Effects and Characterizations of Pulse Electrodeposition Parameters of Silver on Surface Roughness and Scattering Parameters of Horn Antennas

Abstract

Electronic conductivity is a parameter that exhibits the free-electron transportation ability of a material. The radiation efficiency of reflector type antennas and insertion loss of waveguide transmission lines are directly related to the conductivity of the materials used to construct such structures. Signal quality of antenna and waveguides in the transmission of electromagnetic waves are also very much dependent on the surface finish that has good conductivity [1]. The use of pulse currents produces homogenous deposits of better surface finish than direct current [2,3]. Effects of pulse parameters on the surface properties of silver coatings of the copper base material have been analyzed in terms of surface roughness and S-parameter (scattering parameter). Grain morphologies of silver coatings were characterized by SEM and XRD. The duty cycle, frequency and the average current density were selected as three pulse parameters. Three levels were selected for each parameter in the experimental design. A relationship was developed for surface finish in terms of duty cycle, average current density and pulse frequency. The S11 scattering parameter observations were made relative to a gold-plated reference coupon. It was analyzed that smoother surfaces had more reflection power in terms of S11 parameter thus decreasing the loss of radiation. Therefore, the results may be used to develop a silver coating procedure to improve signal quality of antenna and waveguides in the transmission of electromagnetic waves. [1] Balanis, C. A. (1989), “Advanced Engineering Electromagnetics”, John Wiley & Sons [2] Chandrasekar, M.S. and Pushpavanam, M. (2008) ‘Pulse and pulse reverse plating—Conceptual, advantages and applications’, Electrochimica Acta, 53(8), pp. 3313–3322. [3] Arslan, B., Demirci, G., Karakaya, İ. and Erdoğan, M. (2015) ‘Formation of gold-plated electroformed copper structures’, Advances in Materials and Processing Technologies, 1(3-4), pp. 384–393.