Abstract
The present investigation aims to study the improvement of the composite surface hardness by air abrasive jet polishing (AJP) of SiO2 particles. The experiments were conducted by synthesizing Al-TiC composites through melting the aluminum at 850 degrees C and added TiC gradually for 10 minutes to the liquefied aluminum with different sizes and ratios (300-500 nm and 100-200 mu m) and (5, 10, 15, 20 and 25 wt.%) respectively of TiC. The molten Al-TiC was poured to a previously prepared sand mould. The hardness improvement for pure Aluminum, Al- micro-TiC and Al- nano-TiC composites were 7%, 11%, and 15% respectively. The obtained results demonstrate the importance of superficial hardening of composites Al-TiC by impact of the SiO2 air jet and show that the surface hardness improvement is greatest for the nanocomposites compared with microcomposite and pure matrix material.