| 2006 №08 (08) | 2006 №08 (10) |
The Paton Welding Journal, 2006, #8, 29-36 pages
Structure of welded joints in tungsten single crystals
K.A. Yushchenko1, B.A. Zadery1, S.S. Kotenko1, E.P. Polishchuk1, O.P. Karasevskaya2
1E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.2G.V. Kurdyumov Institute of Metal Physics, NASU, Kiev, Ukraine
AbstractMethods of X-ray diffraction analysis and optical metallography were used to examine structure of tungsten single crystal (99.99 wt.%) subjected to local melting (welding) by the electric beam in vacuum. Data were obtained on crystallographic orientation of different zones of a welded joint relative to the base metal. Evaluation of density and distribution of dislocations in these zones was conducted. A zonal non-uniform multi-level distribution of dislocations in the welded joint was determined. Changes revealed in parameters of the dislocation ensemble are attributable to features of thermal-deformation processes occurring in welding
Keywords: electron beam welding, single crystal, welded joint, X-ray analysis method, crystallographic orientation, dislocation density, structural changes
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