Alternative composite design from recycled aluminum chips for mechanical pin-joint (Knuckle) applications

In this work, an alternative aluminum matrix composite (AMCs) was designed from the recycled chips of the aluminium series of AA7075 (90 wt %) and AA1050 (10 wt %) given by French aeronautic company through combined method of powder metallurgy followed by Sintering + Forging. We aimed for the application for the connection link in a mechanism to transfer motion, for example; between the two railways wagons etc. and also some connecting link in aeronautical pieces as an alternative replacement for conventional alloys used in this area. First of all, A typical Al-Zn-Mg-Si-Ni matrix was developed and reinforced basically with B₂O₃ (5, 10%). Chip milling was performed using high energy milling in a planetary ball mill with an inert argon atmosphere to prevent oxidation of the powders. Two compositions were prepared with two different percentages of B₂O₃ and also one composition was kept without reinforcement for comparison with the reinforced ones. Mechanical properties, compression and dynamic drop weight tests of these composites designed here can be improved with the doping process and doping volume fractions. Micro-hardness results were compared according to the optimization conditions of the doping and the reinforcement. Static compression and impact-drop weight tests were carried out. The microstructure analyses have been carried out by Scanning Electron Microscope (SEM).