| 2006 №06 (11) | 2006 №06 (02) |
The Paton Welding Journal, 2006, #6, 2-6 pages
Role of keyhole in formation of deep penetration in a-tig welding of stainless steel
B.E. Paton, K.A. Yushchenko, D.V. Kovalenko, I.V. Krivtsun, V.F. Demchenko, I.V. Kovalenko
E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
Given are the results of experimental studies of size and shape of the weld pool in TIG and A-TIG welding of stainless steel of the 12Kh18N10T type (304H) using the surface arc with incomplete penetration. It is suggested that one of the causes of deep penetration in A-TIG welding is formation of a keyhole and associated change in intensity of Marangoni convection. Configurations of the free surface and bottom of the weld pool, which are characteristic of A-TIG welding, confirm this mechanism of deep penetration.
Keywords: TIG and A-TIG welding, arc, weld pool, penetration, keyhole, Marangoni convection, stainless steel
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