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The inhibitory effect of some Schiff bases viz. N,N′-bis(2-hydroxybenzylidene)-1,3-diaminobenzene (SB1), N,N′-bis(4-bromobenzylidene)-1,3-diaminobenzene (SB2) and N,N′-bis(2-hydroxy-5-bromobenzylidene)-1,3-diaminobenzene (SB3) on the corrosion of aluminium alloy in 0.5 M HCl acid have been studied using weight loss measurements, potentiodynamic polarization and Scanning Electron Microscopy (SEM). The experimental results showed that these Schiff bases SB1, SB2 and SB3 efficiently inhibit the corrosion of aluminium alloy in 0.5 M HCl medium and found to follow almost similar corrosion inhibition pattern. The potentiodynamic polarization curves revealed that, all the studied Schiff bases are mixed type inhibitors with a predominantly cathodic action and their inhibition efficiencies increased with increasing inhibitor concentration. The adsorption of Schiff bases was found to follow Langmuir adsorption isotherm. SEM study revealed that these compounds protect the metal corrosion by adsorption on its surface to form a protective layer. The inhibition performance depends strongly on the type of functional groups substituted on the benzene ring.

Plasma electrolytic oxidation (PEO) coatings were formed on aluminium alloy in additive Al₂O₃- and TiO₂-containing Na₂SiO₃-based electrolytes, respectively. The effect of these additives on morphology, composition and wearing properties of coatings was investigated. The morphology and composition of coatings were studied by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). Analysis of wearing properties of coatings were done by friction and wearing experiment. It was found that the use of additives greatly affects the surface morphology of coatings. It is shown that the content of $\alpha$-Al₂O₃ in coatings formed in Al₂O₃-containing electrolytes increased with the addition of Al₂O₃. However, the content of $\alpha$-Al₂O₃ in coatings formed in TiO₂-containing electrolytes first increased and then decreased. Among these coatings, the coating formed in silicate-based electrolytes system containing 7g/L Al₂O₃ showed the most superior wearing properties.

Zinc-coated steel wires (1–5 numbers) reinforced in LM6 matrix composites have been prepared by squeeze casting process. Microstructure, hardness, tensile strength, ductility and dry sliding wear behavior of composites have been investigated by varying sliding distance and load. Fracture surface of tensile specimens and worn out surface of wear samples have been examined using field emission scanning electron microscope (FESEM). The results reveal that hardness of composites increased with increasing distance from matrix to steel wires. Maximum hardness values of 751 VHN and 611 VHN are observed in steel wire and at the interface of steel wire — aluminium, respectively. Tensile strength of composites increased upto 24% by reinforcing three steel wires in matrix. During the wear test, weight loss, wear rate and coefficient of friction decreased with increasing number of wires embedded in matrix and increased with increasing sliding distance and load. LM6 aluminium alloy reinforced with five numbers of steel wires decreased the weight loss upto 17% as compared to matrix under 40N load and a sliding distance of 2000m. Fracture surface of tensile specimen shows dimple formation in matrix and broken wires are observed in composites. Worn surface of composites shows fine grooves, whereas delamination is observed in matrix. In general, reinforcement of zinc-coated steel wires in LM6 aluminium alloy exhibited better mechanical properties and wear resistance compared to matrix.

The present work is an effort to study the influence of shot peening on the exfoliation corrosion behavior of aluminium alloy (AA) 5083. Surface textural changes induced by shot peening was characterized using microstructural and X-ray diffraction analysis. The surface roughness parameters were measured to study the benefits of peening induced surface topography. Further, the hardness survey was carried out to assess the severe plastic deformation on the peened layers. As a result, excellent resistance against exfoliation corrosion was achieved in the chloride environment. Shot peening plays major role in enhancing the corrosion resistance of AA 5083. In the absence of exfoliation attack, the unpeened sample surfaces such as ground, milled, and as received conditions end up with a significant pitting attack. The findings of this work will be useful for the aluminium alloy fabrications involved in the marine applications.

