عنوان مقاله [English]
Tungsten carbides are used in cutting blades and other similar items because of their high hardness. In this study, tungsten carbide (WC) powder and cobalt (Co) powder in size of less than 10 microns and weight ratio of 94% tungsten carbide and 6% cobalt (WC-6% Co) were mixed together in a high-energy mechanical milling. Then they milled in various ratios of ball to powder and time. Milled samples were studied using scanning electron microscopy (SEM). The results obtained were compared by microscopy and EDX elemental analysis. Optimized powder for the production of powder metallurgy sample was selected and sintered. Metallography and hardness testing and SEM imaging was performed on sintered sample. The results showed a significant improvement in grain size to reach below 100 nm in the milled powders and in the sintered samples were reaching below 150 nm. Vickers hardness in the final sample reached in 1752.
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