Uticaj parametara nanošenja NiCr prevlake plazma sprej postupkom u atmosferskim uslovima na njene mehaničke karakteristike i strukturu

Abstract

Prevlaka koja je ispitivana u ovom istraživanju (NiCr prevlaka) dobijena je nanošenjem praha legure nikla i hroma (u procentualnom odnosu 80/20), korišćenjem plazma sprej postupka u atmosferskim uslovima. Ova prevlaka se pre svega primenjuje kako bi povećala otpornost na oksidaciju i koroziju pri visokim temperaturama osnovnog materijala. Kvalitet ovako dobijene prevlake zavisi od više parametara koje treba pažljivo izabrati kako bi se dobile prevlake sa najboljim karakteristikama, a u zavisnosti od željene primene. Pri izboru parametara nanošenja kao osnovni parametar je uzeto rastojanje plazma pištolja od osnove. U ovom istraživanju su korišćene tri grupe uzoraka NiCr prevlaka, dobijene sa tri različita rastojanja plazma pištolja od osnove. Mehaničke karakteristike i mikrostrukture dobijenih prevlaka su analizirane da bi se došlo do optimalnih parametara nanošenja tj. do onih koji daju najbolje rezultate.

The coating investigated in this research (NiCr coating) was obtained by the deposition of nickel and chrome alloy powder composed of 80% Ni and 20% Cr. Process used for coating deposition was atmospheric plasma spraying (APS). The application of this coating is primary as protection of the base material against oxidation and hot corrosion. The quality of coatings deposited by APS depends on several parameters, and all these parameters should be carefully selected in order to obtain the best coating properties for each application. During the selection of the deposition parameters the distance of the plasma spray gun from the substrate was chosen as the base parameter. In this research, three groups of the NiCr coating specimens were produced with different spray distance parameter. Their mechanical properties and microstructure were analyzed in order to find the optimal spray parameters i.e. the ones that give the best mechanical and structural characteristics of the coating.