TSA Coating Service
Thermal sprayed aluminium (TSA) coatings are widely specified for the protection of steels from aqueous corrosion, including offshore structures and components that are exposed to seawater immersion, tidal and splash zone environments. In this paper, the performance of TSA coatings prepared by conventional and newer wire thermal spray systems is presented. The TSA coatings were characterized in terms of deposition efficiency, coating micro structure including porosity and oxide content, surface roughness and coating adhesion. A cost analysis for coating deposition using the various systems is included.
The corrosion behavior of the coatings was compared using an accelerated electrochemical corrosion test method. In addition, longer-term free immersion tests of up to 31 days were conducted in 3.5wt% NaCl solution, pH 7.9-8.2, 22-25°C. The TSA coating performance was quantified in terms of its free corrosion potential and the corrosion rate which was estimated from linear polarization resistance (LPR) measurements. The ability of the TSA coatings to provide adequate cathodic protection to exposed bare steel in immersed saline environment has been demonstrated. The newer systems have been shown to produce TSA coatings of improved quality and the effect of this on longer-term corrosion protection of steel substrates in immersed saline environment is discussed.
Thermal Spray coating of Aluminium involves deposition of
Aluminium of 99.5% purity over the prepared abrasive blasted
surface. The sprayed metal is melted by using electric arc that is
atomized with compressed air and projected over the
substrate. According to the IS & BS Standards, the coating
should be resistant up to 950 C temperature.
The Aluminizing process is used to protect parts operating in
high temperature environments against corrosion and
oxidation. As a result, the most common parts coated are high
temperature industrial chimney and muffler.
No size limitation
Better surface preparation
Pure aluminium coating
Ideal surface for painting
BS: 2569 Part I & II