Protection of iron and steel in large outdoor industrial heritage objects

Abstract

Preservation of large outdoor cultural objects containing iron and steel for future generations involves protecting them with a coating. To meet the ethics of the conservation profession and the typical budget, coatings should maintain the original appearance and significance of objects as well as require no maintenance for at least three years. Eighteen coatings, waxes and oils, which met the project's requirements based on peer reviewed research publications, were compared on an equal basis in practice for their potential to inhibit corrosion of large industrial objects. They were applied to test Q panels at equal dry film thicknesses and evaluated by mechanical, atmospheric and accelerated corrosion tests. Uncoated Q panels corroded significantly more rapidly than all coatings, suggesting that any treatment is better than nothing. Interim results suggest that the coatings which clearly inhibit corrosion, as shown by salt spray tests after 504 h, atmospheric corrosion for six months and oxygen consumption were Cosmoloid H80, Dinitrol Car/4941, LPS3, Rustilo 3000, SP400 and VpCI-386.