Mechanical and microstructural behaviour of wear resistant coatings on cast iron lathe machine beds and slides

The beds of the lathe and slides are subjected to abrasive and fatigue wear, which significantly affects their working life. The objective of this study is to enhance the useful life of the beds and slides. Detonation gun (D-Gun) sprayed WC-Co-Cr and Al2O3 + 40TiO(2) coatings on cast iron imitating lathe machine beds and slides with bare metal are analysed. The wear tests were performed on pin-on-disc apparatus using ASTM G99 standard for the uncoated and coated samples of cast iron. Coatings have been characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. The results of coating characterization, experimental wear data generated, SEM micrographs along with energy dispersive spectroscopy (EDS) of the worn samples were used to analyse the wear behaviour of coated and uncoated cast irons. The results show that WC-Co-Cr and Al2O3 + 40TiO(2) coatings have been successfully deposited on cast iron by detonation gun spray process. The coated material has shown significantly less wear loss as compared to the uncoated material. The cumulative weight loss for detonation sprayed coatings increases with increase in load. The WC-Co-Cr coating has undergone minimum wear. Thus WC-Co-Cr coating deposited on cast iron has shown minimum wear as compared to Al2O3 + 40TiO(2) coated and uncoated cast iron.