Bauman Moscow State Technical University, Moscow, Russia:

B. F. Yakushin, Professor of a Chair “Technologies of welding and diagnostics”
I. N. Shiganov, Professor of a Chair “Laser Technologies in Mechanical Engineering”

Military-Industrial Corporation “Research and Industrial Association of Machine Building (MIC NPO mashinostroyenia)“, Reutov, Russia:
A. V. Bakulo, Chief Welder, e-mail: abakulo@yandex.ru

soft in the heat-affected zone because of overheating and degradation of strengthening intermetallic phases. This may be limited with heat input decrement when using new methods of welding, which cut the time of high-temperature overheating. When choosing alloys for new welded constructions, we take into account the mechanical properties of alloys, the strength factor of joints as regards the basic material and processability by various ways of treatment. However, the level of weldability of alloys (the main criterion of their fitness to high-quality defect-free welds) is not assessed quantitatively because of the insufficiency of methods for assessment of investigation of this behaviour in the new conditions. Our paper shows a new method for the choice of methods and conditions of welding of pressurized cylinders, made of heat-resistant and heat-strengthened alloys by simulation of welding conditions and operation of a welded joint in pressurized cylinder. The following tasks should be solved in order to achieve this goal: revealing the welding zones with high inclination to hot cracks in rigid attachments; influence of heat input on hot crack appearance and level of mechanical properties at various temperatures; comparison and choice of new welding methods by inclination to hot cracks. We show the results of investigation of weldability by choosing quantitative assessment of conditions and methods of welding, at which we can reach the maximum of mechanical properties of welded joints made of aluminium alloy 1151 and prevention of cracks when manufacturing the rigid model connections of pressurized cylinders for aeronautical engineering.

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