• 제목/요약/키워드: High Strength Aluminum Tubes

검색결과 7건 처리시간 0.023초

알루미늄 관재의 액압성형성에 미치는 열처리의 영향 (Effect of Heat Treatments on the Hydroformability of Aluminum Tubes)

  • 이문용;강창룡
    • 열처리공학회지
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    • 제17권3호
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    • pp.146-150
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    • 2004
  • Because of the social needs for energy saving and the rigid environmental regulation, the development of light materials and new economical manufacturing technologies have been actively investigated. Recently, the hydroforming of high strength aluminum tube has attracted great interest due to its good strength-to-weight ratio, which could play an important role in lightweighting of automobile. However, the limited formability of high strength aluminum alloys is considered to hinder the active application of the hydroforming process. In this paper, the hydroformability of aluminum tubes with different heat treatments was investigated as the basic research of the hydroforming process for the high strength aluminum tubes.

열처리형 Al 압출재를 이용한 하이드로포밍 부품개발 (Development of Hydroformed Automotive Parts with Heat-treatable Aluminum Extrudates)

  • 이문용;강창룡;류성지
    • 열처리공학회지
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    • 제17권3호
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    • pp.165-172
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    • 2004
  • Compared with the hydroforming technology for steel, the hydroforming technology for aluminum has not been actively investigated. Recently, the hydroforming of high strength aluminum tubes has attracted great interest because of its good strength to weight ratio. In this study, front side member (FSM) is fabricated with the hydroforming of aluminum tube and the mechanical properties and dimensional accuracy of the hydroformed FSM is investigated. For hydroforming process, extruded aluminum tubes with ribs to improve the structural rigidity are used. To ensure the mechanical properties, the aluminum tubes are T6 heat-treated before hydroforming.

고강도 알루미늄 튜브의 온간 하이드로포밍 특성 (Warm Hydroforming Characteristics of High Strength Aluminum Tubes)

  • 이문용;강창룡;이상용
    • 소성∙가공
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    • 제13권5호
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    • pp.403-408
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    • 2004
  • Hydroformability of 6061 and 7075 aluminum tube materials was studied by warm hydroforming experiments. A special tooling and heating system was designed and manufactured in order to perform warm hydroforming between room temperature and $300^{\circ}C$. The control of tube temperature for warm hydroforming was made by the control of temperature of oil medium. Warm hydroformability was analyzed by tube appearances, tube elongation and hardness values. Hydroforming characteristics of 6061 and 7075 tubes showed different temperature dependence between room temperature and $300^{\circ}C$. The difference in hydroformabilities of 6061 and 7075 at elevated temperatures was interpreted by the different sensitivity to dynamic strain aging of both aluminum materials.

알루미늄 튜브를 이용한 자동차 리어 서브 프레임의 열간가스 성형해석 (Hot Air Forming Analysis of Automotive Rear Sub Frame using Aluminum Tube)

  • 김헌영;윤석진;이기동;김양수
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2008년도 추계학술대회 논문집
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    • pp.26-29
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    • 2008
  • Recently, the hydroforming of high strength aluminum tubes has many studies and applications in manufacturing industry, especially in automotive industry. But high strength aluminum tube has limited expansion capability at most 15% at normal temperature. New manufacturing process, called hot air forming, is introduced to apply aluminum tube to the automotive sub frame components which have complex shape and require high expansion ratio about 40%. The process is carried out at the elevated temperature above $500^{\circ}C$, so numerous material properties and process parameters related to high temperature should be investigated and determined to get a sound product. In this paper, the hot air forming process of automotive sub frame was investigated. The effect of the forming parameters such as the temperature of tool, axial feeding and gas pressure are analyzes by using explicit finite element method.

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고주파유도용접된 열교환기용 BAS121합금튜브의 기계적 특성에 미치는 인발조건의 영향 (Effects of Drawing Parameters on Mechanical Properties of BAS121 Alloy Tubes for Heat-exchangers by High Frequency Induction Welding)

  • 한상우;김병일;이현우;전우용;국진선
    • 한국재료학회지
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    • 제14권12호
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    • pp.851-856
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    • 2004
  • The aim of this study is to investigate the optimum drawing parameter for BAS121 welded tubes. The BAS121 aluminium alloy tubes with 25 mm in external diameter and 1.3 mm in thickness for heat-exchangers were manufactured by high frequency induction welding with the V shaped convergence angle $6.5^{\circ}$ and power input 55 kW. With increasing the reduction of area ($13,\;21\%$) by drawing, tensile strength was increased and elongation was decreased. With increasing the reduction of area by drawing, hardness in weld metal increased rapidly, while that of base metal increased slowly. In the specimen with the outer diameter smaller than 22 mm, hardness of weld metal was higher than that of base metal. The optimum drawing parameter of area reduction in BAS121 alloys was estimated about $13\%$ because of the work hardening of welds.

알루미늄 튜브를 이용한 액압성형품 특성연구 (A Study on the Characteristics of Aluminum Tube Hydroformed Products)

  • 이혜경;이건엽;이성문;이영선;문영훈
    • 대한기계학회논문집A
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    • 제32권11호
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    • pp.1010-1015
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    • 2008
  • In this study, the characteristics of aluminum tube hydroformed products at different extrusion type and heat treatment conditions were investigated. For the investigation, as-extruded, full annealed and T6-treated Al 6061 tubes at different extrusion type were prepared. To evaluate the hydroformability, free bulge test was performed at room temperature to $300^{\circ}C$. Also mechanical properties of hydroformed products at various pre- and post-heat treatments were estimated by hexagonal prototype hydroforming test at $250^{\circ}C$. And the tensile test specimens were obtained from hexagonal prototype hydroformed tube. As a results, hydroformability of full annealed tube is $5{\sim}8%$ higher than that of extruded and T6-treated tube. The tensile strength and elongation of T6-post heat treated indirect extrusion tube were more than 330MPa and 12%, respectively. However, T6 pre treated hydroformed product represents high strength, 330MPa and low elongation, 8%. Therefore, Hydroformability of Al6061 tube showed similar value for both extrusion types. However flow stress of direct tube showed $20{\sim}50MPa$ lower value than indirect tube.

금속과 고분자 재료의 접합강도 해석 (Analysis of Joining Strength in Electromagnetic Joining of Metals to High Toughness Polymers)

  • 손희식;김남환;이종수
    • 한국정밀공학회지
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    • 제9권3호
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    • pp.110-116
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    • 1992
  • Electromgnetic joining of aluminum alloy tubes to high toughness polyurethane rubber cores is studied in order to estimate the joining strength and to analyze the effect of the process variables. The equation which can estimate the joining strength is proposed under considering the elastic recovery of the polyurethane core and the radial shrinkage of the core by pulling it axially. The obtained results are as follows : 1) The joining strength is mainly dependent on the magnitude of residual elastic strain of the polyurethane core. 2) The radial shrinkage (residual strain reduction) of the core during the axial pulling causes the joining strength to decrease severely. The equation for the reduced axial strength is proposed and it is found that the estimated values agree well with experimental results. 3) The magnitude of radial shrinkage could be reduced for the smaller value of ratio l/r. 4) The joining strength in metal/polymer joining increases as the friction coefficient increases. But its effect of friction coefficient is insignificant in comparison with the case of metal/metal joining.

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