polimeros

Encontro e Exposição Brasileira de tratamento de superficie
III INTERFINISH Latino Americano

INVESTIGAÇÃO DA CORROSIVIDADE DO ENSAIO DE NÉVOA
SALINA SEGUNDO NORMA ISO 9227
D. O. Souza1; N. P. Hammel1; W. I. A. Santos2; A. H. Ramirez2; N. Rojo1; I. Costa2
1
Equilam Industria e Comercio Ltda.
2
Instituto de Pesquisas Energéticas de Nucleares – IPEN

ABSTRACT
Chambers used for salt spray tests are designed to allow control of the factors that influence corrosion. The aim of these tests is to replicate the results that occur in real atmospheric conditions. However, the large range of aspects that contribute to atmospheric corrosion does not permit an accurate reproduction of the climatic exposure. Small variations in the chamber calibration can mask the results. Consequently, it is of great importance to ensure the corrosivity validation of the chamber. The aim of this work is to evaluate the aggressiveness of a salt spray chamber according to ISO 9227:2006. Eighteen coupons of 1008 carbon steel (CR4-ISO 3574) were prepared with dimensions of 150 mm x 70 mm x 1 mm. These were positioned in six different regions inside a salt spray chamber. The salt solution was prepared at a concentration of 5% NaCl and pH ranging from 6.5 to 7.2. The test was carried out for 48 hours. After this period, the weight loss of the coupons per square meter was calculated, and the mean and standard deviation were estimated. According to ISO 9227:2006 standard, for test validation, the mean weight loss and standard deviation has to be (70 ± 20) g/m2. The weight loss results obtained ranged from 66.26 to 79.31 g/m2, validating the corrositivy of the chamber used.

RESUMO
Câmaras de névoa salina são projetadas para reproduzir os resultados que ocorrem nas condições reais de intemperismo. Entretanto, o leque enorme de fatores atmosféricos que contribuem com a corrosão não permite uma reprodução precisa da exposição natural. Pequenas variações na calibração do