알루미늄의 브레이징과 원리

이순재,정도현,정재필 한국마이크로전자및패키징학회 2017 마이크로전자 및 패키징학회지 Vol.24 No.4

Aluminum alloys have been widely used in many fields such as electronic, structure, aero-space and vehicle industries due to their outstanding thermal and electrical conductivity as well as low cost. However, they have some difficulties for using in brazing process because of the strong oxide layer of Al2O3 on the surface of Al alloy. In addition, their melting point is similar to that of brazing filler metal resulting in thermal damage of Al alloys. Therefore, it is very important to understand the brazing principles, filler metal and its properties such as wetting, capillary flow and dissolution of base metal in the Al brazing process. This paper reviews the brazing principles, aluminum alloys, and brazing fillers. In the case of brazing principle, some formula was used for calculation of capillary force and the dissolution to obtain the best condition of Al brazing. In addition, the advanced research trends in Al brazing were introduced including thermal treatment, additive for improving property and decreasing melting point in Al brazing process.

Current Review on the Research Status of Cemented Carbide Brazing: Filler Materials and Mechanical Properties

Xiaohui Yin,Qunshuang Ma,Bing Cui,Lei Zhang,Xingyan Xue,Sujuan Zhong,Dong Xu 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.4

Cemented carbides have been widely applied in cutting tools and wear-resistant components due to their ultrahigh hardnessand good wear resistance. However, the disadvantages of limited impact toughness and high cost have restricted their furtherapplication. Consequently, cemented carbides are usually joining with ductile steels to combine the advantages of both. Among various materials joining technologies, brazing have been an effective method to achieve high quality dissimilarcemented carbide joints. In this paper, the research status of cemented carbide brazing is reviewed. The materials utilized asbrazing filler metal in cemented carbide brazing joints are summarized in detail. Researchers have done lots of works utilizingCu based and Ag based brazing filler metals which are the most commonly used interlayers in brazed joints of cementedcarbide and ductile steel. The effects of different filler metal on wettability, microstructure, phase constitution and mechanicalproperties of brazed cemented carbides joints are analysed. Besides, a series of newly developed brazing filler materialsuch as nickel-based high temperature brazing filler metal, amorphous brazing filler metal and high entropy alloy brazingfiller materials are also involved. These newly developed brazing filler metals have shown great potential in fabricating highquality joints. Finally, the current issues of cemented carbide brazing are reviewed and the develop trend is predicted.

Laser brazing molybdenum using two titanium base fillers

Lin, Chia-Chen,Lee, Cheng-Han,Shiue, Ren-Kae,Shy, Hsiou-Jeng Techno-Press 2012 Advances in materials research Vol.1 No.3

Brazing Mo using Ti and Ti-15-3 foils has been investigated in the experiment. For traditional furnace brazing, solidification shrinkage voids cannot be completely removed from the joint even the brazing temperature increased to 2013 K and 160 ${\mu}m$ thick Ti foil applied in brazing. Similar results are observed from the joint using Ti-15-3 filler. In contrast, the quality of laser brazed joint is much better than that of furnace brazed joint. A sound joint is achieved after laser brazing. Tensile strengths of 418 and 373 MPa are obtained from laser brazed joints at the power of 800W and travel speed of 5 mm/s using Ti and Ti-15-3 fillers, respectively. All laser brazed joints are fractured at the brazed zone and cleavage dominated fractures are widely observed from their fractographs. The Ti base fillers show potential in laser brazing Mo substrate.

극성가변 AC 펄스 MIG용접기를 이용한 아크 브레이징

조상명,공현상 대한용접접합학회 2003 대한용접·접합학회지 Vol.21 No.4

MIG brazing is used for many parts without melting base metal because of high productivity. Pulsed MIG brazing can be used to further reduce heat input and to improve the process stability. However, a significant amount of zinc in galvanized sheet steel is burned off in the area of brazes. Therefore, the brazing method to reduce the heat input is needed. In the brazing for galvanized sheet steel, variable polarity AC pulse MIG arc brazing can be applied to more decrease the heat input by setting EN-ratio adequately. In this research, we studied for the variable polarity AC pulse MIG arc brazing to decrease the heat input by using ERCuSi-A wire. As the result of increasing EN-ratio, melting ratio of base metal and burning off of zinc were reduced in galvanized sheet steel.

Diffusion Enhancement during Electrically Assisted Brazing of Ferritic Stainless Steel Alloys

Viet Tien Luu,Thi Kieu Anh Dinh,Hrishikesh Das,김주리,홍성태,성현민,한흥남 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.5 No.5

The electrically assisted brazing of a ferritic stainless steel with nickel-based filler metal is experimentally investigated. During electrically assisted brazing of a lap joint, the temperature of the joint is first rapidly increased to a brazing temperature and held nearly constant for a specific period using a pulsed electric current. Microstructural analysis results strongly suggest that the electric current during electrically assisted brazing enhances diffusion between the filler metal and the ferritic stainless steel, thus inducing significantly thicker diffusion zones compared with induction brazing. The mechanical test results show that the strength of the electrically assisted brazing joint is comparable to or even superior to those of the joint fabricated by induction brazing, while the process time of the electrically assisted brazing is significantly shorter than that of induction brazing.

