The Effect of Ball Milling Process on Sintering and Densification Enhancement of W-Bronze Composites
DOI:
https://doi.org/10.11113/jt.v59.2578Keywords:
Metal matrix composites, mechanical alloying, sintering, microstructure, scanning electron microscopyAbstract
Τhe miscibility of W in Sn and Cu is extremely poor. The wettability of W by those two elements is limited. To tackle this problem, two step ball milling process of the W–bronze elemental powders was proposed in this study. The softness of Sn in the first step was exploited to modify the surface morphology of the W particles. In the second step Cu was added to the ball milled mixture. To achieve this goal, two different sets of W50wt. %–pre mix bronze compacts of ball milled and of as received powders were utilized. Sintering process was performed at 1150°C. The two–step ball milled powders yielded sintered compacts of fine polygonal and homogeneous W network skeletal dispersed in bronze matrix. Sintered compacts of about 95% theoretical density were produced by this technique.References
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