Investigation of the Ku band electromagnetic properties of red mud sintered by different methods

The main objective of this study is to reveal the potential of using red mud, a significant metallurgical waste, as an electromagnetic wave absorber material. In this study, initially, red mud obtained from the aluminium sector was analysed physically, chemically, mineralogically, and thermally. Subsequently, samples produced using three different methods (dry-sintered, slip casting-sintered, and mechanically pressed-sintered) were characterized in the Ku band range using a Vector Network Analyzer (VNA) and waveguide measurement kit (WR62) and the EM properties including permittivity and permeability were compared. Permittivity, permeability and loss tangents of the materials corresponding to the Ku band of materials were given. The analysis revealed that the main parameters affecting EM properties are particle size and porosity ratio. In this context, the slip casting-sintered red mud sample showed higher tanδε and tanδμ values compared to the other two production methods. In addition, reflection loss (RL) values of materials were obtained and compared. The study concluded that the shaping method affects the EM properties and holds promise for the use of red mud as an electromagnetic wave absorber material.