Fabrication and Corrosion Studies through Weight Loss Method of Aluminium 7075 Alloy Reinforced with Silicon Carbide Particulate in IN NaOH Solution

摘要

In this study 7075 matrix alloy is selected and Silicon carbide particles having average particle size ranging from 50-80um was incorporated into the alloy through liquid melt metallurgy technique using Vortex method. Three different additions of Silicon carbide particulate were made and the weight fractions used are 2, 4, 6%,. The mold is specially designed to produce specimens, the casting are cut in to the cylindrical discs of 20mm diameter and 20mm thickness. The corrosion tests were conducted at room temperature (24°C) using conventional weight loss method according to ASTM G69-80. The corrodents used for the tests were IN Sodium Hydroxide solution. The specimens were washed with distilled water followed by acetone and allowed to dry thoroughly and weighed accurately to fourth decimal place. Weighed specimens were dipped in NaOH solution. Specimens were taken out at every 24 hours interval up to 96 hours. The Corroded specimens were cleaned with brush to remove adhering corrosion product, washed with water and acetone, Then dried and weighed. The corrosion rates were calculated using the formula 534DAT/W. In each case the corrosion rate in Sodium Hydroxide solution decreases and the corrosion becomes ceases. With increase in exposure time for matrix and metal matrix composites due to the aluminium it may induce passivation due to the development of metal hydroxide layer.