Characterization of Barium M-Hexaferrite with Doping Zn and Mn for Microwaves Absorbent

The research was conducted to examine the content of Fe and other metal in natural sand of beach Ampenan, Mataram, Indonesia which is expected to be used as microwave absorbent material. Characterizations of the electrical and magnetic properties Barium M-Hexaferrite (BaM) with Zn-Mn doping (BaFe12-2xZnxMnxO19) are biosynthesized. Research carried out among others tested the metal content of Fe and other metals, synthesize BaFe12-2xZnxMnxO19. The samples were characterized using Vibrating Sample Magnetometer (VSM) and Network Vector Analyzer (VNA) for the test properties of electricity and magnetism, as well as the absorption of microwaves. The results from the AAS (Atomic Absorption Spectroscopy) testing showed that each gram of magnetic minerals in the natural sand containing 16.27 mg Fe, which states that the majority of metal components content is 69.80% Fe metal with the Magnetite and Hematite phases. The result from VSM showed that the coercivity value decreased when doping ion concentration and calcination temperature increased (0.16 Tesla at 600°C for x = 0.0 and 0.09 Tesla at 800°C for x = 1.0). Value of magnetic saturation and the magnetic remanence decreased with increasing ion concentration (Ms= 4.94 emu/g at x = 0.0 decreased to 0.31 emu/g at x = 1.0) and Mr = 3.43 emu/g for x = 0.0 decreased to 0.06 emu/g at x=1.0. These indicates that the sample has been soft magnetic. The result from VNA showed that the electrical conductivity values measured in the range 8.0-15.0 GHz indicate that the sample is a semiconductor (1.62×10-2 S/cm). The result from VNA showed that the microwave absorption properties increased at higher concentration of doping ions and the calcination temperature would increase the value of Reflection Loss (RL). Maximum RL value of the sample is -14.37 dB at 15 GHz and the absorption coefficient of 96.34%. These results indicate that the BaFe10.8Zn0.6Mn0.6O19 sample can be applied as a microwave absorbent material on X-band to Ku- band frequency. Keyword: Characterization, Barium M-Hexaferrite, doping, microwave, absorbent.