Corrosion behavior of nickel plated medium carbon steel in cocoa liquor

Abstract

This research work investigated the corrosion resistance of nickel plated medium carbon steel in cocoa liquor. It simulated the effect of continuous use of the material in a cocoa liquor environment where corrosion products are left in place. Medium carbon steel samples were nickel electroplated at 4V for 20, 25, 30, and 35 mins. using Watts solution. The plated samples were then subjected to a cocoa liquor environment for 30 days. The electrode potentials mV (SCE) were measured every day. Weight loss was determined at intervals of 5 days for the duration of the exposure period. The result showed maximum corrosion rate on the nickel-plated steels to be 0.05mm/yr throughout the 30 days. duration of the test while corrosion rate in the un-plated steel was observed to be 0.36mm/yr at the end of 30 days. Generally, it was observed that the thicker the nickel coating, the lower the corrosion rate. The pH of the cocoa liquor was acidic throughout the thirty days test duration. Nickel plating is suitable as a protective coating for mediumcarbon steels in cocoa liquor environment.