The Effect of electrolyte concentration and temperature at electroplating with copper on the plate thickness and corrosion rate of plated gray cast iron

Abstract

The purpose of this research is to find the effect of variations in the concentration of electrolyte solution and the temperature of the electroplating copper coating on gray cast iron to produce a thick copper layer and reduce the corrosion rate on the pump Impeller of gray cast iron. The test specimens of gray cast iron were 30 pieces, with dimensions according to the ASTM G31-72 corrosion rate testing standard. Then the specimen was coated with copper electroplating with various solutions of 1 (195 g/l copper sulfate, 45 g/l sulfuric acid), solution 2 (205 g/l copper sulfate, 50 g/l sulfuric acid), solution 3 (215 g/l). l copper sulfate, 55 g/l sulfuric acid), with an immersion temperature of 30 °C -34 °C, 40 °C -44 °C, and 50 °C -54 °C in each solution. After being coated with copper, the coating thickness test is carried out using a digital coating thickness gauge (F&NF type). Then the corrosion rate test was carried out using the weight loss method with the ASTM G31-72 standard, which was immersed in seawater for 240 hours. The test results show the highest average thickness in solution 3 and a coating temperature of 50 °C -54 °C of 27,46 μm, and the lowest average thickness of solution 1 (and a coating temperature of 30 °C -34 °C of 26.23 μm. The lowest corrosion rate is in solution 3, and a coating temperature of 50 °C -54 °C is 0,0041 mmpy, while the value of the highest coating corrosion rate is in solution 1 and a coating temperature of 30 °C -34 °C is 0,007909 mmpy. When compared with specimens without coating the corrosion rate of 2,2947 mmpy.