• 제목/요약/키워드: Dissimilar material

검색결과 216건 처리시간 0.026초

A study on Stress Singularities for V-notched Cracks in Anisotropic and/or Pseudo-isotropic Dissimilar Materials

  • Cho, Sang-Bong;Kim, Jin-kwang
    • International Journal of Precision Engineering and Manufacturing
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    • 제3권2호
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    • pp.22-32
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    • 2002
  • V-notched crack problems can be formulated as eigenvalue problems. The problem ova v-notched crack in anisotropic and/or pseudo-isotropic dissimilar materials was formulated as an eigenvalue problem to discuss stress singularities. The eigenvalue problem was served by the commercial numerical program; MATHEMATICA. The specific data of eigenvalues possessing the stress singularity were obtained. Stress singularities fur v-notched cracks in anisotropic and/or pseudo-isotropic dissimilar materials were discussed according to the relation between wedge angle and material property. It was shown that there are three cases of eigenvalues possessing the stress singularity; one real, two real and one complex.

연속파형 Nd:YAG레이저를 이용한 Inconel 600와 STS 304의 이종금속용접 (Dissimilar Metal Welding of Inconel 600 and STS304 by a continuous wave Nd:YAG Laser)

  • 신호준;유영태;송성욱
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.1120-1125
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    • 2004
  • Welding characteristics of STS304 stainless steel and Inconel 600 using a continuous wave Nd:YAG laser are experimentally investigated. Alloy 600 being used in steam generator tubing of pressurized water reactor(PWR) exposed to some corrosion environment, stress corrosion cracking can occur on this material. Presented here are the results from a series of experiments in which dissimilar metal welds were made using the gas tungsten arc welding process with pure argon shielding gas. But It is well known that solidification cracking susceptibility of austenitic alloys depends on the solidification temperature range and amount/distribution of solute rich liquid that exists at the terminal stages of solidification. An experimental study was conducted to determine effects of welding parameters and to optimize those parameters that have the most influence on eliminating or reducing the extent welding zone formation at dissimilar metal welds.

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톱니형상면의 압축에 의한 성장거동 시뮬레이션 (Simulation of Growth Behavior of Sawtoothed Interface by the compression)

  • 정태훈
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2002년도 추계학술대회 논문집
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    • pp.90-94
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    • 2002
  • In this paper, Compression in the case where dissimilar blocks are twinned variously are carried out in the condition of lubricated interface. The degree of growth is experimentally investigated. Moreover, numerical simulations are carried out by the elastic-plastic FEM for the case of the dissimilar blocks with the initial sawtooth angle of 60。. The dissimilar blocks are twinned, larger difference between material properties leads smaller growth, and the degreased interface leads smaller growth than that in the lubricated one. Furthermore, by the simulation of compression where dissimilar blocks are twinned, it is confirmed that the tendency of the general deformation pattern is very similar to the experiment.

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CW Nd:YAG 레이제에 의한 이종금속 용접특성 (Welding Characteristics of Dissimilar Metal by Continuous Wave Nd:YAG Laser)

  • 유영태;신호준;송성욱
    • 한국정밀공학회지
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    • 제21권11호
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    • pp.53-60
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    • 2004
  • Laser welding techniques have been characterised for various materials. In this paper, the laser weldability of STS304 stainless steel and Inconel 600 at dissimilar metal welds using a continuous wave Nd:YAG laser are experimentally investigated. Inconel 600 is being used in a steam generator tubing of pressurized water reactor(PWR) exposed to some corrosion. Stress corrosion cracking can occur on this material. An experimental study was conducted to determine effects of welding parameters, on eliminating or reducing the extent welding zone formation at dissimilar metal welds and to optimize those parameters that have the most influence parameters such as focus length, power, beam speed, shielding gas, and wave length of laser were tested.

A5J32/A5052 이종 알루미늄 합금 겹치기 마찰교반접합부의 인장성질에 미치는 재료배열 및 접합조건의 영향 (Effects of Welding Conditions and Material Arrangement on Tensile Properties of Friction Stir Lap Welded of Dissimilar Al Alloy, A5J32/A5052)

  • 윤태진;강명창;강정윤
    • 한국분말재료학회지
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    • 제20권4호
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    • pp.302-307
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    • 2013
  • A5J32-T4 and A5052-H32 dissimilar aluminum alloy plates with thickness of 1.6 and 1.5 mm were welded by friction stir lap welding (FSLW). The FSLW were studied using different probe length tool and various welding conditions which is rotation speed of 1000, 1500 rpm and welding speed of 100 to 600 mm/min and material arrangement, respectively. The effects of plunge depth of tool and welding conditions on tensile properties and weld nugget formation. The results showed that three type nugget shapes such as hooking, void, sound have been observed with revolutionary pitch. This plunge depth and material arrangement were found to effect on the void and hooking formation, which in turn significantly influenced the mechanical properties. The maximum joint efficiency of the FSLWed plates was about 90% compared to base metal, A5052-H32 when the A5052-H32 was positioned upper plate and plunge depth was positioned at near interface between upper and lower plates.

