Effect of thermal spray coatings on wear behavior of high tensile steel applicable for tiller blades

A rotary tiller is a mechanized agricultural implement popularly used to save time, human effort and fuel in preparation of soil bed. The tiller blades are subjected to extreme surface wear under complex abrasive environments. The aim of this study was to improve the service life of the tiller blade by means of three different thermal spray coatings. Stellite-21, WC-Co-Cr and Cr3C2-NiCr coating powders were deposited on high tensile steel which is being used for tiller blades by pulsed detonation spray technique and wear behavior of these coatings were evaluated by pin-on-disc mechanism at ambient temperature under dry conditions in accordance with ASTM G-99 standard. It was observed that WC-Co-Cr coating on high tensile steel has provided higher wear resistance in abrasion in comparison to Cr3C2-NiCrand Stellite-21. Scanning electron microscopy/energy-dispersive X-ray analysis (SEM/EDAX) and X-ray diffraction (XRD) techniques were used to analyze the worn out surfaces.