• 한국주조공학회지
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• 제31권2호
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• pp.66-70
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• 2011

Hot dip aluminizing (HDA) is widely used in industry for improving corrosion resistance of material. The formation of intermetallic compound layers during the contact between dissimilar materials at high temperature is common phenomenon. Generally, intermetallic compound layers of $Fe_2Al_5$ and $FeAl_3$ are formed at the Al alloy and Fe substrate interface. In case of cast iron, high contact angle of graphite existed in the matrix inhibits the formation of intermetallic compound layer, which carry with it the disadvantage of a reduced reaction area and mechanical properties. In present work, the process for the removal of graphite existed on the surface of specimen has been investigated. And also HDA was proceeded at $800^{\circ}C$ for 3 minutes in aluminum alloy melt. The efficiency of graphite removal was increased with the reduction of particle size in sanding process. Graphite appears to be present both in the region of melting followed by re-solidification and in the intermetallic compound layer, which could be attributed to the fact that the surface of cast iron is melted down by the formation of low melting point phase with the diffusion of Al and Si to the cast iron. Intermetallic compound layer consisted of $Fe(Al,Si)_3$ and $Fe_2Al_5Si$, the layer formed at cast iron side contained lower amount of Si.

• 한국재료학회지
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• 제18권3호
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• pp.153-158
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• 2008

Fe-aluminides have the potential to replace many types of stainless steels that are currently used in structural applications. Once commercialized, it is expected that they will be twice as strong as stainless steels with higher corrosion resistance at high temperatures, while their average production cost will be approximately 10% of that of stainless steels. Self-propagating, high-temperature Synthesis (SHS) has been used to produce intermetallic and ceramic compounds from reactions between elemental constituents. The driving force for the SHS is the high thermodynamic stability during the formation of the intermetallic compound. Therefore, the advantages of the SHS method include a higher purity of the products, low energy requirements and the relative simplicity of the process. In this work, a Fe-aluminide intermetallic compound was formed from high-purity elemental Fe and Al foils via a SHS reaction in a hot press. The formation of iron aluminides at the interface between the Fe and Al foil was observed to be controlled by the temperature, pressure and heating rate. Particularly, the heating rate plays the most important role in the formation of the intermetallic compound during the SHS reaction. According to a DSC analysis, a SHS reaction appeared at two different temperatures below and above the metaling point of Al. It was also observed that the SHS reaction temperatures increased as the heating rate increased. A fully dense, well-bonded intermetallic composite sheet with a thickness of $700\;{\mu}m$ was formed by a heat treatment at $665^{\circ}C$ for 15 hours after a SHS reaction of alternatively layered 10 Fe and 9 Al foils. The phases and microstructures of the intermetallic composite sheets were confirmed by EPMA and XRD analyses.

• Bulletin of the Korean Chemical Society
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• 제29권9호
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• pp.1787-1789
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• 2008

• 한국주조공학회지
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• 제31권2호
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• pp.83-86
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• 2011

Ni-Al based intermetallic compounds of self-propagating high-temperature synthesis (SHS) by the heat of molten aluminum and been coated on the aluminum casting alloy. The effects of the pouring temperature in casting and the thickness of casting substrate on SHS of the coating layer have been investigated. The experimental result showed that the reaction of the coating layer was activated with increasing the pouring temperature in casting and the thickness of casting substrate. However, the aluminum substrate was re-melted by the heat of formation for intermetallic compounds. Then, it was considered that some mechanical or thermal treatments for elemental powder mixtures were required to control the heat of formation for intermetallic compounds in advance.

• 한국표면공학회지
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• 제34권3호
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• pp.206-214
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• 2001

The purpose of this study is to determine the effects of Ni on precipitate formation in a Ni added galvanizing bath, which has various Ni content from 0.03wt.% to 0.5wt.%. The addition of hi in the Ni containing galvanizing bath resulted in the formation of Al-Ni intermetallic compounds such as $Al_3$$Ni_2$ and $Al_2$Ni, which make up most of the top precipitates. At 0.07wt.%Ni, Al-Ni intermetallic compound formed sensitively with small amount of Al addition. By analysing the reaction thickness of galvanized steel, it was found that Ni addition in a Zn-0.18w1.%Al bath tended to suppress the formation of Fe-Zn intermetallic compounds but the formation of these compounds increased with increasing Ni concentration above 0.1wt.%.

