The effect of heat treatment on the open circuit potential of magnesium sacrificial anode

Abstract

Magnesium sacrificial anode that possess high value of open circuit potential, Eoc is needed as it can protect larger area of underground metal structure in cathodic protection. Solution treatment was applied on magnesium sacrificial anode at 150, 200, 250, 300 and 350 °C for 8 hours and cooled in different medium (furnace, air, water, iced water and iced salt water) to obtain the above criteria. The open circuit potential versus saturated calomel electrode was studied in backfill solution using by Gill/AC Potentiostat. It was found that low solution treatment at 150 °C with high cooling rate gave the highest value of open circuit potential, whereas solution treatment at high temperature (350°C) with iced water quench gave the lowest value of open circuit potential.