Journal of Welding and Joining
- Volume 18 Issue 2
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- Pages.64-68
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- 2000
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- 2466-2232(pISSN)
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- 2466-2100(eISSN)
$CO_2$ Weldability of Zn Coated Steel Sheet(2) -Mechanism of Weld Defect Formation-
아연도금강판의 $CO_2$ 용접특성(2) - 용접결함의 형성기구 -
Abstract
The mechanism of the blowhole and the pit formation in lap-jointed fillet Co₂arc welds of Zn-coated steel sheet was established by the direct observation of the gas behavior in the molten pool with the high speed camera system. Main conclusions obtained are as follows: 1) Some blowholes were formed by incomplete back-filling to the pits at the last stage of the solidification. This type of blowhole was formed through four stages of gas in the molten pool, incubation, explosion, back-filling and completion of back-filling stage. 2) Most of the pits was back-filled at the last stage of their formation.