Corrosion Resistance to Various Environments

Magnesium is susceptible to numerous environmental conditions. Only mild atmospheres and stagnant fresh water which do not break down the MgO surface layer on magnesium are acceptable for magnesium. Any agitation of the water environment or addition of salts into the environment will attack the protective coating and lead to corrosion of the magnesium. Humidity levels of 30% can produce mild corrosion with severe corrosion occurring at a level of 80%. All acids with the exception of hydrofluoric acid and H2CrO4 readily attack magnesium. Magnesium does resist corrosion in the presence of dilute alkalis. Organic acids, such as fruit juices and carbonated drinks severely attack magnesium. Other organic compounds do not affect magnesium at room temperatures but may lead to corrosion at elevated temperatures.