Application of Fly-ash Composite in Plasma Surface Engineering

Abstract

Fly-ash produced from iron & steel industries contains rich amount of metal oxides which gives a tremendous potential as a coating material on structural components. This demand leads to develop and characterize different type of fly ash composite coatings by using plasma spray technique. Plasma spray technology has the advantage of being able to process various low-grade ore minerals to obtain value-added products and also to deposit metals, ceramics and a combination of these, generating approximately homogeneous coatings with the desired microstructure. In the present investigation, coatings are developed on copper substrates using fly-ash+ quartz+illmenite composite (in a weight percentage ratio of 60:20:20) at various plasma torch input power levels ranging from 11 to 21 kW DC. Metallographic and chemical characterization of the produced composite coatings was performed with the aid of Scanning Electron Microscopy (SEM) and XRD Analysis. The adhesion strength was measured by using coating pull-out method. Maximum adhesion strength is 6.32MPa found in copper substrate. It was found that the quality and properties of the composite coating are significantly affected by the operating power level of the plasma spray torch. This work identifies fly-ash composite coating as a potential coating material for structural and engineering application.