| dc.description.abstract | The synthesis of Barium Hexaferrite (BaFe12O19) and Nickel Oxide (NiO) composites using the Mechanical Alloying method as microwave absorbers has been successfully carried out. The wet mixing process of BaFe12O19/NiO was conducted using High Energy Milling at a speed of 450 rpm for 1 hour with ethanol as the medium for the Barium Hexaferrite (BaFe12O19) and Nickel Oxide (NiO) powders, with variations in NiO composition (%wt) of 10%, 15%, and 20%. Each sample was then dried using an oven at a temperature of 100°C for 4 hours. Subsequent heat treatment with a calcination step was performed on each sample at 1000°C for 2 hours. After the calcination process was completed, the samples were ground and sieved using a 100- mesh sieve. Characterization of the samples was carried out using X-Ray Diffraction (XRD) to determine the formed phases, highest peaks, and crystal structure. Scanning Electron Microscope and Energy Dispersive X-ray (SEM-EDX) were used to analyze the structure and morphology formed in each sample, and the Vibrating Network Analyzer (VNA) was used to evaluate the microwave absorption performance of BaFe12O19/NiO with NiO composition variations of 10%, 15%, and 20%. The XRD results identified two crystal phases: hexagonal magnetoplumbite and cubic crystal with a Miller index of 202. SEM-EDX revealed inhomogeneity in BaFe12O19/NiO at 15% and 20% variations. VNA analysis showed that the microwave absorption performance of BaFe12O19/NiO increased with higher NiO composition in the composite. The BaFe12O19/NiO composite with 20% NiO achieved a maximum Reflection Loss value of-11.739 dB at a frequency of 8.18 GHz. | en_US |
