PRELIMINARY STUDY ON CLADDING PROCESS ON GRAY CAST IRON SUBSTRATE

Hussein, N. I. S, Kamarul S. R., Ayof, M. N

Abstract: Cladding, also called as hardfacing or surfacing, is a deposition process with a purpose of improving the properties of the substrate accomplished either using laser beam or arc as the heat source for the process. Filler material used in the process is deposited layerby-layer until covering required thickness before being machined to achieve the final dimension. Gas metal arc welding is seen as the best method for accomplishing the cladding operation as the alternative for laser cladding in term of operation cost. The process parameters of gas metal arc welding are discussed on in the aspect of the cladding process. Grey cast iron with its inherent brittleness characteristic is difficult to be weld cladded because the thermal cycle of the cladding process can cause the material to crack. It is understood that the coarse graphite flake structure that gives the lack of ductility characteristic to the material and cause the material to crack when suffer the stress occur during the temperature drop of the process. Nickel based filler material is seen as the best choice to be used for the deposition process because of its ability to precipitate carbon in its free form of graphite and prevent the migration of carbon from cast iron substrate thus avoiding the formation of hard carbide phase. The addition of tungsten carbide in the matrix of nickel base alloy gives the filler material good hardness and wear resistant properties. This paper serves as the preliminary study to get an insight into the understanding of cladding process on cast iron as the substrate before performing the experiment of the cladding operation.

Keywords: Cladding, Hardfacing, Cast Iron, Nickel Based Alloy

DOI: https://doi.org/10.15623/ijret.2013.0211002