Open AccessResearch of the influence of electron beam welding of titanium alloys on hydrogen distribution in the weld
Author(s) -
Vasily I. Muravyev,
Pavel V. Bakhmatov,
Vladimir Grigor'ev,
O. G. Shakirova,
S. A. Iskhakov
Publication year - 2019
Publication title -
vestnik samarskogo universiteta. aèrokosmičeskaâ tehnika, tehnologii i mašinostroenie
Language(s) - English
Resource type - Journals
eISSN - 2541-7533
pISSN - 2542-0453
DOI - 10.18287/2541-7533-2019-18-4-157-168
Subject(s) - welding , materials science , electron beam welding , heat affected zone , scanning electron microscope , composite material , titanium , titanium alloy , metallurgy , hydrogen , cathode ray , alloy , chemistry , electron , quantum mechanics , physics , organic chemistry
The paper presents the results of analyzing distribution of hydrogen in welded joints obtained by electron beam welding of titanium alloys VT20 and VT23. The distribution of hydrogen in the cross section of welded joints was measured in the area of the weld, in the heat-affected zone and in the base metal by means of spectral analysis using low-voltage pulse discharge on the spectrograph ISP-51. It was established that hydrogen peaks in fixed joints obtained by electron beam welding, unlike argon arc welding, are located not only in the heat-affected area, but also in the сentral part of the welded joint. Chemical analysis of fractures of fixed joints investigated with the aid of a scanning electron microscope Hitachi S-3400N showed that the pores in the welded joints made by electron beam welding occur due to the desorption of capillary-condensed contaminants located in the defects of the edge surface into the melt and due to selective grain boundary fusion because of insufficient temperature conditions of whole grain melting. It was found that emerging variations in hydrogen content, with formation of defects, are influenced by the temperature conditions of heating of the welded edges, the welding rate and the thickness of welded blanks.