A new criterion has been developed to predict the onset of liquid (heavier fluid) entrainment from a stratified two-phase region. The criterion was developed based on the local instability of the interface between two fluids due to the suction effect associated with the discharging of the lighter fluid. To validate the proposed criterion, comparisons were conducted between the measured critical height at the onset and those predicted using a three-dimensional analysis of the flow through two configurations: (1) a single branch mounted on an inclined wall with an inclination angle ranging between −90° and + 60° and (2) dual branches mounted on a vertical wall with the plane passing through the branch centerlines and inclined with an angle α ranging between 0° and 60°. Comparisons demonstrate a very good agreement between the predicted and the measured values for both single and dual branches. This verifies that the onset of liquid entrainment mechanism occurs due to local flow instability of the interface, analogous to Rayleigh–Taylor instability.

In this work, carbon steel surface was coated with Al2O3–40 wt% TiO2 composite using thermal spraying method. The tribological properties of the plasma-sprayed Al2O3–40 wt% TiO2 coating were investigated with a tribometer (pin-on-disc) to evaluate and compare the wear properties of coated and uncoated samples under different loads. Additionally, cumulative weight analysis was done to compare wear loss. The results indicate significant anti-wear improvement with an increase in TiO2 from 13 wt% to 40 wt%. The corrosion on coated and uncoated samples was analyzed using AC and DC methods, namely open circuit potential from potentio-dynamic polarization and electrochemical impedance spectroscopy in 3% NaCl solution for 20 days.

End milling is a multipoint cutting process in which material is removed from a workpiece by a rotating tool. It is widely used in cutting 2.5D profiles such as point-to-point, contouring, and pocketing operations. 2.5D machining possesses the capability to translate in all 3 axes but can perform the cutting operation in only 2 of the 3 axes at a time. This study focuses on optimizing the cutting parameters, such as machined surface inclinationangle, axial depth of cut, spindle speed, and feed rate for better surface integrity, namely, microhardness, residual stress, and microstructure in 2.5D cutting utilizing a titanium-coated carbide ball end mill. An optimization method known as Taguchi optimization, which includes planning, conducting, and analyzing results of matrix experiments, was used in order to achieve the best cutting parameter level. Data analysis was conducted using signal-to-noise () and target performance measurement (TPM) response analysis and analysis of variance (Pareto ANOVA). The optimum condition results obtained through analysis show improvements in microhardness of about 0.7%, residual stress in the feed direction of about 18.6%, and residual stress in the cutting direction of about 15.4%.

Binary (Ti/TiN and Cr/CrN) and ternary (TiCr/TiCrN) thin films were deposited on AL7075-T6 by magnetron sputtering. Microhardness, adhesion strength and pin-on-plate wear tests were performed to investigate coating performance. Field emission scanning electron microscope integrated with focused ion beam milling and energy dispersive X-ray spectroscopy was employed for microstructural and chemical characterizations. The tribo-mechanical test results revealed that Cr/CrN promoted up to 5 times greater hardness, Ti/TiN showed the highest scratch resistance and up to 8 times reduced wear, while TiCr/TiCrN favored the least friction and surface roughness. Furthermore, the excellent tribological properties of coatings correlated with their superior adhesion to AL7075-T6.