— The Zinc–Aluminium (ZA) family of casting alloys are gaining wide commercial importance as journal bearing material for high load and low speed applications. These alloys, most notably ZA-27 is capable of replacing traditional bronze bearing at low cost. Recently, the ZA-27 alloy has been substituted for conventional journal bearing materials in a wide range of industrial applications. The journal bearings produced from these alloys have been used in earthmoving equipments, mining and milling machines, cable winches and compressors. The ZA-27 alloys and the bearings were also used in heavy and dusty environments such as underground machines, ore crashers and rock drills.The tribological properties of the ZA 27 alloy were tested using a Pin-on-Disc friction and wear tribotester.Sliding wear tests were performed using the tribotester by varying load, speed & sliding distance. The same tests are done with lubricating condition and also with bio lubricants. The Bio-lubrication is adopted in this work because of its biodegradability and eco-friendly nature. Especially the soya bean oil possess good lubrication properties. The wear rate of dry, base oil and bio lubricant oil condition were determined different applied load, speed and sliding distance compared with each other.

In the field of tribology, Zinc Aluminium (ZA) alloys have been widely investigated for their superior wear characteristics. They were found to be suitable alternatives for bearing bronzes for the operating conditions of high mechanical load and moderate sliding speeds. Addition of nano-particles in the lubricating oil (base oil) to enhance the characteristics of the base oil is known as nano lubrication. In this study, sliding wear behaviour of ZA27 was investigated under dry, base oil and nano oil lubrication conditions, by varying load, sliding distance and sliding speed. With the base oil as SAE 40, nano graphite was added in two step method which was further used to identify the lubrication regime under different lubrication conditions. From the limited study of single melt samples, the results appear that the wear behaviour of ZA27 alloy improved under nano lubrication conditions with reduction in operating temperature. It could be observed from SEM images that the presence of nano-particles reduced scarring and wear, leading to enhancement in the tribological performance of ZA27 alloy.