PRODUCTION OF FG-Al-MMC BY SEMI-SOLID STIRRING AND SEQUENTIAL SQUEEZE CASTING METHODS

Abstract

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.