Avaliação do processo da eletrodeposição na obtenção da liga NiFeW.

Abstract

Over the years, the corrosion is responsible for several accidents with petroleum that have been occurred. To prevent the corrosion effects it's necessary to develop advanced materials with high anti-corrosion properties. The electrodeposition has been one of the most important techniques in obtaining these materials and the operational parameters are well established and available in the literature. The proposal of this work is to develop and optimize the parameters to obtain a new NiFeW alloy with good anticorrosive properties. The optimization of the process was accomplished by a factorial design 2k with 2 center points. The variables influence as well the interactions between them was evaluated. The results showed that the best bath composition was 0.025M nickel sulphate, 0.005M iron sulphate and 0.300M sodium tungstate, using as operational parameters 50mA/cm2 current density and a temperature of 30°C, achieving a current efficiency of about 26% and a corrosion resistance of 1,960x10 £2. The obtained alloys showed brightness, adherence and good corrosion resistance.