• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.769-775
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• 2002

The results gained as part of the study on weldability of compositions from steels, aluminium, titanium alloys in various combinations including similar and dissimilar metal bonding variants with reference to solution of specific practical problems are presented in this work. It has been shown that in the case of HIP/DB carried out with direct interaction of bonding surfaces of the most dissimilar material combinations under study, formation of high-quality joints is not assured due to various reasons. That is why development of special bonding techniques was required. The bonding techniques developed and used for HIP/DB of dissimilar steels, "Steel-bronze", "Titanium-niobium"; "Titanium-steel" and other compositions under study ensured vacuum-tight microvoid-free joints strength of a which was equal to the milder parent metal, including those obtained at reduced welding pressures. Examples of new products manufactured by HIP/DB using the technologies developed are presented.

• The Journal of Advanced Prosthodontics
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• 제6권3호
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• pp.215-223
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• 2014

PURPOSE. This study aimed to develop a copper-aluminium-nickel alloy which has properties comparable to that of dental alloys used for dental post and core applications with the reasonable cost. MATERIALS AND METHODS. Sixteen groups of experimental copper alloys with variants of 3, 6, 9, 12 wt% Al and 0, 2, 4, 6 wt% Ni were prepared and casted. Their properties were tested and evaluated. The data of thermal, physical, and mechanical properties were analyzed using the two-way ANOVA and Tukey's test (${\alpha}$=0.05). The alloy toxicity was evaluated according to the ISO standard. RESULTS. The solidus and liquidus points of experimental alloys ranged from $1023^{\circ}C$ to $1113^{\circ}C$ and increased as the nickel content increased. The highest ultimate tensile strength ($595.9{\pm}14.2$ MPa) was shown in the Cu-12Al-4Ni alloy. The tensile strength was increased as the both elements increased. Alloys with 3-6 wt% Al exhibited a small amount of 0.2% proof strength. Accordingly, the Cu-9Al-2Ni and Cu-9Al-4Ni alloys not only demonstrated an appropriate modulus of elasticity ($113.9{\pm}8.0$ and $122.8{\pm}11.3$ GPa, respectively), but also had a value of 0.2% proof strength ($190.8{\pm}4.8$ and $198.2{\pm}3.4$ MPa, respectively), which complied with the ISO standard requirement (>180 MPa). Alloys with the highest contents of nickel (6 wt% Ni) revealed a widespread decolourisation zone (5.0-5.9 mm), which correspondingly produced the largest cell response, equating positive control. CONCLUSION. The copper alloys fused with 9 wt% Al and 2-4 wt% Ni can be considered for a potential use as dental post and core applications.

• 한국주조공학회지
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• 제18권4호
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• pp.357-363
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• 1998

Microstructure of A356 aluminium alloys cast in a permanent mold was investigated by optical microscope and image analyzer, with particular respect to the shape and size distribution of iron intermetallics known as ${\beta}-phase$ ($Al_5FeSi$). Morphologies of the ${\beta}-phase$ was found to change gradually with the Be:Fe ratio like these. In Be-free alloys, ${\beta}-phase$ with needlelike morphology was well developed, but script phase was appeared when the Be:Fe ratio is above 0.2:1. With the Be:Fe ratios of 0.4:1-1:1, script phase as well as Be-rich phase was also observed. In case of higher Be addition, above 1:1, Be-rich phase was observed on all regions of the specimens, and increasing of the Be:Fe ratios gradually make the Be-rich phase coarse. It was also observed that the ${\beta}-phase$ with needlelike morphology was coarsened with increase of the Fe content in Be-free alloys. However, in Be-added alloys, length and number of these ${\beta}-phases$ were considerably decreased with the increased Be:Fe ratio. It was concluded that Fe impurity element to be crystallized into needlelike intermetallics was tied up by Be addition element, and new phases were crystallized into script or Be-rich intermetallics.

• 한국주조공학회지
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• 제7권4호
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• pp.342-347
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• 1987

• Journal of Welding and Joining
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• 제19권6호
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• pp.584-590
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• 2001

• Journal of Welding and Joining
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• 제19권2호
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• pp.160-166
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• 2001

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1999년도 특별강연 및 춘계학술발표대회 개요집
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• pp.50-53
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• 1999

• Journal of Welding and Joining
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• 제12권2호
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• pp.64-75
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• 1994

• 한국주조공학회지
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• 제9권5호
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• pp.386-388
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• 1989

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1037-1038
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• 2006

The increasing demand of PM parts for automobile and aerospace applications has caused a strong development of the aluminium based metal matrix composites (MMCs).Aluminium alloys are one of most widely used materials as matrix in MMCs, both in research and development as well as in industrial applications. In the present work, the influence of the ceramic reinforcement addition to a 2xxx series aluminium alloy is studied. Several percentages of TiCN have been added to the Al-Cu alloy using PM techniques, in order to analyze its influence on the liquid phase sintering process and on the final properties of the material.