• Journal of Advanced Marine Engineering and Technology
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• v.9 no.3
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• pp.240-249
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• 1985

This paper presents the results of the galvanic anode's characteristicsin the Al-Zn-In-Mg and Al-Zn-In-Mg system anodes used aluminium ingot of low purity, 99.5% grade. The results of thses performance tests are as follows: 1) Zn, In and Mg are an available elements to improve the performance of Aluminium alloy anodes. 2) When the range of zinc content in the Al-Zn-In-Mg system anode is 2-5% the more zinc content, the more improve the anode performance. 3) Al-Zn-In-Mg system anode requires a long term over 50 days for the performance test. 4) The composition of Al-Zn-In-Mg system anode which shows the most excellent performance is Al-(2-3%) Zn-(0.02%) In-(1.0%) Mg. 5) When the Al-Zn-In-Mg system anode is annealed for an hour in 500 to 550 .deg. C, the anode performance is improved. 6) The lower average potential and the better corrosion pattern in the Al-Zn-Mg, Al-Zn-In and Al-Zn-In-Mg system anodes, the more current efficiency is improved.

• Journal of Korea Foundry Society
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• v.24 no.6
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• pp.340-346
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• 2004

The plan for obtaining a good combination of strength and castability appeared feasible and the following observations were made. 1. In Al-12Mg-6.6Zn-xSi alloys, more primary $Mg_2Si$ phase formed with reduced $Al_3Mg_2$ phase, as Si content is necessary for an effective solution heat treatment because the solidus temperature is very low silicon contents. 2. A high tensile strength could be obtained in the heat-treated Al-12Mg-5.5Zn-5Si alloy attributed in the heat-treated Al-12Mg-5.5Zn-5Si alloy attributes to fine $MgZn_2$ particles that precipitated uniformly in the matrix. 3. Al-12Mg-5.5Zn-Si alloys showed excellent casting capabilities such as hot cracking resistance and fluidity compared to the reference commercial alloys. 4. The wear resistance of Al-12Mg-5.5Zn-5Si alloy was superior to that of A7075 alloy, and even higher resistance is expected if the morphology and size of primary $Mg_2Si$ phase is carefully controlled.

• Journal of Korea Foundry Society
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• v.30 no.4
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• pp.137-141
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• 2010

The effects of Zn amounts on the castability and tensile properties of Al-Zn-Mg-Cu alloys were investigated for development of high strength die casting aluminium alloys. Al-Zn-Mg-Cu alloys with 3.5% Zn showed high cast cracking tendency and poor mold filling behaviour. Al-Zn-Mg-Cu alloys with 5wt% Zn and 7wt% Zn had the tensile strengths of 300~400MPa and the elongations of 2~18%. The effect of Zn on the tensile strength of Al-Zn-Mg-Cu alloys was insignificant, but Al-Zn-Mg-Cu alloy with high Zn amount had lower elongation.

• Journal of the Korean Vacuum Society
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• v.19 no.5
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• pp.385-390
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• 2010

We studied the optical characteristics of ZnO:Al and $Al_2O_3$ coated ZnO nanorods. When ZnO:Al is deposited around the undoped ZnO nanorods, thermal diffusion of Al into ZnO gives rise to decrease the binding energy of neutral donor bound exciton whereas an insulating Al2O3 is coated around ZnO, we found that semiconducor-insulator interface states play an important role in optical quenching.

• Journal of the Korean Society for Heat Treatment
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• v.36 no.4
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• pp.198-205
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• 2023

We investigated the effects of Al and Mg on the microstructure and hardness of the coating layer of galvanized steel sheets, by thermodynamic calculations, X-ray diffraction, scanning electron microscopy, and Vickers hardness tests of Zn-0.2Al, Zn-6Al-2Mg, and Zn-10Al-5Mg coating layers. Regardless of the alloy composition of the galvanizing bath, a Fe-Al layer was observed between the coating layer and steel sheet. The Zn-0.2Al coating layer consists of major h.c.p. Zn phase and minor f.c.c. Al phase. The fraction of f.c.c. Al phase (containing a significant amount of Zn) of the coating layer increases with increasing the chemical composition of Al of the galvanizing bath. The h.c.p. MgZn₂ phase was formed in the Al/Mg-containing Zn-6Al-2Mg and Zn-10Al-5Mg coating layers, forming Zn-Al-MgZn₂ eutectic microstructure. The primary MgZn₂ phase was additionally formed in the Zn-10Al-5Mg coating layers containing high concentrations of Al and Mg. The Vickers hardness values of Zn-0.2Al, Zn-6Al-2Mg, and Zn-10Al-5Mg coating layers were 59.1 ± 1.2 HV, 161.2 ± 5.7 HV, and 215.5 ± 40.3 HV, respectively. The addition of Al and Mg increased the hardness of the coating layer by increasing the fraction of the Al phase (containing Zn) and MgZn₂ intermetallic compound, which were harder than the Zn phase.

