Atmospheric exposure testing of barium metaborate based paints

Barium metaborate as a new less toxic anti‐corrosive pigment was tested for protection against corrosion in an atmospheric exposure testing station set in Egypt on Alexandria seashore. Seventy paints were prepared, based on six grades of laboratory prepared barium metaborate pigments. The paints could be classified into three groups according to the type of the binder; each group comprises seven subgroups according to the pigment grade used. The paints were tested first in the laboratory and then in actual environment. Commercial barium metaborate (Busan 11‐M1) based paints were prepared and used as a blank. High corrosion protection properties are obtained for up to nine years exposure. Results showed that mixing barium metaborate pigments with neutral binder gave better results than mixing them with acidic binder. Laboratory prepared pigments gave better results than the commercial one. It was also found that corrosion protection of these pigments increases with the increase of pigment modification.