Peculiarities of formation of structure of welded joints in arc surfacing with pulse feed of electrode wire

Abstract

2 Нац. ун-т кораблестроения. 54025, г. Николаев, просп. Героев Сталинграда, 19 Показано, что процесс дуговой наплавки в углекислом газе с импульсной подачей электродной проволоки по сравнению с постоянной ее подачей характеризуется повышенной стабильностью, меньшими потерями электродного металла на разбрызгивание и улучшенными характеристиками износостойкости наплавленного металла 30ХГСА. Установлен оптимальный диапазон параметров импульсной подачи электродной проволоки для наплавки -частота 10…30 Гц, скважность 3…5 ед. Показано, что уменьшение глубины проплавления основного металла достигается за счет снижения тока на стадии роста капли в элементарном цикле переноса электродного металла. С привлечением растровой электронной микроскопии выполнены сравнительные исследования микроструктуры наплавленного металла и зоны термического влияния при постоянной и импульсной подаче электродной проволоки при увеличениях ×500...2000. Библиогр. 18, табл. 2, рис. 10.К л ю ч е в ы е с л о в а : дуговая сварка, наплавка, импульсные алгоритмы, система подачи, электродная проволока, сварное соединение, микроструктура

"Investigation of the influence of low-frequency harmonic oscillations on deposited metal "

“…Over recent years quite a large number of works have been devoted to the investigation of microstructure formation under the conditions of periodic impact. This impact of the generator of oscillations or vibrations is most often imparted to weld pool melt by welding current [4][5][6], magnetic field [7,8], laser and electron beam [9][10][11][12][13][14][15][16], as well as the weld pool or tool [17][18][19][20][21][22][23][24]. Here, the respective increase of the degree of deposited metal microstructure dispersivity, compared to samples produced without peri-*Corresponding author: e-mail address: novykov76@ukr.net odic impact, essentially improves such service properties of the welded joint as-deposited metal hardness [4,11,13,19,22,24], wear resistance [5], impact toughness [4,20,24], brittle fracture resistance [4], and tensile strength [4,8,11,14,17,18,21,24].…”

“…This impact of the generator of oscillations or vibrations is most often imparted to weld pool melt by welding current [4][5][6], magnetic field [7,8], laser and electron beam [9][10][11][12][13][14][15][16], as well as the weld pool or tool [17][18][19][20][21][22][23][24]. Here, the respective increase of the degree of deposited metal microstructure dispersivity, compared to samples produced without peri-*Corresponding author: e-mail address: novykov76@ukr.net odic impact, essentially improves such service properties of the welded joint as-deposited metal hardness [4,11,13,19,22,24], wear resistance [5], impact toughness [4,20,24], brittle fracture resistance [4], and tensile strength [4,8,11,14,17,18,21,24]. Proceeding from the analysis of the data of these works, it can be roughly considered that the frequency range in modern studies is usually within 10 Hz [5]-27 kHz [24], that of amplitudes -6 µm [24] -0.5-2 mm [8,…”

“…Here, the respective increase of the degree of deposited metal microstructure dispersivity, compared to samples produced without peri-*Corresponding author: e-mail address: novykov76@ukr.net odic impact, essentially improves such service properties of the welded joint as-deposited metal hardness [4,11,13,19,22,24], wear resistance [5], impact toughness [4,20,24], brittle fracture resistance [4], and tensile strength [4,8,11,14,17,18,21,24]. Proceeding from the analysis of the data of these works, it can be roughly considered that the frequency range in modern studies is usually within 10 Hz [5]-27 kHz [24], that of amplitudes -6 µm [24] -0.5-2 mm [8,15,22]. However, it was experimentally proved that refinement of the deposited metal microstructure starts already at the frequency of 1.076 Hz at a deposition on carbon steel [25] by MMA and at 1.56 Hz and 2 mm amplitude at a deposition on the nickel-chromium alloy of Inconel 690 type without welding wire by GTAW [26].…”