Summary: | 碩士 === 華梵大學 === 機電工程學系博碩專班 === 100 === ABSTRACT
The purpose of the paper investigated the bond properties of the porous metal wheel. The bond was mainly based on bronze matrix and different pore formers, which were mixed with alumina or diamond grits to sinter to the desired samples under hot press. The following analyses of these sintered samples were studied: (1) porosity and density, (2) hardness, (3) bending strength and rupture strain, (4) microstructure, and (5) observation of the fracture structure.
The experiment results showed that the bronze matrix containing the different pore formers would obtain the variations of porosity, density, hardness and bending strength. Adding non-organic pore former to the bond showed a relatively larger hardness and bending strength. This may be because non-organic pore former is a reductant with the removal oxidized metal surface, which causes among the metal powders to form a better binding. The bond containing an organic pore former also can obtain a relatively higher hardness and bending strength. Finally, when a better pore former was selected to fabricate a porous metal bond wheel sample, a relatively good hardness and bending strength of wheel was obtained. Besides, the smaller amount of porosity produced for the wheel sample caused a relatively higher hardness and bending strength. The hardness and bending strength of the porous metal bond decreased with an increase sintering temperature, but porosity increased. This possibly is because the metal powders grow and soften to produce plastic deformation to extrude out from the graphite mold.
Keywords: Porous metal bond, Pore former, Porosity, Hardness, Bending strength.
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