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Machining of materials has received significant consideration due to the increasing use of machining processes in various industrial applications. In machining, the heat generated in the cutting zone during machining is critical in deciding the work piece quality. Lubricants are widely used to reduce the heat generation. Their usage poses threat to environment and health hazards. Hence, there is a need to identify eco-friendly and user-friendly alternatives to conventional cutting fluids. Modern tribology has facilitated the use of solid lubricants such as graphite, calcium fluoride, molybdenum disulphide, and boric acid as an alternative to cutting fluids in machining. Solid lubricant assisted machining is an environmental friendly clean technology for improving the surface quality of the machined work piece.

Electroless Nickel (EN) coatings are used in automotive application due to its high hardness, uniform thickness and wear resistance. The study deals with the improvement of surface properties of mild steel by the deposition of Ni-P alloy. The steel specimens were EN coated for various time duration ranging from 0.5 to 3 h. The effect of coating time on thickness, structure, hardness and wear of EN coated steel are investigated. It has been found that the coating thickness is uniform and it increases as the coating time increases. There is no significant change in hardness and wear with increase in coating time. The structure of EN coated steel comprises a surface layer of Ni-P alloy deposit which is instrumental in increase in the hardness. Microhardness of EN coated steel is in the range of 500-540 Hv0.025. The wear rate and coefficient of friction of EN coated steel is found to be low compared to the base metal.