• 제목/요약/키워드: Welding speed

검색결과 813건 처리시간 0.026초

고전류 $CO_2$용접에서의 금속이행 및 스패터 발생 현상에 관한 연구 (A Study on the Metal Transfer and Spatter Generation in High Current $CO_2$ Welding)

  • 김남훈;유회수;김희진;고진현
    • Journal of Welding and Joining
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    • 제21권3호
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    • pp.51-57
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    • 2003
  • The metal transfer in $CO_2$ welding shows the transition of transfer mode from short-circuiting to repelled transfer will the increase of welding current. While the short-circuiting mode in $CO_2$ welding has been studied very extensively relating with droplet formation and spatter generation, the repelled transfer has little been understood. In this study, high current $CO_2$ welding has been performed with bead-on-plate welds along with the waveform analyzer and high speed camera. The image of high speed camera was synchronized with its waveform so that the moment of spatter generation could be realized during drop detachment. As a results of this study, it was found that welding arc changes its location either once or three times and thus single or double pulse signals were developed in the voltage waveform. Whenever the arc moved its location, new arc was developed in a explosive way and thus it caused spatter generation. Specially severe spattering took place when the waveform showed a double-peak pattern. As a consequence of these results, new waveform control techniques could be suggested for suppressing the spatter generation in the high-current $CO_2$ welding.

화상처리에 의한 Gas Tungsten Arc 용접에서의 용융지폭제어에 관한 연구 (A Study of Weld Pool width Control in Gas Tungsten Arc Welding Using the Digital Image Processing)

  • 김동철;이세헌;엄기원
    • 대한기계학회논문집A
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    • 제20권9호
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    • pp.2760-2769
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    • 1996
  • The feedback control systems of welding process using visual information can improve weld qualities. However, it is very difficult to get the visual information of weld pool since the light intensity of welding arc is much stronger than that of the weld pool. To explore the possibility of extending the capability of automatic welding machines, a study of a closed loop controlled welding system consisted of a GTA welding machine, a vision system, a stepping motor system and a digital computer was undertaken. Particularly, in this system, a CCD camera with a long wavelength pass filter was used to get a better weld pool image. Subsequently, an image analysis technique has been developed to measure the weld pool width. Using this weld pool width measurement, a colsed loop control system adjusted welding speed to maintain a constant weld pool width.

The Effects of GMAW Parameters on Penetration, Hardness and Microstructure of AS3678-A350 High Strength Steel

  • Kaewsakul, Nut;Putrontaraj, Rungsuk;Kimapong, Kittipong
    • International Journal of Advanced Culture Technology
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    • 제3권1호
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    • pp.169-178
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    • 2015
  • This research aims to study the effects of various welding parameters in gas metal arc welding (GMAW) process on welding penetration, microstructure and hardness of AS3578-A350 high strength steel with the thickness of 10 mm. The welding process parameters were a welding current of 100-200A, an arc voltage of 20-30V, a welding speed of 20-60 cm/min and a gas shielding type of Ar and $Ar+CO_2$. The summarized experimental results are as follows. An increase of the welding current and voltage affected to increase the penetration depth of the joint. However, when the welding speed was decreased, it increased the penetration depth of the joint. Using the Ar gas for shielding the weld area, produced the higher penetration depth and the less narrow weld bead than the joint that was shielded by the mix gas of $Ar+CO_2$. The variation of the welding process parameters affected to produce the various microstructures of weld metal and heat affected zone and also showed the various kind of hardness along the weld joint.

구리와 알루미늄 이종금속 판재간의 전기저항가열 표면마찰 스폿용접 특성 (Characteristics of Electric Resistance Heated Surface Friction Spot Welding Process of Copper and Aluminum Dissimilar Metal Sheets)

  • 순샤오광;진인태
    • 한국기계가공학회지
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    • 제21권8호
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    • pp.99-109
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    • 2022
  • In this study, an electric resistance-heated surface friction spot-welding process was proposed and tested for the spot-welding ability of copper and aluminum dissimilar metal sheets using electric resistance heating and surface friction heating. This process has welding variables, such as the current value, energizing cycles, rotational speed, and friction time. The current value and energizing cycle can affect the resistance heat, and the rotational speed of the rotating pin and friction time influence frictional heat generation. Resistance heating before friction heating has a preheating effect on the Cu-Al contact interface and a positive effect on preventing friction heat loss during the friction stage. However, because resistance preheating can soften the copper sheet and affect the contact stress and friction coefficient, it has difficulties that may adversely affect frictional heat generation. Therefore, the optimal combination of welding variables should be determined through simulations and experiments of the spot-welding process to determine the effects of electric resistance preheating on the suggested process. Through this procedure, it is known that the proposed spot-welding process can improve the welding quality during the spot welding of Cu-Al sheets.

