Improving the Mechanical and Corrosion Behaviour of Friction Surfaced Aluminium Deposition by Forced Convection Nitrogen Shielding Technique

During friction surfacing of dissimilar alloys, different shielding techniques are used to avoid oxidation and corrosion behaviour of developed coatings. The present study explores the effect mechanical and corrosion performance of friction surfaced aluminium deposits over carbon steel by forced convection nitrogen shielding (FCNS) process. Appropriate friction surfacing process parameters are selected for experimental work, and the substrate plate was maintained a constant preheating temperature of 200 °C for obtaining better deposition. During deposition process, three different volume flow rates of nitrogen gas were supplied, namely FCNS-5, FCNS-10, and FCNS-15. The developed coating’s mechanical strength and corrosion behaviour are intensively investigated and compared with the coating developed by without apply of forced convention process (FCNS-0). The microstructural image received from electron backscattered diffraction (EBSD shows that the restoration activities and dynamically recrystallized grain growth are high towards higher volume of nitrogen supplied during FCNS process; as a result, an improved mechanical strength of the coating was achieved. Furthermore, the corrosion behaviour was analysed by electrochemical impedance and potentiodynamic polarization test. The impedance test shows a less corrosion current of the aluminium coating at FCNS-15 process. The potential dynamic polarization test confirms a lesser I_corr and higher E_corr value of aluminium coating in FCNS-15 process which proved a better corrosion resistance deposition compared to other processes.