Papers by Keyword: SiC/Cu Composite

Abstract: A porous SiC ceramic reinforced copper-matrix composite was fabricated by spontaneous infiltration of molten Cu-24at%Si alloy into the reinforcement. The influence of process parameters on the infiltration behavior and microstructure of the as-prepared SiC/Cu composite investigations showed that infiltration temperature had an important influence on the infiltration behavior, and higher infiltration temperature which decreased the viscosity of molten Cu-24Si was beneficial to the penetration. Besides, the degree of infiltration increased with the increase of dwelling time at 1600°C. SiC particles were bonded together by sintering additives to form the porous reinforcement, which can be maintained after spontaneous infiltration. The interfacial bond between SiC and Cu-24Si alloy was tight, and no obvious interfacial reaction layer was observed in the as-prepared composite.

Abstract: A three dimensional (3D) SiC/Cu-Si composite with bicontinuous structure was fabricated by spontaneous infiltration method, using porous recrystallized SiC ceramic with porosity of 37% as 3D network reinforcement and Cu alloy (Cu-18Si) as matrix. The phase composition, microstructure, and thermo-physical properties of the as-prepared 3D-SiC/Cu-Si composite were investigated. The experimental results showed that the Cu-18Si alloy could fully penetrate into the porous SiC ceramic at 1600 °C for 2 h spontaneously. SiC and Cu₁₅Si₄ phases were identified in the as-prepared composites. The interfacial bond between SiC and Cu-Si alloy was tightly and no severe interfacial reaction was observed. The thermal conductivity and coefficient of thermal expansion of the as-prepared 3D-SiC/Cu-Si composite were changed from 89.8 to 55 W·m^-1·K^-1 and 7.512 to 9.64×10^-6 °C^-1 with the temperature increased from room temperature to 500 °C, respectively.

Abstract: SiC/Cu composites exhibit low density, low coefficient of thermal expansion and excellent mechanical properties. In this study, Zn of 2 wt. % was added as the sintering activator, and the high volume faction (60%) SiC/Cu composites was fabricated by hot pressing sintering technology. The phase composition and morphology of as-prepare samples were characterized by X-ray diffraction (XRD) system and scanning electron microscopy (SEM) equipped with an energy-dispersive spectroscopy (EDS) system. The as-prepared SiC/Cu composites were dense and uniform as well as void free. The results show that SiC/Cu composites can reach excellent mechanical properties of SiC/Cu composites. With the increase of sintering temperature, Vickers hardness and the bending strength of the samples increased obviously and the as-prepared SiC/Cu composites achieved a maximum Vickers hardness and bending strength respectively of 195MPa and 140MPa.

Abstract: The cemented carbide tool and high speed steel tool are used as experimental cutting tools. The cutting properties of composite were studied by cutting lathe, tool microscope and light-section method microscope. The results show that carbide and high speed steel tool flank wear rate increase with the increasing of SiC particles size as well as the content of SiC particles. When the particles size of SiC is 40μm, composite cutting surface roughness increases with increasing of the content of SiC particles. While the particles size of SiC is 20μm, composite cutting surface roughness decreases with increasing of the content of SiC particles. In the same cutting conditions, the Carbide tolls have longer life than high-speed steel tools.

Abstract: SiC/Cu composite materials were fabricated by powder metallurgy, and microstructure of composite was analyzed by means of metallographic microscope. The high speed steel tool and cemented carbide tool are used as cutters, and machining performance of SiC/Cu Composites were studied by cutting lathe and wire-electro discharge machine. The relationship between wire-electro discharge machining cutting speed and pulse interval were studied by wire-electro discharge machine. The results show that the composite cutting surface roughness increases with increasing of the content of SiC particles when the size of SiC is 40μm, while composite cutting surface roughness decreases with increasing of the content of SiC particles when the size of SiC is 20μm, the cemented carbide tolls have longer life than high-speed steel tools. The surface roughness of composite increases with the increasing of source voltage, but it decreases with increasing of pulse interval in the wire-electro discharge machining cutting conditions.

Abstract: Copper and 2024 aluminum alloy were melt-infiltrated into porous β-SiC to form SiC/Cu and SiC/Al composites. The porous β-SiC was prepared using Moso bamboo as the bio-template and had structural characteristics of bamboo. The Cu infiltration occurred as low as 1100°C and became significant at 1200°C. After infiltration at 1300°C for 4 h, there was still ~5 % of residual porosity. For the composites with low degree of metal infiltration, the samples fractured like the bamboo-structured porous SiC. For the composites with high degree of infiltration, the sample behaved like monolithic copper. In the infiltration of Al alloy, infiltration occurred at 900°C. Higher Infiltration temperatures would result in significant formation of Al4C3, which gradually decomposed in air.