Operational Aspects of Coatings Welds: Erosive Wear and Cavitation

Abstract

The GMAW process using two wires is an alternative to a coating process when high productivity is desired. The potential variants emerging from this process are GMAW cold wire and GMAW double wire. One of the greatest difficulties is the setting of its parameters, which duplication compared to conventional GMAW and also act in a dependent manner. A greater understanding of the technology applied to coatings on turbines in various positions is critical to master the process and its variables for enhancing industrial applications. This study involves an experimental evaluation to verify the influence of some variables on the profile of cord and wear resistance. This paper proposes making deposits with weld metal AWS 308LSi stainless steel and alloys of cobalt (Stellite 6 and 21) plates in carbon steel SAE 1020 in the flat positions. The wear characterization in the lining is used to determine the hardness and surface topography. It is concluded that cobalt alloys have superior resistance to erosive damage, with emphasis on Stellite 21 with respect to erosion and Stellite 6 with respect to cavitation. Mixtures of austenitic stainless steel and cobalt alloys have intermediate wear values. Therefore, it is essential to study welding processes with multiple wires, as proposed in this paper, to determine the optimal combination of alloys for resistance to cavitation-erosion phenomena.