Production and characterization of Al-Ni/GO and Al-Ni/TiO2 metal matrix composite materials

In this thesis, metal matrix Al10Ni/TiO2 and Al10Ni/GO composites were produced as powder by mechanical alloying method at different reinforcement ratios and different grinding times. Pressed powders were subjected to sintering process at different temperatures. The effects of grinding time and sintering temperature on the structural and thermal properties of the composites were investigated. In addition, the wear behavior of some produced composites under a certain load was investigated. The structural properties of the produced composites were examined by X-ray diffraction (XRD), and the thermal properties were investigated by differential thermal analysis (DTA). After the pressing, sintering, polishing and etching of the composites produced as powder, the surface analysis was examined with an optical microscope (OM) and the surface microhardness was also measured. After calculating the experimental and theoretical densities of the composites, the wear behavior of some composites under 5, 10 and 15N loads were investigated. According to the XRD and OM results, as the grinding time increased, a more homogeneous structure and particle size reduction occurred. The DTA results showed a series of endothermic and exothermic peaks indicating phase transformation and crystallizations during continuous heating. It was observed that as the sintering temperature increased, the formation of new intermetallic phases and microhardness increased. The maximum microhardness value of the produced composites was found as 541 ± 10 HV in the Al10Ni/TiO2 composite sample produced with 20h grinding and sintered at 500 oC. According to these results, it was understood that the mechanical properties of Al10Ni/TiO2 composites were superior to the mechanical properties of Al10Ni/GO composites. Also the analysis results obtained were found to be in agreement with each other and literature.