• 한국신재생에너지학회:학술대회논문집
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• 2005.11a
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• pp.568-571
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• 2005

Highly transparent ZnO films with low resistivity for thin film solar cell applications were fabricated at low temperature by rf magnetron sputtering. Al-doped ZnO films were deposited on glass substrates at a substrate temperature of $200^{\circ}C$. electrical and optical properties of the ZnO:Al films were investigated in terms of the reparation conditions. The transmittance of the ZnO:Al films in the visible range is 90 %. The lowest resistivity of the ZnO:Al films is about $5.7\times10^{-4}$ $\Omega$ cm at the Al content of 2.5 wt% with the film thickness of 500 nm. After deposition, the smooth surface of ZnO:Al films were etched in diluted HCl (0.5%) to investigate the variation of electrical and surface morphology properties due to an textured surface.

• Journal of the Korean Ceramic Society
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• v.32 no.1
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• pp.106-112
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• 1995

In order to examine the effect of CuO and Al2O3 addition on the electrical conductivity of ZnO, both Al2O3 (0, 1, 2, 5, 10at.%) and CuO (1, 5at.%) were added to ZnO. Al2O3 addition (~2at.% Al) increased the total electrical conductivity of ZnO which was already decreased by CuO doping effect Above solid solubility of Al (~2at.%), ZnAl2O4 formed and the total electrical conductivity decreased due to the decrease of sintered density. Impedance measurements were used to know the reason and degree of contribution of three resistive elements, ZnO grain, ZnO/CuO, and ZnO/ZnO grain boundaries, to the total electrical conductivity changed.

• Korean Journal of Materials Research
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• v.16 no.7
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• pp.449-454
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• 2006

Al-doped zinc oxide (ZnO:Al) films for transparent electrodes in thin film solar cells were deposited on glass substrates at a low temperature of $200^{\circ}C$ by rf magnetron sputtering. The transmittance of the ZnO:Al films in the visible range was 87%. The lowest resistivity of the ZnO:Al films was about $5.8{\times}10^{-4}{\Omega}$ cm at the Al content of 2.5 wt%. After deposition, the surface of ZnO:Al films were etched in dilute HCl (0.5%) for the investigation of the change in the electrical properties and the surface morphology due to etching.

• Journal of the Korean Ceramic Society
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• v.19 no.4
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• pp.287-292
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• 1982

Nonohmic properties of ZnO ceramics with various small amounts of additives were studied in relation to experimental methods, additive contant and sintaring temperature. The kinds of additives used to following chemicals were basic additives ($0.5Bi_2O_3$, $0.3BaCO_3$, $0.5MnCO_3$, $0.5Cr_2O_3$, $0.1KNO_3$), $TiO_2$ and $Al(OH)_3$. Expecially, this study has focused on the effectsof $TiO_2$ and $Al(OH)_3$ in ZnO ceramics with the basic additives. SEM studies indicated that the addition of TiO2 promoted grain growth but retarded grain growth with the addition of $Al(OH)_3$. Also, in the case of calcination of ZnO with $TiO_2$ and ZnO with $Al(OH)_3$ previously, grain size of ZnO with $TiO_2$ was larger and that of ZnO with Al(OH)3 was smaller in comparison to the case with out calcination. From the viewpoint of nonohmic exponent and nonohimic resistance, electrical characteristics of ZnO, $TiO_2$ and the basic additives was more effective than that of ZnO, $Al(OH)_3$ and the basic additives. Nonohmic exponent and nonohmic resistance of ZnO, $TiO_2$ and the basic additives was 11-13 and 40-65 respectively.

• Journal of the Korean Society for Heat Treatment
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• v.12 no.1
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• pp.1-8
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• 1999

This study has investigated the effect of aging treatment on the microstructure and mechanical properties of Mg-6Al-xZn(x = 1.5, 2.5) alloys fabricated by the squeeze casting process. The microstructures of as-squeeze cast were composed of pro-eutectic ${\alpha}$, super saturated ${\alpha}$ and ${\beta}(Mg_{17}Al_{12})$ compound. Aged at both $200^{\circ}C$ and $240^{\circ}C$, Mg-6Al-xZn alloys showed the peak hardness due to the formation of ${\beta}(Mg_{17}Al_{12})$ precipitates. The discontinuous precipitates of the lamella type are predominant at $200^{\circ}C$ aging treatment, while the finely dispersed continuous precipitates were dominant at $240^{\circ}C$ aging treatment. Mg-6Al-xZn alloys fabricated by the squeeze casting process had the better combination of tensile strength and elongation compared to the conventionally cast alloys. As zinc contents increased, the tensile strength was increased by the solid solution strengthening effect of zinc.