International Conference on Advanced Materials Science Engineeringand High Tech Devices Applications Exhibition (ICMATSE 2020), Ankara, Turkey, 2 - 04 October 2020, pp.44-49
In this study, B4C (5 and 10wt.%) particle-reinforced Al-15Si-2.5Cu-0.5Mg (Ecka Alumix 231®) aluminum matrix composites were produced through cold press/ sintering technique. Sintering process was carried out at three different temperatures (555 °C, 580 °C, 605 °C). The obtained samples were subjected to density measurement, also microstructure analysis and hardness test were examined. Densities of the samples were measured by Archimedes technique according to ASTM B962-08. Optical microscope and scanning electron microscope (SEM) were used in microstructure studies. Macrohardness measurements were performed in terms of Brinell hardness by use of 31.5 kgf load and 2.5 mm ball diameter. The green density of the samples decreased with increasing B4C wt.%. It was determined that the density decreases in all samples with increasing sintering temperature. It was observed that the porosity increases and the pores become larger with increasing sintering temperature. Al-rich solid solution, primary Si and Cu and Mg-rich phases in the microstructure were determined through SEM and EDS analysis. While the hardness increased in 5wt.% particle reinforced composites, it was observed that the hardness decreased in 10wt.% reinforced composites. Samples produced from Alumix 231 powder was give the highest hardness value at 555 °C.