OBRABOTKAMETALLOV Vol. 25 No. 1 2023 157 EDITORIAL MATERIALS cal application. Therefore, the development of the necessary special welding technology in low temperature conditions remains an urgent problem. The purpose of the work: to fi nd the ways to improve the reliability of high-duty metal constructions welded at low temperatures. The welded joints of 09G2S steel obtained by welding with direct current and pulsed low-frequency current modulation under conditions of positive (+ 20 °C) and negative (-45 °C) ambient air temperatures are investigated using three new types of welding electrodes. The methods of investigation. Mechanical tests for static tension and impact bending of welded samples, as well as spectral analysis of the chemical composition and metallurgical studies of weld metal are undertaken. Results and Discussion. It is revealed that the metal constructions operational factors depend on the choice of the welding method and welding temperature, as well as the characteristics of the welding material. It is established that to increase the impact strength of samples welded at negative temperatures by the adaptive pulse-arc welding method, an increase in heat input is required, relative to the rat of energy input, realized in the process of welding at positive temperature. The effect of the weld metal structure refi nement using adaptive pulse-arc welding with coated electrodes is confi rmed, including in conditions of negative ambient air temperature (down to 45 °С below zero). The presented results confi rm the prospects of the developed approach aimed at obtaining new classes of materials and products, intended for operation in the conditions of the North and the Arctic. _________________________________________________________________________________________________ Introduction The “Introduction” section should be used to defi ne the place of your work (approach, data or analysis) (up to 1.5-2 pages). It is understood that there is an unresolved or emerging scientifi c problem that is being addressed in your paper. In this regard, this section should provide a suffi ciently informed (with evenly distributed references to sources) literature review on the state of the indicated problem. Most of the links should be given in this section! At the end of the “Introduction” section, the purpose of the work is formulated and the tasks are indicated, the solution of which will allow achieving the set goal. 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