Mekanik alaşımlama ile üretilen Al4.5Cu/TiO2 kompozitlerinin mikroyapı, sertlik ve termal özellikleri

Abstract

Al4.5Cu/TiO2 composites were fabricated from their elemental powders by the mechanical alloying method. Microstructural and thermal properties of the composites were investigated by a combination of differential thermal analysis (DTA), scanning electron microscopy with energy dispersive X-ray detection (SEM-EDX), and X-ray diffraction (XRD). Microstructural evolutions, phase transformations, and crystallite size changes were investigated depending on the milling time. XRD and SEM results showed that there were a more homogeneous structure and shrinkage in grain size due to the increased milling time. The DTA results showed an endothermic peak of around 650 oC which indicates the melting temperature of Al. Besides, the mechanical properties of the pressed and sintered composites were investigated by Vickers micro-hardness testing. The results showed that microhardness values significantly increased as milling time increased from 5h to 10h. The maximum microhardness value of 173±10 HV was obtained for Al4.5Cu with 20 wt% TiO2 composite after milling for 10h.