Preparação e análise de desempenho de uma pasta condutora a base de cobre e prata

Abstract

This research presents the preparation of a conductive paste using silicone rubber like a base material with scattered particles of conductive metals, copper and silver. The electrical connections that interconnect bars and electrical components are very important, however, researches show that the effective contact area is only about 1%. Thus, is sought the development of conductive paste that have to submit cost e benefit, which present in viscous form, allows improving the contact area of connections. Consequently, reduction of losses in the form of heat and improvement electrical conductivity between the parties. For this purpose, metal powders of copper and silver were produced and these were mixed with the silicone polymer at different concentrations and in each sample being only one type of metal. After preparation of the paste, it were applied on a connection between copper bars that are arranged in a circuit. Were, then, measured the heating region through a thermal imager and through the obtained temperature, the electrical conductivity and resistivity were calculated. Considering the temperature variation, were determined that the performance of silver containing samples was higher than the performance of the samples containing copper. The best concentration was 90% silver. Considering cost and benefit, the use of the paste containing 50% silver may be more advantageous because the change in temperature is slightly higher than the highest concentration, the cost is about 40% lower and viscosity allow better application.