Papers by Keyword: Particle Reinforced Aluminum Matrix Composite

Abstract: High-speed milling tests were performed on SiC_p/2009Al composites in the speed range of 600-1200m/min using PCD tools to investigate the cutting temperatures and the influence factors. The results showed that the cutting temperature could reach 580°C under the given cutting conditions. Graphitization took place on the PCD tools under the high cutting temperature coupled with the effects of abrasive wear of SiC particles and catalysis of copper in the 2009 aluminum matrix. Cutting parameters, tool materials, workpiece materials and tool wear condition had significant effect on the high speed milling temperature while tool geometries had the minor effect. Among these influence factors, cutting speed was the most significant factor. Reinforcement volume fraction was the less significant factor and followed by radial depth of cut, feed rate and tool materials.

Abstract: High speed milling tests were performed on the SiCp/2009Al composites to investigate the cutting forces by using PCD tools in the speed range of 600-1200m/min. The results showed that the peak value of the cutting force Fy (in the tool radial direction) was in the range of 700-1450N under the present cutting condition. The maximum amplitude of cutting force vibration in the tool radial direction can reach 700N. Cutting forces increased with increasing feed rate or radial depth of cut and decreased with increasing cutting speed. Negative rake angle and relatively large tool nose radius were recommended as far as cutting forces was concerned. Materials with higher volume fraction or smaller reinforcement particle size had the bigger cutting forces. T6 heat treatment can increase the cutting forces significantly but the using of coolant can decrease the cutting forces evidently.

Abstract: Tool life and tool wear, cutting forces and cutting temperature, surface finish, chip formation and surface generation were investigated when milling SiC_p/2009Al composites at the cutting speed of 1200m/min using PCD tools. The results showed that PCD tool life was 150min when the 0.1mm tool wear criterion was chosen. PCD tool mainly suffered from tool grain breaking-off, chipping, abrasive wear, micro cracks and adhesive wear due to he very high-frequency impact and scrape of SiC particles. The peak value of the cutting force Fy (the radial direction) was over 1300N and the cutting vibration was very severe. The cutting temperature was 523.7°C. Pits, voids, matrix tearing and scratch were the main defects on the machined surface. The deformation layer thickness was about 20-35μm. The chip for the vol.20%SiC_p/2009Al composite took the form of flow type and the mechanisms of the chip formation were the combination of dynamic behavior of voids/micro-cracks and adiabatic shear. For the vol.35%SiC_p/2009Al composite, the chip was non-continuous and had the tendency of saw-toothed type. Material swelling and side flow, tool-workpiece relative vibration, feed rate and tool nose radius, removal mode of SiC particles were the main mechanisms of surface generation.

Abstract: The wear pattern and its mechanisms of Single Crystal Diamond (SCD) tool has been investigated experimentally and theoretically during ultra-precision turning of SiC particle-reinforced aluminum matrix composite. The results showed that micro wear, chipping, peeling, abrasive wear and chemical wear were the dominating wear patterns of SCD tools. Coupled with XRD analysis on the machined surface and Raman studies on the flank wear land of SCD tool, it was pointed that the combined effects of abrasive wear of SiC particles and catalysis of copper in the aluminum matrix have caused the severe graphitization.