고온 진공 브레이징을 이용한 초경합금과 스테인리스강의 접합 계면 특성

박동환,현경환,권혁홍 한국소성∙가공학회 2020 소성가공 : 한국소성가공학회지 Vol.29 No.6

The cemented carbide and stainless steel were bonded using a hot-vacuum brazing method to analyze the bonding interface. Since it is suitable for the hot vacuum brazing, nickel metal was used as a binder among the main components of the cemented carbide, and a new cemented carbide material was developed by adjusting the alloy composition. The paste, which is one of the important factors affecting the hot vacuum brazing bonding, was able to improve brazing adhesion by mixing solder as Ni powder and a binder as an organic compound at an appropriate ratio. Division of the stainless steel yielded a dense brazing result. This study elucidated the interfacial characteristics of wear-resistant parts by bonding stainless steel and cemented carbide via hot vacuum brazing.

Grain-Structure Evolution of Brazing-Treated A4343/A3003/A4343 Aluminum Brazing Sheets Rolled with Different Reductions

김수현,강주희,어광준,김형욱 대한금속·재료학회 2015 METALS AND MATERIALS International Vol.21 No.2

The grain-structure evolution of three-layered A4343(clad)/A3003(core)/A4343(clad) aluminum brazing sheetswas studied by means of electron backscatter diffraction. Three different samples were prepared by cold rollingwith 17%, 22%, and 44% reduction, and the brazing treatment was carried out in form of differential scanningcalorimetry. Orientation maps of the clad and the core suggested that the grains in the melted and re-solidifiedclad did not grow epitaxially from the core in case of the 17% and 22% cold-rolled samples. In contrast,the grains in the 44% cold-rolled sample seemed to have been formed by epitaxial growth from the core. Kernel average misorientation (KAM) analysis revealed that the samples cold rolled with 17% and 22%reduction retained a deformed microstructure in the core even after the brazing treatment, but the core ofthe 44% cold-rolled sample was composed of coarse elongated grains, free from any substructure. The dissolutiondepth corresponding to the thickness of the core affected by the brazing treatment was proportional tothe average KAM of the core.

Different Attempt to Improve Friction Stir Brazing: Effect of Mechanical Vibration and Rotational Speed

Behrouz Bagheri,Mahmoud Abbasi,Farzaneh Sharif,Amin Abdollahzadeh 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.9

A developed version of friction stir brazing (FSB) entitled friction stir vibration brazing (FSVB) was presented to fabricatelow carbon steel joint using %67wt Sn-%33wt Pb alloy as a braze metal. This attempt aims to analyze the role of mechanicalvibration and rotational speed on microstructure and mechanical behaviors of the brazed samples. Furthermore, the thermalanalysis, the thickness of intermetallic compounds (IMCs) layers, and void volume percentage at the joint interface werestudied. It was concluded that the temperature during the joining process increased and the coherency of the joint interfaceenhanced while FSVB was applied instead of FSB. In addition, the grains in the joint zone under the FSVB process weresmaller than those produced under the conventional FSB process. The results also showed that the mechanical performance,namely hardness, and shear strength increased and the thickness of the IMCs layer along with the void volume percentagein the brazed sample decreased as rotational speed increased from 850 to 1150 rpm. The results indicated that rotationalspeeds over 1150 rpm had detrimental effects on mechanical properties. This is related to the effect of high heat input andinduced temperature on brazing flow and filler-base metal interaction.

Effects of Reactive Air Brazing Parameters on the Interfacial Microstructure and Shear Strength of GDC-LSM/Crofer 22 APU Joints

Raju, Kati,Kim, Seyoung,Seong, Young-Hoon,Yoon, Dang-Hyok The Korean Ceramic Society 2019 한국세라믹학회지 Vol.56 No.4

In this paper, the joining characteristics of GDC-LSM ceramics with Crofer 22 APU metal alloys was investigated at different brazing temperatures and holding times by reactive air brazing. Brazing was performed using Ag-10 wt% CuO filler, at three different temperatures (1000, 1050, and 1100℃ for 30 minutes) as well as for three different holding times (10, 30, and 60 minutes at 1050℃). The interfacial microstructures were examined by scanning electron microscopy and the joining strengths were assessed by measuring shear strengths at room temperature. The results show that with increasing brazing temperature and holding time, joint microstructure changed obviously and shear strength was decreased. Shear strength varied from a maximum of 100±6 MPa to a minimum of 18±5 MPa, depending on the brazing conditions. These changes were attributed to an increase in the thickness of the oxide layer at the filler/metal alloy interface.

Effects of Reactive Air Brazing Parameters on the Interfacial Microstructure and Shear Strength of GDC–LSM/Crofer 22 APU Joints

Kati Raju,Seyoung Kim,Young-Hoon Seong,Dang-Hyok Yoon 한국세라믹학회 2019 한국세라믹학회지 Vol.56 No.4

In this paper, the joining characteristics of GDC–LSM ceramics with Crofer 22 APU metal alloys was investigated at different brazing temperatures and holding times by reactive air brazing. Brazing was performed using Ag–10 wt% CuO filler, at three different temperatures (1000, 1050, and 1100°C for 30 minutes) as well as for three different holding times (10, 30, and 60 minutes at 1050°C). The interfacial microstructures were examined by scanning electron microscopy and the joining strengths were assessed by measuring shear strengths at room temperature. The results show that with increasing brazing temperature and holding time, joint microstructure changed obviously and shear strength was decreased. Shear strength varied from a maximum of 100±6 MPa to a minimum of 18±5 MPa, depending on the brazing conditions. These changes were attributed to an increase in the thickness of the oxide layer at the filler/metal alloy interface.