Abstract:
Several coated and uncoated metallic materials were exposed at ten different corrosion sites located in São Paulo state, Brazil, for three years. The exposed metallic materials were: carbon steel, weathering steel, stainless steel, zinc, copper, bare aluminum and anodized aluminum. Additionally, the following coatings applied on steel panels were tested: hot dip zinc, electrolytic zinc, electrolytic cadmium, epoxy-sealed thermal sprayed zinc; thermal sprayed aluminum and epoxy-sealed thermal sprayed aluminum. According to the obtained corrosion rate results, the above mentioned metallic materials were classified as follows: carbon steel, weathering steel, copper, zinc, aluminum and stainless steel. Among the coated materials, the sealed thermal sprayed zinc and aluminum coatings presented only chalking and the anodized aluminum practically did not suffer corrosion. The electrolytic zinc and cadmium presented different behaviour in different atmospheres. The unsealed thermal sprayed aluminum presented only a slight staining in the beginning of exposition which remained unchanged afterwards.
Reference:
KAJIMOTO, Z.P.; SIQUEIRA, F.J.S.; ALMEIDA, N.L. Estudo do comportamento de materiais metálicos expostos nas atmosferas do Estado de São Paulo: parte 1. Tratamento de Superfície, São Paulo, v.9, n.43, p.25-37, fev./.mar., 1990. /e também/ In: SEMINÁRIO DE MATERIAIS NO SETOR ELÉTRICO, 2., 1990, Curitiba. Anais… Curitiba: COPEL, 1990. p. 184-193. (IPT Pub. 1849)
Several coated and uncoated metallic materials were exposed at ten different corrosion sites located in São Paulo state, Brazil, for three years. The exposed metallic materials were: carbon steel, weathering steel, stainless steel, zinc, copper, bare aluminum and anodized aluminum. Additionally, the following coatings applied on steel panels were tested: hot dip zinc, electrolytic zinc, electrolytic cadmium, epoxy-sealed thermal sprayed zinc; thermal sprayed aluminum and epoxy-sealed thermal sprayed aluminum. According to the obtained corrosion rate results, the above mentioned metallic materials were classified as follows: carbon steel, weathering steel, copper, zinc, aluminum and stainless steel. Among the coated materials, the sealed thermal sprayed zinc and aluminum coatings presented only chalking and the anodized aluminum practically did not suffer corrosion. The electrolytic zinc and cadmium presented different behaviour in different atmospheres. The unsealed thermal sprayed aluminum presented only a slight staining in the beginning of exposition which remained unchanged afterwards.
Reference:
KAJIMOTO, Z.P.; SIQUEIRA, F.J.S.; ALMEIDA, N.L. Estudo do comportamento de materiais metálicos expostos nas atmosferas do Estado de São Paulo: parte 1. Tratamento de Superfície, São Paulo, v.9, n.43, p.25-37, fev./.mar., 1990. /e também/ In: SEMINÁRIO DE MATERIAIS NO SETOR ELÉTRICO, 2., 1990, Curitiba. Anais… Curitiba: COPEL, 1990. p. 184-193. (IPT Pub. 1849)
