Obrabotka Metallov 2023 Vol. 25 No. 4

292 OBRABOTKAMETALLOV EDITORIAL MATERIALS Vol. 25 No. 4 2023 ____________________________________________________________________________________________ An example of a structured abstract: Introduction. Welding aff ect fundamentally on the availability of the constructions operated under the low temperatures due to a decrease in resistance to the nucleation and propagation of cracks in the heat-aff ected zone and weld metal. Despite the existence of a suffi ciently large number of ways to improve the reliability of welded joints, some of them have now completely exhausted its capabilities, while others have not been brought to the stage of wide practical 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 eff ect 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. There is no need to write about a specifi c result in this section, since there is a corresponding section in the structure of the paper. METHODS / METHODS OF RESEARCH Theory (for theoretical works) or Experimental technique (for experimental works). One should avoid repetitions, unnecessary details and known provisions, detailed derivations of formulas and equations (give only the fi nal formulas, explaining how it was obtained. The rationale for the choice of this material (or materials) and methods for describing the material (materials) in this work are given. If necessary, drawings of samples with units of measurement are given (units of measurement in SI system only). When testing reference materials, reference to the standard is suffi cient. For a large test program, it is advisable to use a matrix-type table. If samples are taken from ingots, billets or components, then its orientation and location in the source material are described; standard designations according to the standard are used. During the tests, the following information is provided: 1. Type and conditions of tests, for example, test temperature, loading rate, environment; 2. Describes the variable parameters, measured values and methods of its measurement with accuracy, degree of error, resolution, etc .; for quantities that have been calculated, the methods used to calculate it. RESULTS AND ITS DISCUSSION A section contains a brief description of the experimental and/ or theoretical data obtained. The presentation of the results should consist in identifying the discovered patterns, and not in a mechanical retelling of the contents of tables and graphs. It is recommended to present the results in the past tense. The discussion should contain the interpretation of the research results obtained by you (correspondence of the results to the research hypothesis, generalization of the research results, proposals for practical application, proposals for the direction of future research).

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