the fine-nickel powder mix compared with the diffusion-alloyed mix. As a result, the copper distribution was improved in the microstructure of the fine-nickel powder mix.
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