• 제목/요약/키워드: intermetallic

검색결과 782건 처리시간 0.03초

알루미늄 합금/고장력 강판 겹치기 마찰교반점용접에서 공구 형상과 삽입 깊이에 따른 접합 특성 (Effect of Tool Shape and Insertion Depth on Joining Properties in Friction Stir Spot Welding of Aluminum Alloy/high-strength Steel Sheets)

  • 안수호;정영근
    • 한국분말재료학회지
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    • 제31권1호
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    • pp.37-42
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    • 2024
  • Friction stir spot welding (FSSW) is a solid-state joining process and a rapidly growing dissimilar material welding technology for joining metallic alloys in the automotive industry. Welding tool shape and process conditions must be appropriately controlled to obtain high bonding characteristics. In this study, FSSW is performed on dissimilar materials AA5052-H32 aluminum alloy sheet and SPRC440 steel sheet, and the influence of the shape of joining tool and tool insertion depth during joining is investigated. A new intermetallic compound is produced at the aluminum and steel sheets joint. When the insertion depth of the tool is insufficient, the intermetallic compound between the two sheets did not form uniformly. As the insertion depth increased, the intermetallic compound layer become uniform and continuous. The joint specimen shows higher values of tensile shear load as the diameter and insertion depth of the tool increase. This shows that the uniform formation of the intermetallic compound strengthens the bonding force between the joining specimens and increases the tensile shear load.

Under Bump Metallurgy의 종류와 리플로우 시간에 따른 Sn 솔더 계면반응 (Interfacial Reactions of Sn Solder with Variations of Under-Bump-Metallurgy and Reflow Time)

  • 박선희;오태성
    • 마이크로전자및패키징학회지
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    • 제14권3호
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    • pp.43-49
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    • 2007
  • 웨이퍼 레벨 솔더범핑시 under bump metallurgy (UBM)의 종류와 리플로우 시간에 따른 Sn 솔더범프의 평균 금속간화합물 층의 두께와 UBM의 소모속도를 분석하였다. Cu UBM의 경우에는 리플로우 이전에 $0.6\;{\mu}m$ 두께의 금속간화합물 층이 형성되어 있었으며, $250^{\circ}C$에서 450초 동안 리플로우함에 따라 금속간화합물 층의 두께가 $4\;{\mu}m$으로 급격히 증가하였다. 이에 반해 Ni UBM에서는 리플로우 이전에 $0.2\;{\mu}m$ 두께의 금속간화합물 층이 형성되었으며, 450초 리플로우에 의해 금속간화합물의 두께가 $1.7\;{\mu}m$으로 증가하였다. Cu UBM의 소모속도는 15초 리플로우시에는 100 nm/sec, 450초 리플로우시에는 4.5 nm/sec이었으나, Ni UBM에서는 소모속도가 15초 리플로우시에는 28.7 nm/sec, 450초 리플로우시에는 1.82 nm/sec로 감소하였다.

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용융 Zn 합금에서 Fe합금의 PTA 오버레이 용접 금속간 상의 형성과 진행 (Formation and Progression of Intermetallic phase on Iron Base Alloy PTA weld overlay in Molten Zn Alloys)

  • ;백응률
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2009년 추계학술발표대회
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    • pp.95-95
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    • 2009
  • Zinc coatings provide the most effective and economical way of protecting steel against corrosion. There are three types of galvanizing lines typically used in production line in galvanizing industries,Galvanize (GI) coating (Zn-0.1-0.3%Al), Galfan coating (Zn-5%Al), Galvalume(GL) coating (45%Zn-Al). In continuous Galvanizing lines, the immersed bath hardware (e.g. bearings, sink, stabilizer, and corrector rolls, and also support roll arms and snout tip) are subjected to corrosion and wear failure. Understanding the reaction of these materials with the molten Zn alloy is becomes scientific and commercial interest. To investigate the reaction with molten Zn alloys, static immersion test performed for 4, 8, 16, and 24 Hr. Two different baths used for the static immersion, which are molten Zn and molten Zn-55%Al. Microstructures characterization of each of the materials and intermetallic layer formed in the reaction zone was performed using optical microscope, SEM and EDS. The thickness of the reaction layer is examined using image analysis to determine the kinetics of the reaction. The phase dominated by two distinct phase which are eutectic carbide and matrix. The morphology of the intermetallic phase formed by molten Zn is discrete phase showing high dissolution of the material, and the intermetallic phase formed by Zn-55wt%Al is continuous. Aluminum reacts readily with the materials compare to Zinc, forming iron aluminide intermetallic layer ($Fe_2Al_5$) at the interface and leaving zinc behind.