• 한국표면공학회지
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• 제35권1호
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• pp.47-52
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• 2002

Intermetallic compound on the soldered interface plays important role on the bondability and mechanical properties of soldered joint. The formation of intermetallic compounds are influenced by many factors such as temperature, holding time, base metals and so on. On this study the effect of number of reflow times on the intermetallic growth was investigated. For the experimental materials, Sn-3.5Ag-0.7Cu solder ball of 0.3mm diameter and RMA-type flux were used. Thickness of intermetallic compound of solder ball by 2nd reflow showed nearly 60% higher than that of 1st reflow, and shear strength showed 10% higher value. Thickness and shear strength according to the position of interface such as upper side or lower side between two substrates were also investigated.

• 한국표면공학회지
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• 제22권1호
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• pp.3-9
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• 1989

The intermetallic compount formation, growth rections, and growth kinetices as functions of the aging temperaturess, time, and the condition of substarte have invedtigted in the Sn/Cu and Sn/Ni bimetal couples. The η'-phase (Cu6Sn5) and $\delta$-phase (Ni3Sn4) were only found to grow at 20 and $70^{\circ}C$in the Sn/Cu and Sn/Ni bimetallic coples repectively. Above that temperatures, all other compounds were formed in sequence of high Sn content plase and the metastable Cu41Sn11 was formed at agend $200^{\circ}C$. The ectivation energy for the growth of intermetallic compounds was 14.7Kxal/mole in the Sn/Cu interface and 26.7Kcal/mole in the Sn/Ni interface.

• 한국재료학회지
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• 제12권9호
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• pp.696-700
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• 2002

The Ti-aluminide intermetallic compound was formed from high purity elemental Ti and Al foils by self-propagating, high-temperature synthesis(SHS) in hot press. formation of $TiAl_3$ at the interface between Ti and Al foils was controlled by temperature, pressure, heating rate, and so on. According to the thermal analysis, it is known in this study that the heating rate is the most important factor to form the intermetallic compound by this SHS reaction. The V layer addition between Al and Ti foils increased SHS reaction temperatures. The fully dense, well-boned inter-metallic composite($TiA1/Ti_3$Al) sheets of 700 m thickness were formed by heat treatment at $1000^{\circ}C$ for 10 hours after the SHS reaction of alternatively layered 10 Ti and 9 Al foils with the V coating layer. The phases and microstructures of intermetallic composite sheets were confirmed by EPMA and XRD.

• 마이크로전자및패키징학회지
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• 제9권2호
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• pp.1-9
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• 2002

실제 BGA패키지에서 Sn-Ag-(Cu) 솔더와 금속패드가 반응하여 생성된 금속간 화합물의 특성을 Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS)f) X-ray Diffractometer (XRD)를 사용하여 분석하였다. EDS로 분석한 결과를 보면 BGA 패키지에서 Sn-Ag-Cu 솔더와 Au/Ni/Cu 금속층간의 반응으로 생성된 금속간화합물은 $(Cu,Ni)_6Sn_5$로 예상되며 . Cu의 편석은 솔더와 Ni 층 사이에서 발견되었다. XRD 분석결과 Cu를 함유하고 있는 Sn-Ag-Cu 솔더와 Ni층 사이에서는 $\eta -Cu_6 Sn_5$ 타입의 금속간화합물이 분석되었으며 Sn-Ag 솔더와 Ni층 사이에서는 $Ni_3$Sn_4$가 분석되었다. 계면에 생성된 금속간화합물은 리플로 회수와솔더내의 Cu의 함량에 따라증가하였다

• Journal of Welding and Joining
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• 제31권5호
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• pp.64-70
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• 2013

The joining of Ti and SUS304 dissimilar metals is one of the effective measures to save rare metal. But Ti and SUS304 have differences in materials properties, and Ti and Fe intermetallic compounds such as TiFe and $TiFe_2$ are easily formed in weld fusion zone between Ti and SUS304. Nevertheless, in this study, full penetration lap dissimilar welding of Ti and SUS304 using single-mode fiber laser with ultra-high welding speed was tried, and it was found out that ultra-high welding speed could control the generation of intermetallic compound. To recognize the formation of intermetallic phase in the weld fusion zone and the compound zone of interface weld area were observed and analyzed using energy dispersive X-ray spectroscopy (EDX). And it was confirmed that the ultra-high welding speed could reduce amount of intermetallic compounds, but the intermetallic compounds were existed in the weld fusion zone under the all conditions.