싱글모드 파이버 레이저를 이용한 SUS304와 Cu의 고속 겹치기 용접에서 접합부 및 인장시험 파단부의 특성에 관한 연구 (A Study on the Characteristic of Weld Joint and Tensile Fracture of SUS304 and Cu High-Speed Dissimilar Lap Welds by Single Mode Fiber Laser)

  • 이수진;김종도;카타야마 세이지
    • Journal of Welding and Joining
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    • 제32권6호
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    • pp.56-63
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    • 2014
  • To develop and understand dissimilar metals joining of Stainless steel and Copper, ultra-high speed laser lap welding was studied using single mode fiber laser in this study. SUS304 and Cu have large differences in materials properties, and Cu and Fe have no intermetallic compounds by typical binary phase of Cu and Fe system. In this study, ultra-high speed lap welds of SUS304 and Cu dissimilar metals using single-mode fiber laser was generated, and weldability of the weld fusion zone was evaluated using a tensile shear test. To understand the phenomenon of tensile shear load, weld fusion zone of interface weld area and fracture parts after tensile shear test were observed using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) analysis system. And it was confirmed that Cu was easily melting and penetrating in the grain boundaries of SUS304 because of low melting temperature. And high thermal conductivity of copper occurred dissipate heat energy rapidly. These properties cause the solidification cracking in weld zone.

고강도 Al합금 A5083 및 A7N01의 $CO_2$ 레이저 용접성 ($CO_2$ Laser Weldablity of High Strength Al Alloy A5038 and A7N01)

  • 김장량;하용수;강정윤;김인배
    • 한국레이저가공학회지
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    • 제4권2호
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    • pp.1-12
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    • 2001
  • This study has been performed to evaluate basic characteristics of CW-CO$_2$ laser welding process of A5083 and A7N01 Al alloy. The effect of welding parameters, such as shielding gas, gas flow rate, laser power and welding speed on the bead shape and porosity from bead on plate welding tests have been investigated. Welds shielded by He gas had deeper penetration and better bead shape than those shielded by Ar. The penetration depth was augmented with the increase of laser Power and the decrease of welding speed. Welds of A7N01 alloy had deeper penetration than those of A5083 alloy In beads of A5083 alloy which has deeper penetration, the volume fraction of porosities was high due to the number of its was few, but size of its was larger. The case of deeper penetration beads of A7N01 alloy, the porosity reduced under relatively higher power The Volume fraction of porosities in weld of A5083 alloy was significantly higher than that in weld of A7N01 alloy.

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Friction Stir Spot Welding of AA5052 Aluminum Alloy and C11000 Copper Lap Joint

  • Prasomthong, Suriya;Sangsiri, Pradit;Kimapong, Kittipong
    • International Journal of Advanced Culture Technology
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    • 제3권1호
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    • pp.145-152
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    • 2015
  • The article aims to apply a friction stir spot welding for producing the lap joint between AA5052 aluminum alloy and C11000 copper alloy. The dimension of the materials was 100 mm in length, 30 mm in width and 1.0 mm in thickness. The copper plate was set overlap the aluminum plate by 30 mm. The welding parameter was the rotating speed of 2500-4000 rpm, the pin inserting rate of 2-8 mm/min and the holding time of 6 sec. The mechanical properties test and the microstructure investigation were performed to evaluate the lap joint quality. The summarized results are as follows. The friction stir spot welding could produce effectively the lap joint between AA5052 and C11000 copper. Increase of the rotating speed and holding time directly affected to decrease the tensile shear strength of the lap joint. The optimized welding parameters in this study that indicated the tensile shear strength of 864 N was the rotating speed of 3500 rpm, the pin inserting rate of 6 mm/min and the holding time of 4sec. The experimental results also showed that the hardness of the weld metal was lower than that of the base materials.

