• 한국생산제조학회지
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• 제21권6호
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• pp.926-931
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• 2012

Rotary bar was cutting tool being in use for deburring scale after welding metal and for eliminating sharp edges. It was necessary to develop exclusive 6-axis machine being possible to process machining continuously for making an cutting edge of rotary bar and to revise easily machining program. This study aimed at the structural analysis of strength according to the configuration of new made 6-axis machine and at the machining accuracy and durability of rotary bar. As a result of test, the runout of new rotary bar manufactured out of 6-axis machine was decreased from 0.385 mm to 0.027mm extensively than old one. And good cutting ability and durability was obtained equal quality compared with imported products.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2010년도 춘계학술발표논문집 2부
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• pp.978-980
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• 2010

Nocolok 브레이징을 이용할 경우 저농도 플럭스와는 달리 고농도 플러스를 이용해 필요한 부분만 도포해야 한다. 일반적으로 고농도 플럭스 도포의 경우 인력을 이용한 수작업을 실시하므로 작업이 비효율적일 뿐만 아니라 플럭스 분진 날림 몇 열 등으로 인해 기피하고 있는 실정이다. 그러므로 경제적이며 효율적인 고농도 플럭스 자동 도포 장치의 개발을 통한 품질 향상 및 생산 단가 저감 등이 절실한 실정이다. 본 연구에서는 고농도 플럭스 자동 도포 시스템을 제작을 위해 수치해석을 이용한 고농도 플럭스 혼합 탱크의 혼합 효율성 및 정수압력을 이용한 유량 분배 해석을 실시하였다.

• 한국레이저가공학회:학술대회논문집
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• 한국레이저가공학회 2006년도 춘계학술발표대회 논문집
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• pp.25-30
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• 2006

최근 차체 용접의 고속화를 통한 생산성 향상 및 차체 설계의 자유도 향상, 차체 강성 증가를 목적으로 원격 용접, 브레이징 등 다양한 형태로 레이저 적용 기술이 개발되고 있다. 뿐만 아니라, 레이저의 종류에 있어서도 $CO_2$ 레이저, Nd:YAG 레이저, 화이버 레이저, 디스크 레이저등 다양한 형태의 레이저가 사용되고 있으며, 사용자의 목적에 부합하는 여러 형태의 레이저들이 개발되고 있다. 본 연구는 $CO_2$ 레이저 원격 용접의 차체 T/GATE 양산 적용 결과를 바탕으로, 적용 용접점 선정, 용접품질 확보, 생산성 향상을 위한 공정의 최적화 요소들에 대한 개발을 진행하였다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2005년도 춘계학술발표대회 개요집
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• pp.48-50
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• 2005

Advanced hard materials based on diamond are in common use. In this study our main goal was employed to analyze, the mechanisms for the rich phases and chromium carbide, interface of a diamond grits brazed to a Ni-based brazing filler metal matrix. When Ni-7Cr-3Fe-3B-4Si (wt. %) was utilized as the brazing alloy, an isothermal holding resulted in the various products(Ni-rich/Cr-rich domains, carbide). According to these results, the chemical compounds and chromium carbides products is considered to play an important role in brazing temperature and time. Especially chromium carbide has an influence on brazing junction properties.

• Journal of Welding and Joining
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• 제34권2호
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• pp.36-45
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• 2016

Recent developing tendency for technologies of high efficient brazing are studied by searching of NDSL, Science Direct, KIPRIS, PCT and so on. Active metal brazing, arc brazing, fluxless brazing, brazing with low melting point, reactive air brazing, laser brazing, laser droplet brazing are investigated. By optimal selecting of the above mentioned technologies, it needs to investigate an economical metallurgical design and the advanced brazing methods. To improve the embrittlement of intermetallic compound at brazing interface, it must be studied the inexpensive variant metals including nonmetals and the heat sources(MIG, TIG, Laser) by hybrid techniques.

• Journal of Welding and Joining
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• 제32권1호
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• pp.66-70
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• 2014

In Ti active brazing of YSZ to STS 430 using Ag-Cu Filler Metal, the effect of Ti contents on the shear bonding strength were investigated together with the effect of brazing temperature and holding time. The addition of Ti in Ag-Cu Filler Metal increased the bonding strength up to 4.68% Ti, followed by the decrease with further addition. This seems to be caused by formation of TixOy at the reaction layer. Brazing temperature was optimized at $960^{\circ}C$ among a given temperature ranges. The addion of Sn to Ag-Cu filler metal brought the decrease of its melting temperature its melting temperature without a significant decrease of bonging strength.

• 한국주조공학회지
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• 제30권5호
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• pp.187-195
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• 2010

In this study, in order to obtain a useful guide line for design and production of automotive heat exchanger components made of 4343/3003/4343 aluminum clad sheets, it was aimed to improve the understanding about the grain refinement effect on brazing characteristic of the clad sheets. Al-10Ti master alloy was used for grain refinement of 3003 core alloy, and the Ti inoculation level was systematically changed up to 0.1 wt%. The three-layer aluminum clad sheets were fabricated by hot roll bonding process. The effect of grain refinement on brazing characteristic of the clad sheets was investigated by evaluating wettability, bonding strength and sagging resistance.

• 한국세라믹학회지
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• 제33권9호
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• pp.1045-1049
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• 1996

Pressureless-sintered polycrystalline alumina and carbon steel were joined with Ag-33.5Cu-1.5Ti (wt%) brazing alloy. SEM observation revealed that two reaction layers with different thicknesses were continuously formed between the alumina and the brazing alloy. A thick layer formed on the brazing alloy side was identified as Ti3(Cu0.93Al0.07)3O phase with diamond cubic structure. Another thin layer adjacent to the alumina was revealed as $\delta$-TiO phase of which the crystal structure was HCP with a lattice parameter of a0=0.419 nm and c0=0.284 nm. It was confirmed using XPS analysis that $\delta$-TiO was formed directly by a redox reaction of alumina with titanium ir, molten brazing alloy.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.229-234
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• 2007

Microscale heat transfer and microfluidics have become increasingly important to overcome some very complex engineering challenges. The use of very small passages to gain heat transfer enhancement is a well documented method for achieving high heat flux dissipation. As the passage size is decreased, the heat transfer performance increases but the pressure drop increases sharply when the passage size is reduced. In this study, the performance evaluation of micro plated heat exchangers under the counter flows with straight, V-shaped and Y-shaped channel are carried out.

• Journal of Welding and Joining
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• 제7권2호
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• pp.12-24
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• 1989

천이액상확산접합법은 접합계면에 일시적으로 액상이 형성되기 때문에, 고상확산접합법과 비교 하여 비교적 쉽게 금속결합을 이룰 수 있을 뿐만 아니라, 정밀하게 표면을 가공할 필요가 없으 며, 접합압력이 거의 필요 없다는 것이 잇점이라고 할 수 있다. 도한, 접합온도에서 등온응고되 기 때문에, 브레이징법과 비교하여 접합계면에 취약한 금속간화합물(Metallic Compound)이 생 성되지 않으므로, 기계적성질 및 내식성이 우수한 접합이음부를 얻을 수 있다는 잇점이 있다. 따라서, 본 접합법은 원리적으로 모재(Base Metal)와 거의 같은 정도의 물리적, 화학적, 기계적 성질을 갖는 접합이음부(Joint or Bonded Interlayer)를 얻을 수 있는 접합법이라고 생각되어진 다. 본 해설에서는 천이액상확산접합법의 기본원리, 접합기구, 접합인자 및 실용된 예에 대해서 서술하고자 한다.