SYNTHESIS AND CHARACTERIZATION OF Ni-P BASED ELECTROLESS COATING FOR RADAR APPLICATION

Abstract

The process of electroless deposition is one of the most elegant methods available for the production of coatings. The techniques involves the auto catalytic reduction, at the substrate/solution interface, of cations by electrons released from suitable chemical reducing agents and, a significant degree of elemental release from these agents allowing co-deposition with the reduced metal. The success of the methods stems from the control that can be exercised over the relative strength of the reducing agent in the presence of ligand stabilized metal complexes, allowing alloys of differing composition to be produced. The electroless deposition technique also allows coatings to be produced in amorphous or in crystalline non —equilibrium states, each phase exhibiting its own distinct chemical, physical and mechanical properties, whilst heat treatment, subsequent to deposition, can be successfully employed to generate the more traditionally understood equilibrium phases, thereby extending the range of properties available and therefore the number of applications to which the technique can be used. When electroless coating mixed with ferrite, a type of magnetic material, the coating absorbs microwave energy, which makes its detection by a radar difficult. In this work efforts have been made for the preparation of M type hexagonal ferrite powder, and electroless coating carried out by suspending ferrite with coating solution containing reducing agent, Ni source, inhibitors and complexing agent. After coating the plate was tested for the Ku band between frequency range of 12 to 18 GHz. The ferrite powder was examined by XRD analysis.