Papers by Keyword: SiC Reinforcements

Abstract: Discontinuously reinforced cast metal-matrix composites are increasingly attracting the attention of aerospace, automotive and consumer goods industries. In this study, SiC particle reinforced aluminium alloy is selected to produce metal matrix composites (MMC) using different of parameters blade angle and stirring speed and composition of SiC reinforcement. Mechanical test, metallographic analysis and fracture analysis will be conducted to investigate mechanical properties of material and to observe particle distribution of SiC reinforcement and fracture properties respectively with varies angles and stirring speed of impellers and different composition of SiC reinforcement. Metallographic analysis on composition records at low speed, there exist a particle collection and gas existence on the specimen. At blade angles of 300, increasing on stirring speed and composition of SiC reinforcement may result better of particle distribution. For mechanical test, different composition of SiC reinforcement, blade angle and stirring speed will be affecting a mechanical property of material. The result of the experiment showed at blade angle 300, stirring speed 100rpm and 10% composition of SiC reinforcement give better result of hardness, ultimate strength, energy absorption, microstructure and fracture of composite. For this study, it proved that at the lower blade angle and the increment on stirring speed and composition of SiC reinforcement give a better result on particle distribution of SiC reinforcement, fracture and mechanical properties for A1-MMC.

Abstract: The aim of this paper is to investigate the behaviour in terms of drilling forces and roughness of Metal Matrix Composites (MMC) in hot drilling machining. In particular, Al2009/(SiC)_w, Al6061/(SiC)_w, and Al6061(Al₂O₃)_p metal matrix composites were used, and the adopted temperature were in the range 20°C-160°C. A comparison with drilling at room temperature has been discussed. The results have shown the sensible influence of the working temperature on drilling forces and on surface material properties. In the case of Al2009/(SiC)_w a minimum in the drilling forces has been found, making possible the dry machining and improving the cutting conditions. Instead, for Al6061/(SiC)_W and Al6061(Al₂O₃)_p in the used temperature range no minimum appears.

Abstract: The experiments on ultraprecision turning of SiC reinforced aluminium composites have been done by using polycrystalloid diamond (PCD) tool with the three-dimensional cutting forces measured with a Kistler dynamometer, the quality of the machined surfaces was examined under Atom Force Microscope (AFM) and Scanning Electron Microscope (SEM) and the roughness of the machined surfaces was measured with roughometer of Talysurf-6. The experimental results show that the quality of the machined surfaces of SiC reinforced aluminium composites is predominantly controlled by the deformation mechanisms of SiC reinforcements, and the quality of the machined surfaces is better when reinforcements deform in the form of direct cutoff than in the form of pullout. The higher the volume fraction of SiC reinforcements, the worse the quality of the machined surfaces and the greater the amplitude of vibration and the average value of the cutting forces. On the same condition of volume fraction and cutting, the quality of the machined surfaces of SiC whiskers reinforced aluminium matrix composites is better than that of SiC particles reinforced aluminium matrix composites.