In this study an experimental investigation of effects of cutting parameters on surface roughness during end milling of aluminium 6061 under dry condition and minimum quantity lubrication (MQL) condition were carried out. Spindle speed (N), feed rate (f), axial depth of cut (a) and radial depth of cut (r) were cutting parameters chosen as input variables in the investigation of the surface roughness quality. The experimental design adopted for this study was the central composite design (CCD) of response surface methodology. Thirty samples were run in a CNC milling machine for each condition and the surface roughness measured using Mitutoyo surface tester. A comparison showing the effects of cutting parameters on the surface roughness for dry and MQL conditions in end-milling of aluminium were evaluated. Surface roughness values for MQL condition were lower with up to 20% reduction when compared to dry conditions. MQL cutting condition was found to be better and more reliable because it is environmentally friendly and gives better surface finish. With the obtained optimum input parameters for surface roughness, production operations will be enhanced.

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Nano-lubricant machining of Aluminum 8112 alloy is the art of sustainable manufacturing of mechanical components used for defense technology and aerospace application. However, machining aluminum alloys generates excess heat, which tends to increase the cutting force (F.C.), due to the material adhesion of the workpiece on the cutting tool. The challenge has drawn researchers’ attention to introducing nano-lubrication processes. This study focused on the comparative assessment of eco-friendly vegetable oil-based-TiO2 and MWCNTs nano-lubricant on cutting force during the machining of the Aluminum 8112 alloy. Nanoparticles were implemented on the base oil using an ultrasonic vibrator and magnetic stirrer before the application in the machining, via the minimum quantity lubrication process. Quadratic central composite designs were employed to carry out the experiment, using five factors at five levels, having experimental runs of 50. The input parameters are helix angle (H.A.), spindle speed (S.S.), axial depth of cut (ADOC), feed rate (F.R.), and length of cut (LOC). The results show that the application of the nanoparticle increases the performance of the vegetable oil on the cutting force. TiO2 nano-lubricant reduces the cutting force by 0.26%, compared with the MWCNTs, and 6% compared with the vegetable oil. Furthermore, the MWCNT nano-lubricant reduces the cutting force by 5% compared with the vegetable oil lubrication environment.

Surface energetics effects on the mechanical strength of fibre reinforced polymer matrix been studied employed the manual scraper mechanism in extracting fibre from plantain pseudo-stem and was treated with nine different treatments. Cylindrical shape mould was prepared for mechanical test samples with continuous and unidirectional aligned fibres. Two probe liquids; water and glycerol were used in contact angle measurement for all the treated and untreated samples. The contact angle data was used for the interfacial energetics computations using Neumann and Fowkes models and the mathematical analysis were carried out using Matlab software tools. van der Waals notion of particle-particle interaction was employed to explain the physiochemical properties such as the surface interfacial energies. The average value for the interfacial free energy of adhesion for fibre-water and fibre-glycerol are -10mJ/m2 and -16MJ/m2 respectively signifying attractive van der Waal forces. The tensile test results unveil that the average value for treated fibres is greater than the average value of 171.29N/mm2 for untreated fibre except for potassium permanganate and phosphoric acid. These results reveal that an increase in tensile strength leads to an increase in the interfacial surface energy of adhesion. The treated fibres show a significant increase in interfacial surface energy and change in free energy of adhesion which suggests a better bonding mechanism of interaction between the fibre and matrix except for phosphoric acid which reveals otherwise, it may be as a result of the chemical chopped off the fibre during the treatment. The average strain rate of about 0.003 per seconds, 0.002 per seconds and 0.005 per seconds were deduced from the treated Mercerization, Acetone and MEKP respectively which reveals the lower strain rate as compared to the untreated fibre of 0.008 per seconds. The negative strain rate for the potassium permanganate and phosphoric acid was found to be -0.002 and -0.001 respectively reveals that the treatments will debond faster than other treated fibres..