Abstract:
Thiswork sets out a development of the equipment and an evaluation of the process of powder fed transferred arc plasmawelding (PTApowder)with an emphasis on its utilization in coatingmetallic surfaces out of a flat position.After analysing the possibility of using the process in refurbishing hydraulic turbines eroded by cavitation, an analysis was made of the performance of the process and of the influence of the type of current (constant direct current and pulsed direct current) on resistance to cavitation of Stellite 6 alloy in accordance with ASTMstandardG-32/92, by the indirectmethod. Fromthe Stellite 6 alloy coatings deposited by the PTAprocess – powder using constant direct current and pulsed direct current, no significant differencewas observed in the
resistance to cavitation.On the other hand, the resistance to cavitation of the Stellite 6 alloy coatings obtained by the PTApowder process showed a performance higher than that of the Cavitec alloy obtainedwith theMIGandwire fed PTAwelding processes.
Keywords: plasma welding; transferred arc; coatings; Stellite 6
Referência:
Díaz, Víctor Vergara, Dutra, Jair Carlos, de Almeida Buschinelli, Augusto José and D'Oliveira, Ana Sofia. Climaco(2009)'Cavitation erosion resistance of deposits processed by plasma transferred arc welding',Welding International,23:3,159 — 165