AA7075 aluminum alloy was reinforced with B4C particles to produce aluminum composite materials. In the production of AA7075/B4C composite materials, the semi-solid mixing method was used for homogenous reinforcement dispersion and low-pressure solidification. For determination of the mechanical properties of the obtained samples, three-point bending, compression and hardness tests were performed. Additionally, the microstructure, reinforcement matrix interface and chemical structure of the produced composite material were investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS) and X-ray diffraction (XRD) analyses. As a result, it was observed that, by using the semi-solid mixing method, the reinforcing powders could be distributed homogeneously into the matrix, both chemical and mechanical bonding could be facilitated between the matrix and the reinforcing material, and this mixing technique could be easily used in production of particle-reinforced metal composites. As the reinforcement rate increased, bending strength increased, but there was a reduction in comparison to the non-reinforced aluminum alloy. As the reinforcement rate increased, compressive strength was observed to decreased, while the mean hardness value increased.

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This study aims to recycle pure magnesium chips by a two-stage mechanical processing method. In the present study, the feasibility of recycling pure magnesium chips with the help of commercially pure magnesium powder was investigated. For this study, the magnesium chips mixed with dierent amount of magnesium powders in the range of 2575 wt%, after mixing by hand and cold press, are subjected to hot extrusion to provide homogeneous microstructure. Furthermore, the eect of magnesium powder and their amounts on the mechanical properties and corrosion behaviour of the recycled magnesium alloys were studied. The results of the mechanical and corrosion test showed that the hardness and compressive yield strength decreased with increasing chip content, while increase in the chip weight fraction in the initial mixture resulted in a signicant increase of corrosion resistance.

In this study, manufacturing of functionally graded ceramic reinforced aluminum matrix composite materials (FG-Al-MMC) by using direct semi-solid stirring and sequential squeeze casting method has been investigated. As a matrix material Al-7075 and as a reinforcement material SiC ceramic particles have been chosen for composite materials of FGM layers. Aluminum composite mixtures with different reinforcement ratios have been prepared by mechanically mixing SiCp reinforcements into semi-solid aluminum alloy and, FG-Al-MMC's have been produced by pouring the composite mixtures into a mold on top of each other in liquid form where each layer has been solidified under pressure. The partial melting of the previous layer due to the added liquid layer and the applied pressure cause bonding between layers with a transition region. This process has been repeated sequentially until a structure with the desired thickness and features were obtained. The structure formed between the layers with this manufacturing method was investigated by taking samples from different layers and transition regions of FG-Al-MMC. Density analyses, spectrometric analyses and optical analyses were carried out to determine the properties of FG-Al-MMC material. As a result, it is observed that successful production of functionally graded aluminum composite materials by the direct semi-solid stirring and sequential squeeze casting methods is possible.