• 한국전산구조공학회논문집
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• 제30권4호
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• pp.283-288
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• 2017

스폿 용접 접합의 삼차원 모델링을 위하여 강한 불연속이 내장된 유한요소를 사용하였다. 스폿 용접의 기하학적 형상을 유한요소망 대신 요소에 내장된 불연속 면에서의 특수한 응집 법칙을 이용하여 표현하였다. 이를 통하여 기존의 적응적 유한요소망을 이용하는 접근법과 달리 스폿 용접의 국부적인 형상에 독립적인 유한요소망을 구성할 수 있다. 또한, 스폿 용접의 형상을 명시적으로 고려하여 모델링함으로써 기존의 점 구속조건을 이용하는 접근법과 달리 망 독립적인 해를 얻을 수 있다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1990년도 특별강연 및 춘계학술발표 개요집
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• pp.155-159
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• 1990

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2005년도 춘계학술발표대회 개요집
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• pp.135-137
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• 2005

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1992년도 특별강연 및 추계학술발표 개요집
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• pp.73-76
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• 1992

• 한국기계기술학회지
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• 제13권4호
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• pp.143-148
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• 2011

This study analyzes the resistance spot weldability of DP60 steels. To analyze the resistance spot weldability of DP60 steels, tensile strength test and macro-section test were conducted for the resistance spot welds. Acceptable welding conditions were determined as a function of the resistance spot welding process parameters such as electrode force, welding time, and welding current. The lower limit of the welding lobe was the minimum shear tension strength for 590MPa-grade steel while the upper limit was determined whether or not expulsion was detected.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2004년도 춘계 학술발표대회 개요집
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• pp.333-335
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• 2004

현재 저항 점 용접 공정에서 기존의 공기 가압 장치에서 서보모터를 이용한 서보 가압 장치로 변화가 진행되고 있다. 특히 마이크로 접합부의 경우 그 대상부가 미소ㆍ미세하기 때문에 접합부의 두께, 변형량, 접합후 전기 저항의 크기 둥이 크게 문제가 될 수 있다. (중략)

• 한국정밀공학회지
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• 제14권3호
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• pp.41-49
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• 1997

Laser spot welding offers a unique combination of high speed. precision and low heat distortion, compared with conventional resistance spot welding. This combinatin of advantages is especially attractive for the automotive industry. Until now automobile fabrication is widely used resistance spot welding, however, because of geometric and structural problem, spot welding is required many welding machine in that reason by substituting spot welding with laser welding, it save the equipment cost. In the present study we measured ultimate strength and observed bead cross section of laser welded specimen and compared with that of the resistance spot welding results in order to adapt laser welding in automobile industry. Also for strength esti- mation we calculated the residual stress of laser welded zone. All calculations are performed with the ABAQUS code on a workstation.

• 한국자동차공학회논문집
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• 제13권5호
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• pp.42-49
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• 2005

In general, multi-lap spot weld joints are frequently present in automobile. Most research, however, has been focused on the single-lap spot weld joints until now. In this paper, tensile-shear strength tests are performed to examine the weldability of 3-lap spot joint welded by using the high strength steel sheet and the zinc coated steel sheet. The indentation depth and nugget diameter are used to propose the optimum welding conditions. The weldability is affected by the welding current and welding time for 3-lap spot joint. Meanwhile the expulsions is round to decrease with the increase of electrode force. The optimum welding conditions are presented for 3-lap spot joints of high strength steel sheet and zinc coated steel sheet.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1499-1504
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• 2007

Spot-welding is widely used to construct passenger car bodies in automotive industry. Occasionally severe spot-weld distortions in sub-assembly make further spot-weld difficult. In this paper, distortions for various spot-weld conditions are measured using coordinate measuring machine. Then, based on finite element solution for unit translation or unit rotation of nugget edge, equivalent loads for spot-weld distortions are determined. They can be used to predict the spot-weld distortion using finite element method.

• Journal of Welding and Joining
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• 제15권2호
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• pp.89-99
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• 1997

Spot welding is one of the important welding processes for the construction of thin metal sheet. Because of low investment cost, alternating welding current is widely applied for power source. Direct current type could be, however, recommened for high quality weldment. In this study, the effect of welding current type on the weldability and the electrode life in spot welding of aluminium alloy were investigated. Various welding tests were done by using three phase direct and alternating welding current, respectively. In spite of high variation of welding force, weld quality and electrode life with alternating welding current were shown better results than those with direct current for 2mm thick alumininum alloy sheets. This was due to excessive erosion of the positive electrode in direct welding current compared with the negative one. On the contrary to 2mm sheets, the welding parameters of alternating current for 1mm sheets must be carefully selected.