A16061-T6 마찰교반용접시 핀 형상과 이송속도가 기계적 강도에 미치는 영향에 관한 연구 (A Study on the Effect that Pin Shape and Welding Speed have an Influence on Mechanical Strength in Friction Stir Welding A16061-T6)

  • 박희상;이영호;최원두;고준빈
    • 한국공작기계학회논문집
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    • 제17권4호
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    • pp.22-28
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    • 2008
  • Friction stir welding(FSW) is an relatively new solid state joining process. A1606l-T6 aluminium alloy has gathered wide acceptance in the fabrication of light weight structures requiring a high strength to weight ratio and good corrosion resistance. This friction stir process(FSP) uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, etc., and tool pin profile playa major role in deciding FSP zone formation in A16061-T6 aluminium alloy. Tow different tool pin profiles have been used to fabricate the joints. The formation of friction stir processed zone has been analysed macroscopically. Tensile properties of the joints have been evaluated and correlated with the friction stir processed zone formation.

철도차량 적용을 위한 Al alloy(A6005)-Mg alloy(AZ61) 이종소재 마찰교반용접 특성 연구 (Characteristics of Dissimilar Materials Al alloy(A6005)-Mg alloy(AZ61) Under Friction Stir Welding for Railway Vehicle)

  • 이우근;김정석;선승주;임재용
    • 한국산학기술학회논문지
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    • 제17권8호
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    • pp.706-713
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    • 2016
  • 본 연구에서는 이종소재 A6005-AZ61 접합을 위하여 마찰교반용접의 툴 삽입 위치와 모재의 냉각 유 무에 따라 용접부 특성을 분석하였다. 다른 용접 조건들인 툴 회전속도와 이송속도는 500rpm-30mm/min으로 고정하고 Advancing side에 알루미늄 합금(A6005), Retreating side에 마그네슘 합금(AZ61)을 배치하여 용접을 진행하였다. 용접은 여섯 가지 케이스를 진행하였다. 용접부 특성을 관찰하기 위하여 인장 시험을 진행하고, 광학현미경을 사용하여 용접부의 미세조직을 관찰하였다. 인장시험 결과 마그네슘 합금 방향으로 툴을 1mm 이동시키고 모재에 냉각을 시킨 조건에서 강도가 가장 높게 나타났다. 동일한 용접 조건에서 냉각을 한 경우에 냉각을 하지 않은 것 보다 강도가 약 2배 높게 측정되었다. 툴의 위치는 용접부 중심에서 알루미늄 합금 방향으로 1.7mm, 마그네슘 합금 방향으로 1.7mm 이동시켜 과도한 편심을 적용한 용접 조건에서는 교반이 잘 이루어지지 않아 용접부의 건전성이 가장 좋지 않았다. 과도한 편심을 적용한 용접 조건에서는 교반이 잘 이루어지지 않아 용접부의 건전성이 가장 좋지 않았다. 본 연구를 통해 A6005-AZ61 이종 마찰교반용접시 용접속도와 툴 회전속도만큼 모재의 온도 조절과 툴 삽입위치가 중요한 용접변수임을 확인 하였다.

승합차의 램프 디자인과 제작을 위한 이종재료의 접합 (A Study on Welding of Dissimilar Materials for Van-Ramp Design and Production)

  • 이정현;김인철
    • 한국생산제조학회지
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    • 제20권4호
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    • pp.434-439
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    • 2011
  • There are about 2.4million disabled in Korea, 2009. Also, Korean society entered into an aging society. Therefore disable and elderly are getting more involved in our society. This study proposes simple ramp design for wheel chair users and welding method and condition for manufacturing. In the middle of ramp, screw jack and motor are installed so that ramp can be moved left and right side. To make the ramp moves easily, ramp was fixed by installing LM guide on both sides. Ramp production for using Nd:YAG laser certain dissimilar welding in stainless steel sheet and cold reduced carbon steel. The output was fixed by 3kW, the speed was increased to 2~7m/min, Argon was used as shielding gas and the flow rate was changed to 10~30L/min. The proper welding condition is the output 3kW and welding speed 2~5m/min.