Tribological Study of Al 6063 Alloy and EN31 Steel Using Biodegradable Oils in Fully Flooded Lubricating Condition

Abstract

Using mineral oil in the cold rolling of aluminum alloy harms the environment. Researchers are developing biodegradable lubricants to take the place of mineral oils. A tribological analysis for the interface between EN31 steel and aluminum 6063 alloy under full flooded lubrication has been done on the pin-on-disc tribometer. In this study, neem and coconut oil have been used as biodegradable oils in fully lubricating conditions between the interfaces of surfaces. Taguchi’s optimization method has been applied to optimize process parameters, such as load, lubricants, and sliding speed. Four type of lubricants LT (dry, coconut oil, neem oil, and rolling lubricant,) were tested, along with sliding speeds s (1.25, 1.5, 1.75, and 2.0 m/s) and loads W (4, 6, 8, and 10 kg). L16 orthogonal array by Taguchi’s optimization technique has been used for the design of experiment. An analysis has been conducted on the tribological properties between the interface of Al 6063 and EN 31 steel. The findings demonstrated that biodegradable oils, such as coconut and neem oil, had good tribological properties. According to S/N analysis, the optimal parameters for the coefficient of friction (COF) were observed as, lubricant at first level, sliding speed at third level, and load at first level (LT1-s3-W1) considering the smaller-the-better condition. For specific wear rate (SWR) optimal parameters were lubricant at first level, sliding speed at third level, and load at fourth level (LT1-s3-W4) considering the smaller-the-better condition. S/N analysis revealed that lubrication type had the most effective in minimizing COF and SWR. Regression models were developed for COF and SWR using ANNOVA. This model had a good agreement with results of experiments.