The current study focuses on investigating the effect of milling parameters on the microhardness during dry and flood milling of Ti-6Al-4V. Dry and flood milling were performed while varying spindle speed (120, 150, and 180 rev/min), depth of cut (1, 1.5 and 2 mm), as the feed rate (4.6 mm/min) was kept constant. Subsequent to milling, milled surfaces microhardness were measured and microstructure evolution was analysed using an optical microscope. It was established that the deformation of beta phase increased with increase of spindle speed during dry milling while during flood milling there was no microstructural change associated to the increase of the spindle speed. On the other hand, the hardness increased as result of increase of spindle speed during both dry and flood milling. Flood milling generated a maximum hardness of 338.44 HV at 180 rev/min which is superior to maximum hardness of 336.36 HV produced during dry milling. Dry milling at 1.5 mm depth of cut generated maximum deformation of beta phase while during flood milling maximum deformation was recorded at 2 mm depth of cut. The hardness increased with increment of depth of cut during flood milling while it decreased with increase of depth of cut during dry milling.

To fabricate joints of dissimilar materials such as alumnium and titanium with excellent joint properties with limited defects, there is a need to use effective joining techniques. Friction stir welding (FSW) and friction stir spot welding (FSSW) are solid-state welding techniques considered environmentally friendly joining techniques. The two techniques have been used to join numerous materials including aluminium, copper, and titanium. Joining dissimilar materials has seen a signifcant expansion worldwide due to the high demand for dissimilar joining exhibiting specific properties to be used for specific applications. This short review presents the resulting properties of joints made with aluminium and titanium using friction stir welding and friction stir spot welding. Microstructure evolution, mechanical properties, and other properties are presented and critically reviewed. Many aluminium and titanium alloys have been welded using several process parameters and tool geometries. In FSW, it has been seen that aluminium/titanium exhibited high strength when the rotational speed is well controlled. From the gathered information, it was concluded that the tool rotational speed was associated with heat input and low speed resulting in low heat input. This produced fine recrystallized grains, especially at the joint interface. On the other hand, FSSW has also been utilized to weld Al to Ti. The results showed that parameters such as rotational speed and dwell time had an impact on the formation of intermetallic compounds (IMCs) including Ti₃Al and mechanical properties were achieved. It was observed that FSSW between aluminium and titanium has not been well researched; therefore, there is a need to further study the behavior of the two materials when spot welded. It is expected that the augmentation of knowledge on the fabricated joint behavior will lead to the expansion of these techniques for specific applications and to the optimization of FSW and FSSW between alumnium and titanium alloys.

Climate change and water pollution are the global focus to address the mitigation measures that will improve water quality and wastewater management. The recent increase in dye pollution from the manufacturing sector, particularly the textile industries, has increased the demand for advanced wastewater treatment technologies that are sustainable and affordable. The abundant, renewable lignocellulosic fiber-based adsorbents have emerged as a promising alternative for removing a wide range of heavy metals and dyes. This review highlights in detail various sources of fibers, their physicochemical compositions, and different modification techniques that improve their selectivity and adsorption capacity, particularly for dye removal. The complementary impacts of the presence of the inherent functional groups, specific surface charges, and the primary adsorption mechanisms that can significantly enhance dye selectivity have been well addressed. While the modified fibers demonstrated the promising removal efficiency of above 90% at the laboratory scale, challenges remain in terms of their adsorption kinetics, regeneration efficiency, and long-term stability for large-scale industrial settings. Hence, future studies should focus on enhancing fiber properties for sustainable industrial applications, high-performance, and multifunctionality through a promising hybrid modification technique that will bridge the gap into large industrial implementation.