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Molybdenum (Mo) thin films are widely used as a back contact for CIGS-based solar cells. This paper determines the optimal settings for the sputtering parameters for an Mo thin film prepared on soda lime glass substrates, using direct current (dc) magnetron sputtering, with a metal Mo target, in an argon gas environment. A Taguchi method with an L9orthogonal array, the signal-to-noise ratio, and an analysis of variances is used to determine the performance characteristics of the coating operation. The main sputtering parameters, such as working pressure (mTorr), dc power (W), and substrate temperature (°C), are optimized with respect to the structural features, surface morphology, and electrical properties of the Mo films. An adhesive tape test is performed on each film to determine the adhesion strength of the films. The experimental results show that the working pressure has the dominant effect on electrical resistivity and reflectance. The intensity of the main peak (110) for the Mo film increases and the full width at half maximum decreases gradually as the sputtering power is increased. Additionally, the application of an Mo bilayer demonstrates good adherence and low resistivity.

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This paper presents an experimental investigation on the turning of Inconel 718 using tungsten carbide and cermet insert tools with ultrasonic-assisted. The Taguchi method as well as an L18 orthogonal array, signal-to-noise (S/N) ratio and analysis of variance (ANOVA) are employed to examine the performance characteristics of the turning operations. The effect of the machining parameters (cutting tool, depth of cut, cutting speed, feed rate, working temperature and ultrasonic power) on roundness and flank wear in the turning operations are studied. For roundness, depth of cut (σ = 38.40 %) and feed rate (σ = 22.59 %) were recognized to make significant contributions. For flank wear, the significant contribution order was cutting tools (σ = 51.16 %) for different materials, follow working temperature (σ=22.37 %), depth of cut (σ = 13.59 %), and ultrasonic power (σ = 5.79 %). Cutting with ultrasonic-assisted improves roundness by 17.78 % to 45.73 %, and improves flank wear by 26.52 % to 46.26 7%. Finally, turning experiments with 5-20 nm nano-particles cutting fluid were investigated. The experimental results indicated the cutter-workpiece friction force is noticeably reduced and cutter service life is prolonged.