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알루미늄의 Sb 첨가에 따른 미세조직, 전기전도도 및 기계적 특성 변화 (Influence of Sb Addition on Microstructure, Mechanical Properties and Electric Conductivity of Aluminum)

  • 유효상;김용호;이병권;고은찬;이성희;이상찬;손현택
    • 한국재료학회지
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    • 제32권11호
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    • pp.489-495
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    • 2022
  • This research investigated how adding Sb (0.75, 1.0, 2.0 and 5.0 wt%) to as-extruded aluminum alloys affected their microstructure, mechanical properties, electric and thermal conductivity. The addition of Sb resulted in the formation of AlSb intermetallic compounds. It was observed that intermetallic compounds in the alloys were distributed homogenously in the Al matrix. As the content of Sb increased, the area fraction of intermetallic compounds increased. It can be clearly seen that the intermetallic compounds were crushed into fine particles and homogenously arrayed during the extrusion process. As the Sb content increased, the average grain size decreased remarkably from 282.6 ㎛ (0.75 wt%) to 109.2 ㎛ (5.0 wt%) due to dynamic recrystallization by the dispersed intermetallic compounds in the aluminum matrix during the hot extrusion. As the Sb content increased from 0.75 to 2.0 wt%, the electrical conductivity decreased from 61.0 to 59.8 % of the International Annealed Copper Standard. Also, as the Sb content increased from 0.75 to 2.0 wt%, the ultimate tensile strength did not significantly change, from 67.3 to 67.8 MPa.

고주파 유도가열을 통한 알루미늄 기판재위 Ni-Al계 금속간화합물의 연소합성코팅에 관한 연구 (A Study for Ni-Al based Intermetallics Coating onto Aluminum Substrate by Induction Heating)

  • 이한영
    • Tribology and Lubricants
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    • 제28권2호
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    • pp.56-61
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    • 2012
  • In order to investigate the possibility of Ni-Al based intermetallics coating onto aluminum substrate, the coating process for induction heating has been evaluated by microscopically analyzing the intermetallic layers coated at temperatures lower than the melting temperature of aluminum. The coating layers were divided into two parts with different microstructure along the depth. Hard $NiAl_3$ layer was found at lower parts of the coatings near the interface with aluminum substrate. This layer was formed by the diffusion of aluminum atoms from the substrate into the coating layer across the interface during the induction heating. Meanwhile, at the upper parts of the coating near the surface, a large amount of un-reacted Ni was still remained and surrounded by several Ni-Al based intermetallic compounds, such as $Ni_3Al$, NiAl and $Ni_2Al_3$ formed by the lattice diffusion.

Al6Si2Cu 알루미늄 합금의 기계적 물성 향상을 위한 이단계 고용화 열처리 (Two-step Solution Treatment for Enhancement of Mechanical Properties of AlSiCu Aluminum Alloy)

  • 박상규;김정석
    • 열처리공학회지
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    • 제31권3호
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    • pp.97-103
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    • 2018
  • The objective of this study is to develop the mechanical properties of AlSiCu aluminum alloy by the two-step solution heat treatment. The microstructure of gravity casting specimen represents a typical dendrite structure having a secondary dendrite arm spacing (SDAS) of 40 mm. In addition to the Al matrix, a large amount of coarsen eutectic Si phase, $Al_2Cu$ intermetallic phase, and Fe-rich phases are generated. The eutectic Si phases are fragmented and globularized with solution heat treatment. Also, the $Al_2Cu$ intermetallic phase is resolutionized into the Al matrix. The $2^{nd}$ solution temperature at $525^{\circ}C$ might be a optimum condition for enhancement of mechanical properties of AlSiCu aluminum alloy.

