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In this study, CNT-A356 composites were obtained by reinforcing an aluminium alloy A356 matrix with 4 different ratios (0.5, 1, 1.5 and 2%) of carbon nanotubes, and hardness, wear and microstructure properties of these composites were investigated. Powder metallurgy method was used for producing composites. A356 powders and CNTs were mixed via ball milling for 1 h, and cold pressed in powder pressing mold. After that, mold was taken into a functional furnace, and hot pressing operation was carried out. Pressed bulk was sintered in a vacuum atmosphere (10 −6 mbar) at 550 • C for 1 h. Hardness measurements, wear tests, and microstructure analyses of produced samples were performed. As a result of experimental studies, CNTs were observed to be located as agglomeration among matrix grains, and a more hollow structure was formed by increasing CNT ratio. Moreover, weight loss increased as hardness values decreased when CNT ratio exceeded 1%. The highest hardness value was measured in composite with 1% CNT.

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This study focused on the formability of aluminium alloy (7075-T6) sheets through hydroforming route. Formability of these sheets was tested using a warm forming setup at three different temperatures and four different die corner radii. Forming limit diagrams (FLD) were generated by measuring the grids of the sheet formed. The results show that the forming limit of AA7075-T6 can be significantly improved when the blank was heated to 140-250 • C. It was also observed that as the temperature increases above 140 • C, dome height began to decrease. Also the results indicated that both the die corner radius and temperature have a significant effect on the stress-strain curve and warm forming of AA7075-T6 sheets. Thus, with the temperature increased from room temperature (RT) to 140 • C, the flow stress decreased and the strain increased, hence, the formability is enhanced. However, further increase in temperature causes decreases the flow stress and strain. Similar changes of the flow curve were seen in die corner radius. Decreasing the die corner radius decreases the flow stress and increase the strain. Moreover, an equation was obtained by establishing correlations between the experimental parameters and their results. In this way, it became possible to make predictions.