Studies on the Corrosion Behavior of Deposits Carried out by Thermal Spraying in Electric ARC – Thermal Activated

Abstract

This paper presents a comparative study on the corrosion behaviour of the Al depositions, obtained by thermal spraying in electric arc - the classic method (ASP) and the Al deposits behaviour, carried out with a thermal spray combined device (CTSD). The use of CTSD allows the thermal field modification of the spraying jet and implicitly the modifying the mechanical, physical and chemical properties of the deposits of aluminium. Evaluation of the corrosion behaviour of the aluminium deposits was achieved by exposure to salt water - sea water (3.5NaCl). The corrosion products, formed on the surface of the coatings, were investigated based on the photographic records, electronic microscopy – SEM and X-ray diffraction. The aluminium oxide, obtained on the depositions, carried out by using CTSD - exposed in saline environment is more adherent then the oxide obtained on the deposits, carried out through ASP - which leads to a loss in thickness.