Development of 7XXX-Al series composite materials using high-speed mechanical alloying

Abstract

This study aims to homogeneously mix Al, Zn, Cu, and Si metal powders with graphene nanoplatet and SİC ceramic powder reinforcements at various times and different Zn ratios using a high-energy ball milling device (Spex-type Retsch MM 400 model mixer). X-ray diffraction analysis (XRD) was used to investigate the effects of different Zn ratios and alloying times on the alloying process. The XRD data were used to calculate the crystal size using the Scherrer and Williamson-Hall equations. The alloyed powders were sintered and turned into billets. Then, images were taken from the polished surfaces using scanning electron microscopy. In addition, Vickers microhardness measurements of these billets were also examined. The Vickers microhardness test results showed a general trend of increased hardness with prolonged alloying times and elevated Zn content. The increase in composite stiffness can be attributed to two main factors. First, the high concentration of hard ceramic particles in the softer aluminum matrix contributes to this increase. Second, the formation of a robust interface between the aluminum matrix and the ceramic particles also increases the stiffness. This interface ensures efficient load transfer and increases the overall stiffness of the composite. The EDX analysis results also support the XRD findings. A high-strength aluminum alloy composite material has been produced and characterized for aircraft fuselage structures.