| As the principal raw materials of cemented carbide, abundances of elementalcobalt(Co) and tungsten(W) are0.0025%and0.00015%in Continental crust,respectively. Not only absolute amount is little, but their yield distribution is veryunbalance. So the residual natural resources are depleted day by day. Hence, since thecemented carbide came out, the regenerative issue has always be concerned by theexperts in the industry. The research of the reclaimed cemented carbide is veryimportant to take advantage of the natural resources effectively and to develop thecircular economy. The core goals of this task are to take full advantage of renewableresources, to solve the insufficient resource of W、Co and to reduce the cost ofproduction of cemented carbide.The effects of different wet-grinding time、sintering process and Y2O3content onmicrostructure and properties of the reclaimed cemented carbide were investigated inthe paper. The microstructure, physical and mechanical properties were analyzed bymeans of XRD, TEM, SEM, EDS, Rockwell hardness and bending strength tester etc,optimized the preparation technology of reclaimed cemented carbide and prepared thereclaimed cemented carbide with excellent whole performance.The research results showed that the whole performance of reclaimed cementedcarbide were the best with the pressure sintering, at temperature of1723K andwet-grinding36h. The density, HRA, average bending strength, Co-%magnetismand coercive force of reclaimed cemented carbide were14.71g/cm3,90.1,3560MPa,7.2%,15.8KA/m, respectively. The grains of reclaimed cemented carbide added0.4%Y2O3were fine and uniform, and the cemented carbide had preferable wholeperformance. However, the microstructure of reclaimed cemented carbide added1.5%Y2O3was with serious defects, such as coarse WC grains, pore and holes.Excessive Y2O3introduced a new defect, such as localized aggregation and inclusionof Y2O3so on, the whole performance of cemented carbide decreased heavily. |
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