Corrosion behaviour of an SASS 904L plate and its analog (AWS A5.9 ER385) deposited by the arc welding process

The corrosion performance of a metallic material is a characteristic required in several sectors. It is increasingly important due to the growing responsibility and optimization of projects, which require combining low cost and long life, as well as the increasing presence of more corrosive fluids and liquid media that can corrode materials through localized or generalized corrosion. Many tests aim to simulate real-world environments to validate the safe use of the material. The objective of this investigation is to compare the corrosive performance of the SASS 904L plate with the coating deposited with AWS A5.9 ER385 wire by the MIG/MAG-VP welding process (chemically analogous). For this purpose, immersion tests were conducted in ferric chloride and various liquids, including alcohol, gasoline, diesel, and synthetic seawater. Salt spray tests, immersion in SRB, U-Bend tests, and potentiostatic tests were also performed. In almost all tests, the laminated plate demonstrated better performance than the coating, although the difference was not significant. In the tests with ferric chloride, none of the materials met the minimum requirements for the test. These requirements were met for immersion in alcohol, diesel, gasoline, and simulated seawater, as well as in the medium containing SRB. Through the study, it was determined that the materials presented similar behavior, demonstrating that the difference in performance is most likely due to the manufacturing process used, since the materials compared are chemically analogous. The study enables the use of the coating with the proposed pair of materials, thereby opening up opportunities for applications in corrosive environments.