• Journal of the Korean institute of surface engineering
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• v.30 no.1
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• pp.44-56
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• 1997

Influence of electrochemical etching conditions on capacitance gain of aluminium electrolytic on capacitor foil has been investigated by etching cubic textured high purity aluminum foil in dilute hydrochloric acid. Uniformly distributed etch pit tunnels on aluminum surface have been obtained by pretreatment aluminium foil in 10% NaOH solution for 5 minutes followed by electrochemical etching. Electrostatic capacitance of etched aluminium foil anodized to high voltage increased with the increase of current density, total charge, temperature and concentration of electrolyte up to maximum CV-value and then deceased. Election optical observation of the etched foil revealed that the density of etch of etch pits increased with the increase of current density and concentration of electrolyte. this increase of etch pit density enlarged of the increase of capacitance. However, abnormal high current density and high electrolyte concentration induced the local dissolution of the foil surface which resulted the decrease of foil capacitance.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.498-501
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• 2001

Blanking is one of the most frequently used processes in sheet metal forming. In this paper, attention is paid to the blanking simulation of aluminium foil with $20{\mu}m$ thickness which is used an anode in lithium-ion polymer battery. In order to study the shearing mechanism for the metallic foil, finite element analysis with Crockroft and Latham fracture criterion was performed. The objective of the present work is to evolve a methodology to obtain the optimum punch-die clearance for a given aluminium foil by the simulation of the blanking process using a general purpose FEM code.

• 한국전기화학회:학술대회논문집
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• 2001.04a
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• pp.22-22
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• 2001

• 한국전기화학회:학술대회논문집
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• 2002.04a
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• pp.26-26
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• 2002

• 한국전기화학회:학술대회논문집
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• 2003.04a
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• pp.43-43
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• 2003

• Journal of Electrochemical Science and Technology
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• v.12 no.1
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• pp.92-100
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• 2021

In this study, the use of waste food grade aluminium foil and mild steel as a sacrificial electrode in an electrocoagulation system was developed to remove reactive red 111 from wastewater. The effect of different parameters like pH, current density, electrode material, and different electrode configurations was investigated. Optimum operating conditions for maximum COD removal were determined as, 6 mA/㎠ current density and 30 min at 5 pH for aluminium foil and 7 pH for mild steel. Maximum COD reduction obtained at optimum conditions using monopolar 4 electrodes, monopolar 2 electrodes and bipolar electrode configuration were 96.5%, 89.3%, and 90.2% for Mild steel as a sacrificial electrode and 92.1%, 84.2%, and 88.6% for aluminium foil as a sacrificial electrode. The consumption of electrode and energy for both the electrodes of different configurations were calculated and compared. Using batch experimental data, a continuous-flow reactor was developed. Sludge analysis using Fourier Transform Infra-Red Spectroscopy (FTIR) analysis was done. Different adsorption kinetic models and isotherms were developed and it was found that pseudo second-order model and Langmuir isotherm fit best with the experimental data obtained.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.338-339
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• 2005

The wider surface of the aluminum foil, electrochemically very important and it is necessary to increase the surface area. A study has been made of the fabrication condition for etching cube texture of high purity aluminium foil and of electrochemical etching of the aluminium foil. In the present work, it is shown there exists a relation between the influence of the pre-treatment time in the NaOH & HCI solution and $H_2SO_4$ concentration in the conversion solution. Also effect of temperature during AC etching was also studied. Result of the etched aluminum film is shown in the typical SEM images. Its electrochemical characteristics were investigated by cyclic voltammetry. And effects of current density and frequency is also reported. Cyclic voltammogram showed that the protective oxide film was formedon the inner surfaces of etch pit. the frequency influence resistance of oxide film in AC etching.

• 연구논문집
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• s.29
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• pp.131-139
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• 1999

The effect of ball milling conditions in the milling of aluminium foil scraps was studied. Initial foil thickness, ball size. content of oleic acid. weight ratio of mineral spirits/foil. charged amount of foil were varied in wet ball milling process. It is impossible to make flake powders by milling of foil scraps with thickness $120 \mum$. As foil thickness decreases from $60\mum$ to $6.5\mum$, Mean size of powder milled for 30 h decreases from 107 µm to 17 µm. Bigger ball is slightly beneficial for milling of foils to the flake powders due to the larger impact energy produced by them. It is impossible to mill the foil without oleic acid to fabricate the flake powder. As content of oleic acid increases from 1.5 % to 5 %, mean size of flake powder milled for 30 h is drastically decreased. For the mineral spirits content below 50 %, foil scrap was not milled because sliding motion of balls by lubricant effect between balls and wall of container. As weight ratio of mineral spirits and foil increase over 100 %, foils were milled powders with mean powder size 15 - 20 때 irrespective of mineral spirits content due to reduced lubricant effect. As charged amount of foil decreases, mean powder size decreases due to increased collision frequency between ball and foil.

• Journal of Soil and Groundwater Environment
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• v.20 no.1
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• pp.36-40
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• 2015

This study examined the disinfection in combined sewer overflows (CSOs) by pulsed ultraviolet (PUV). The reflectors (stainless steel. mirror, aluminium foil, aluminium (1050), aluminium (6061), aluminium (5052), and aluminium mirror) of PUV irradiation was performed in a 90 L stainless reactor at a constant temperature of $20^{\circ}C$ and an applied power of 4000 W. The reflection efficiency of reflectors were showed 1.00 (aluminium mirror) ~ 1.48 (aluminium foil) does. The case of a rough surface analysis using SEM showed high reflectance, was the case of a smooth surface and a low reflectivity. Pseudo first-order rate constant calculated results, has a higher reflectivity values were more than twice as high compared to the low reflectivity. Affected Total coliforms disinfection time, depending on the type of reflector is considered.

• Applied Chemistry for Engineering
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• v.4 no.3
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• pp.497-504
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• 1993

The effect of DCCA (Drying Control Chemical Additives) on the drying of gel was investigated in order to determine an optimum drying condition of mullite precursor through sol-gel process. Aluminium sec-butoxide was synthesized from aluminium foil and then mullite powders were synthesized from Tetra-ethyl-ortho-silicate (TEOS) and the aluminium sec-butoxide. N, N-dimethyl formamide (DMF), Glycerol, 1, 4-Dioxane, and Oxalic acid were used as DCCA. Mullite powders that were calcined at 200, 900, 1100, and $1250^{\circ}C$ for 2hr were analysed by XRD, TG-DTA, FT-IR, and SEM in order to investigate structural change and characteristics of calcined powders. The results of this work showed that the drying time of gel was reduced to about half in the presence of 0.1mol DMF compared with the absence of DCCA and also calcined powders were obtained without remarkable structural change despite of the addition of DCCA.