• Proceedings of the KWS Conference
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• 2006.10a
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• pp.234-236
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• 2006

• Proceedings of the KWS Conference
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• 1997.10a
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• pp.224-228
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• 1997

• Proceedings of the KWS Conference
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• 2002.05a
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• pp.26-28
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• 2002

• Proceedings of the KWS Conference
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• 2003.11a
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• pp.162-164
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• 2003

Spot welding, a kind of electric resistance welding, has been used in many fields such as automobile, aircraft, and appliance industry. This paper is to investigate the relationship between tensile shear strength and indentation depth under various welding conditions. The tensile shear strength increases with increasing the welding current in the range of 6-l3kA. The optimum welding conditions were 200∼250kg welding force and 10∼15 cycles welding time at 9kA welding current for EZNCEN. The indentation depth for optimum welding condition was 0.6mm at 9kA welding curent and 200kg welding force, 0.17mm at 9kA welding current and 300kg welding force, 0.19mm at 9kA welding current and 10cycle, 0.17mm at 9kA welding current and 15cycle welding time, respectively.

• 한국기계연구소 소보
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• s.9
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• pp.115-131
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• 1982

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.227-228
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• 2007

• Journal of Welding and Joining
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• v.27 no.4
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• pp.49-53
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• 2009

For Al 6k21-T4 alloy, linear laser welding produced the lower shear-tensile strength than the base metal. This study improved the shear-tensile strength by using the weaving laser at the optimized welding condition, i.e., 2mm weaving width and 25Hz frequency. The large weaving width increased the weld width, therefore improving the joint strength. For the specimen of low strength, the porosity was distributed continuously along the intersection between the plates and fusion line. However, for the optimized welding condition, large oval-shaped porosities were located only in the advancing track of the concave part. Regardless of the welding condition, solidification cracking was initiated at the intersection and propagated through small porosities in the weld part. furthermore, the concave part had more significant porosity in the weld and HAZ, respectively than the convex part. The continuity of porosities played a key role to determine the strength. And, the weaving width was an important parameter to control the strength.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.4
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• pp.41-47
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• 2000

In this study, the purpose finds out the best welding conditions for bonding of electric wire by ultrasonic welding. The material was plastic-insulating low-voltage-cabels for automobiles. The experiment varied the values of welding time and welding pressure and fixed the values of amplitude and energy. With the facts, the best condition for ultrasonic welding to achieve bonding exactly is gained according to the size of the cross-sectional area of the cable, and the adhesive intensity is greatly influenced by the variables of welding time and welding pressure. Also when the welding time and welding time and welding pressure increase as the cross-sectional areas of the cable increase the welding result in gained exactly.

• Journal of Welding and Joining
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• v.3 no.1
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• pp.3-10
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• 1985

Lamellar tearing susceptibility and through-thickness tensile ductility have been investigated in $40kg/mm^2 and 50kg/mm^2$ class tensile strength steel plates in terms of cleanliness of non-metallic inclusion and welding condition. The plate which had 0.01% cleanliness of A-type inclusion (MnS) had 61% of the reduction of area in the through-thickness direction and did not show lamellar tearing. Lamellar tearing susceptibility decreased with increasing the preheat and interpass temperature. The plate which had 0.04% cleanliness of A-type inclusion did not show lamellar tearing under the condition of 75.deg. C of preheat and interpass temperature.

• Journal of Power System Engineering
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• v.21 no.5
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• pp.86-91
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• 2017

Friction Stir Welding (FSW) is useful technique to join aluminum alloy with energy efficient and environment friendly. In this paper, the design of experiment with three-way factorial design was adopted for optimum conditions of welding variables in the FSW of Al 6061 alloy. Tools of shoulder diameter of 9, 12, 15 mm and pin length of 1.5 mm were used. Also the material's dimension for welding were $2{\times}100{\times}150mm$, and the tensile specimens were worked by water-jet technique. Welding variables were shoulder diameter, rotating speed and travel speed of tool. From the results of this work, the welding factor influenced on yield strength most was travel speed and the optimum condition for FSW was predicted as the shoulder diameter of 15 mm, welding speed of 500 mm/min and rotating speed of 2,000 rpm. Also the presumption range of yield strength at optimal condition of reliability 99% was estimated to $207.19{\pm}9.91MPa$.