Estudo e análise da taxa de corrosão de um aço ASTM a 516 grau 60 e das soldas de revestimentos com eletrodo arame tubular AWS E71T e Ledurit 60, em licor branco utilizado na produção de celulose

Abstract

The metallurgical and mechanical industry use large amounts and types of metallic materials subjected to various means, becoming necessary to carry out several standardized tests, aiming to prevent accidents, the corrosion of materials and production stoppage. From its conception to final use in the manufacture of components, steel undergoes thermal and mechanical processes that alter its microstructure changing the steel's performance, reliability and future security. Relating these two common situations in the mechanical area, the paper suggests steel study ASTM A 516 grade 60, used in the construction of digesters in paper mills and pulp, the tubular electrode AWS E71T used in the recovery of walls (thickness) of the digester vessel and a new material option (LEDURIT 60) for this recovery. This study used as electrolyte the "White Liquor", which is used in the production of pulp and paper. This yields the material's corrosion rates as a function of the electrolyte's temperature variation. The results indicate that the 60 LEDURIT material showed better results on corrosion rates. Based on trials, the project took place in the laboratories of the Federal Technological University of Paraná, in Ponta Grossa, and Ponta Grossa State University, Uvaranas campus, fostered by concern over the risk and highly dangerous accidents corrosion can cause.