열박음을 고려한 이종재 금형의 피로수명 예측에 관한 연구 (A Study on the Prediction of Fatigue Life in Dissimilar Materials Die Considering the Heat Shrink Fit)

  • 여은구;김엽래
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1999년도 춘계학술대회 논문집
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    • pp.93-98
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    • 1999
  • Generally, the - life of die is limited by fatigue fracture or dimensional inaccuracy originated from wear. In this paper, to predict the fatigue life of the dissimilar materials die, the stress and stxain histories of die can be predicted by the analysis of elasto-plastic finite element neth hod and the elastic analysis of die during the process analysis of workpiece. Using heat shrink fit analysis, initial stress of the k r t die is computed. Also, the stress-life curve of die material can be obtained through experiment. With the above two facts, we propose the analysis method of predicting fatigue life in die. In the proposed model, tlz analysis of elastic-plastic finite element method for material is carried out by using ABAQUS. Surface force resulted from the contacting border of the die and workpiece is tmnsformed into the nodal force of die to implement elastic analysis. Besides, the proposed analysis model of die is applied to the one material and the dissimilar materials extrusion die.

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60 kHz 초음파 공구 혼을 이용한 이종재료접합의 공정조건 최적화 (The optimization of processing condition of dissimilar material bonding using the 60 kHz ultrasonic transducer)

  • 이동욱;전의식
    • 한국산학기술학회논문지
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    • 제14권3호
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    • pp.991-996
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    • 2013
  • 본 논문에서는 유리와 구리의 이종재료 접합을 위해 고유진동수를 60 [kHz]로 갖는 초음파 혼을 설계하고자 하였다. 초음파 혼의 입력단과 출력단의 단면비, 혼의 길이 등 관계식을 통해 설정하였으며 설계된 혼의 타당성 분석을 위해 모달해석을 수행하였다. 기초실험을 통하여 공정변수 및 반응변수를 설정하였으며, 초음파 공구 혼을 이용하여 이종재료 접합 강도 실험을 실시하였다. 또한 실험 결과를 통해 최적 공정조건을 도출하였다.

이종 알루미늄 합금의 로봇 미그 용접 시 용접재료에 따른 기계적 및 전기화학적 특성 평가 (Mechanical and electrochemical characteristics with welding materials in robotic MIG welding of dissimilar Al alloys)

  • 김성종;한민수;우용빈
    • Corrosion Science and Technology
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    • 제12권5호
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    • pp.245-252
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    • 2013
  • In this study, mechanical and electrochemical characteristics with welding material in MIG welded with ROBOT for dissimilar Al alloys were investigated using various experiment methods. The MIG welding by ROBOT with ER5183 and ER5556 for the 5456-H116 and 6061-T6 Al alloy were carried out. The hardness of welding zone was lower than that of base metal. In electrochemical experiment, ER5183 welding material presented excellent characteristics. The yield strength and maximum tensile strength in welding with welding material of ER5183 presented lower value than those of ER5556. The elongation and time-to-fracture showed the opposite results.

Tensile and impact toughness properties of various regions of dissimilar joints of nuclear grade steels

  • Karthick, K.;Malarvizhi, S.;Balasubramanian, V.;Krishnan, S.A.;Sasikala, G.;Albert, Shaju K.
    • Nuclear Engineering and Technology
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    • 제50권1호
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    • pp.116-125
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    • 2018
  • Modified 9Cr-1Mo ferritic steel is a preferred material for steam generators in nuclear power plants for their creep strength and good corrosion resistance. Austenitic stainless steels, such as type 316LN, are used in the high temperature segments such as reactor pressure vessels and primary piping systems. So, the dissimilar joints between these materials are inevitable. In this investigation, dissimilar joints were fabricated by the Shielded Metal Arc Welding (SMAW) process with Inconel 82/182 filler metals. The notch tensile properties and Charpy V-notch impact toughness properties of various regions of dissimilar metal weld joints (DMWJs) were evaluated as per the standards. The microhardness distribution across the DMWJs was recorded. Microstructural features of different regions were characterized by optical and scanning electron microscopy. Inhomogeneous notch tensile properties were observed across the DMWJs. Impact toughness values of various regions of the DMWJs were slightly higher than the prescribed value. Formation of a carbon-enriched hard zone at the interface between the ferritic steel and the buttering material enhanced the notch tensile properties of the heat-affected-zone (HAZ) of P91. The complex microstructure developed at the interfaces of the DMWJs was the reason for inhomogeneous mechanical properties.

기계가공이 이종용접부의 잔류응력에 미치는 영향에 관한 연구 (A Study on Machining Effects on Residual Stress at Dissimilar Metal Weld Region)

  • 이경수;이정근;이성호;박치용;이승건;박재학
    • Journal of Welding and Joining
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    • 제29권2호
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    • pp.56-63
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    • 2011
  • his paper aimed to understand the residual stress in the dissimilar metal welds of nuclear power plant. Two kinds of residual stress were considered, which caused by welding and machining. Residual stress due to mechanical machining was measured by hole-drilling technique and x-ray diffraction method for the SA508 and F316L. Weld residual stress at dissimilar metal weld between SA508 and F316L was evaluated by FEA. Residual stress profiles were obtained for the inside surface and through thickness of welds. Machining effect was also analyzed by FEA. According to the residual stress measurement, it was observed that mechanical machining can generate tensile stress on the surface of the test material. However, FEA results showed that mechanical machining did not increase the tensile stress on the surface of weld region. Further study with more elaborate measurement and numerical analysis is required to identify the effect of machining on residual stress in the dissimilar metal weld region.