This study aims to investigate experimentally and analytically the effects of different machining parameters such as cooling methods and cutting tool materials on surface roughness and chip thickness ratio for milling of AA7075-T6 aluminum alloy. The carbide and high-speed steel (HSS) end mills were used as cutting tools and the conventional, vapor, and compressed air were used as cooling methods in the experiments. The experiment conditions for compressed air at the cutting zone were 6 bar pressure and 30m/s speed flow rate. A mixture of boron oil and water (1/20 mixture ratio) was used as cutting fluid in conventional cooling. The study was carried out using three levels of feed rates (20, 40, 80mm/min), rotational speeds (780, 1330, 2440rpm), and a constant 2mm deep cut. As a result of the experiments, the surface roughness values increased with the increasing levels of feed rate. Besides surface roughness values decreased with increasing levels of the rotational speed. In addition, a better surface quality was obtained in milling processes by using carbide cutting tools compared to HSS tools. It was concluded that the most important parameter affecting the surface roughness and chip thickness ratio is feed rate and the rotational speed, respectively. Better surface roughness and chip thickness ratio were obtained from the vapor processing than the conventional and compressed air.

This work aims to develop a mathematical model and predict the machining performance characteristics of electric discharge machining (EDM) process using response surface methodology (RSM) coupled with desirability function approach (DFA). The effect of various factors, such as electrode material, pulse current, pulse ON time and pulse OFF time were selected as input process parameters with an objective to maximize the material removal rate (MRR), minimize the surface roughness (SR) and electrode wear ratio (EWR). The machining was conducted on Al-Zn-Mg-Cu (AA7075) alloy composite reinforced with 10wt.% TiO₂ particulates produced by stir casting route. The experimental work was planned as per L27 orthogonal array using design of experiments through RSM. Experimental results show that, pulse current and pulse ON time are the most significant factors for MRR and SR while electrode materials and pulse current have notable effect on EWR. Finally, multi-response optimization was performed to predict the EDM parameters by using DFA. The optimum combination of parameters were identified as electrode material (Br), pulse current (15 amps), pulse ON time (900$\mu$s) and pulse OFF time (30$\mu$s).

Electrical Discharge Machining (EDM) is considered as the much traditional, adaptable and unconventional machining process that is proficient in generating complicated structures. Further, it is self-sufficient over the mechanical properties of workpiece materials only if it is conductive. The viability of the EDM process regarding the application types might get considerably improved with the constant enhancement in the personification of numerical control and the metal removal efficacy. This survey intends to make a review of 65 papers related to the optimization and modeling of EDM process machining. The analysis is thus made with regards to the following factors like Al alloy composite in Die Shrinking EDM, Optimization and Al metal matrix composites. Particularly, the hybrid optimization models in various papers are analyzed concerning their logic. Further, the algorithmic and parametric analysis is also made with the contributed papers. Finally, the research gaps and challenges in this EDM processing are discussed, which would pave the way for efficient research works in this area.

This research focuses on investigating the impact of mechanical vibration on the solidification process. Previous studies have indicated that solidification plays a crucial role in enhancing the mechanical properties of materials. By incorporating mechanical vibration technology into the solidification process, the quality of castings can be improved by achieving a more uniform microstructure and reducing grain size. In today’s industrial landscape, striving for excellence involves minimising casting defects to zero and enhancing mechanical characteristics. To comprehend the enhancement in microstructure and mechanical properties of castings, this experimental study examines the influence of mechanical mould vibration on the solidification of A356 alloy. The casting process involves a frequency of 50Hz. To evaluate the effect of vibration during casting, a comparison is made between a casting without mould vibration and its corresponding mechanical properties. The experimental results clearly demonstrate that employing a vibrating mould during casting leads to grain refinement and a significant improvement in hardness when compared to castings produced without the utilisation of a vibrating mould.

Electrical Discharge Machining (EDM) is considered as the much traditional, adaptable and unconventional machining process that is proficient in generating complicated structures. Further, it is self-sufficient over the mechanical properties of workpiece materials only if it is conductive. The viability of the EDM process regarding the application types might get considerably improved with the constant enhancement in the personification of numerical control and the metal removal efficacy. This survey intends to make a review of 65 papers related to the optimization and modeling of EDM process machining. The analysis is thus made with regards to the following factors like Al alloy composite in Die Shrinking EDM, Optimization and Al metal matrix composites. Particularly, the hybrid optimization models in various papers are analyzed concerning their logic. Further, the algorithmic and parametric analysis is also made with the contributed papers. Finally, the research gaps and challenges in this EDM processing are discussed, which would pave the way for efficient research works in this area.