Tribology of Electroless Ni-P Coating Under Lubricated Condition: An RSM and GA Approach

Friction and wear behavior of electroless Ni-P coating under lubricated condition is studied on a block – on – roller type tribo – tester by varying applied normal load, sliding speed of the roller and sliding time. Electroless Ni-P coating is deposited on AISI 1040 steel substrates. Surface morphology, phase transformation, composition and analysis of wear mechanism are done using scanning electron microscope, X-ray diffraction techniques and energy dispersive X-ray analysis respectively. Based on Taguchi experimental data, a multiple regression model is fitted to relate the coefficient of friction and wear depth with the tribo – testing parameters. Three dimensional surface and contour plots are generated to analyze the trends in variation of the response variables with the interaction of the process parameters (load, speed and time). Significant improvement in wear depth and COF of electroless Ni-P coating is observed under lubrication. Optimization of wear depth and coefficient of friction is conducted using genetic algorithm.