Protection of ferrous surfaces using zinc based alloys - also contg. magnesium chromium and aluminium

摘要

Ferrous surfaces are given exceptionally stron protection by application of a Zn based alloy coating. The alloy also contains 1-5 (pref. 1-3)% Mg, is not 2% Al, such that the ratio of percentages of Mg:Al is 5 (pref. 1.5-5 esp 1.5-3) and an amt. of Cr so that the ratio of the percentages of Cr: Mg = 0-0.2 and provides the surfaces with unusually high corrosion protection. It is partic. suitable for treating both inner and outer surfaces of steel tubes, as well as steel plates.