TiAl 금속간 화합물의 미세조직에 따른 고온변형특성 (High Temperature Deformation Behavior of Ti-Al Intermetallic Compound - Microstructure Effect)

  • 하태권;정재영;이광석;장영원
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2003년도 춘계학술대회논문집
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    • pp.295-298
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    • 2003
  • High temperature deformation behavior of a Ti-Al intermetallic compound has been investigated. Specimens with a near gamma and a lamella structures were obtained by performing heat treatment at 1200 and 1330$^{\circ}C$, respectively, for 24 hr and stabilized at 900$^{\circ}C$ for 4 hr followed by air cooling. A series of load relaxation tests has been conducted on these samples at temperatures ranging from 850 to 950$^{\circ}C$ to construct flow curves in the strain rate range from 10$\^$-6//s to 10$\^$-3//s. Strain hardening was observed even at the temperature of 950$^{\circ}C$ in both the near gamma and the lamella structures. Further aging treatment for 12 hr at test temperatures has found to cause no softening in both microstructures.

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Al-Ni계의 기계·화학적 방법으로 제조된 Raney Ni의 미세 구조 분석 (Microstructure of Raney Ni fabricated by Mechanochemical Process in Al-Ni System)

  • 최재웅;이창래;강성군
    • 한국재료학회지
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    • 제13권1호
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    • pp.24-30
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    • 2003
  • The Raney Ni catalyst was fabricated by mechanochemically process(MC process) in the Al-Ni system. Intermetallic compound obtained by mechanical alloying was leached in an alkaline solution. The characteristics of the mechanically alloyed powder and Raney Ni catalyst were analyzed by XRD, ICP-AES and EXAFS. In Al-50wt.%Ni, the metastable intermetallic compound phase close to AlNi phase was obtained by mechanical alloying unlike Al-Ni equilibrium phase diagram. The metastable intermetallic compound was transformed into $Al_3$$Ni_2$phase via the annealing at $750^{\circ}C$. The microstructure of Raney Ni fabricated by MC process was mainly bcc Ni including fcc Ni.

입자강화 금속기 복합재료의 고온 피로강도 향상에 관한 연구 (A Study on the Improvement of Fatigue Strength in Particulate Reinforced Metal Matrix Composites at Elevated Temperatures)

  • 신형섭
    • 대한기계학회논문집A
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    • 제24권5호
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    • pp.1146-1154
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    • 2000
  • Fatigue strength of NiAl and Ni$_3$Al particulate reinforced aluminum alloy composites fabricated by the diecasting method was examined at room and elevated temperatures. The results were compared wit h that of SiC particulate reinforced one. The particulate reinforced composites showed some improvement in the static and fatigue strength at elevated temperatures when compared with that of Al alloy. The composites reinforced by intermetallic compound particles showed good fatigue strengths at elevated temperatures especially $Ni_3AI_{p}/Al$ alloy composite showed good fatigue limit up to high temperature of 30$0^{\circ}C$. Adopting intermetallic compound particle as a reinforcement phase, it will be possible to develop MMC representing better fatigue property at elevated temperature.

규칙화된 Fe-Al 계 금속간 화합물의 산화특성과 미끄럼 마모거동과의 관계에 대한 연구 (A Study on the Relationship between Oxidation and Sliding Wear Behavior of Ordered Fe-Al Intermetallic Alloys)

  • 김용석
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1999년도 춘계학술대회논문집
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    • pp.144-148
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    • 1999
  • The relationship between oxidation and sliding wear behavior of Fe-28 at%. Al alloys with B2 ordered structure has been investigated. Sliding wear tests of the alloys have been carried out under various environmental conditions using a pin-on-disk wear tester. The wear rate of the ordered alloys in an oxygen atmoshpere was found to be much lower than in an oxygen atmosphere showed that Fe2O oxides formed on the wearing surface. The oxide layer prevented direct contact of the two mating materials and therefore improved wear resistance of the Fe-Al intermetallic alloy. It was found that the surface Al2O3 oxide layer which provides good oxidation resistance and improved mechanical properties broke down easily and didnot function properly as an oxidation barrier.

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