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Information × Registration Number 0223U002490, 0122U000907 , R & D reports Title Investigation of the influence of local current pulses on the stress state of light alloys and resistance to destruction of their welded joints and the creation of optical-digital means for determining residual stresses popup.stage_title Head Lobanov Leonid M., д.т.н. Registration Date 21-02-2023 Organization E.O.Paton Elektric Welding Institute National Academy of scinces of Ukraine popup.description2  A new optical-digital system has been developed for the non-destructive determination of residual stresses based on laser interferometry methods used for displacement and deformation measurements that occur when high-density current pulses (108-1010 A/m2) are applied to the material. It is demonstrated that using high-density current pulses causes a local, non-destructive relaxation of stresses, similar to when drilling holes. The imprint of the electrode on the object's surface after the current pulse application has dimensions of less than 0.5 mm in diameter and up to 10 μm in depth, which allows this method to be considered non-destructive. The relationships between the surface deformation and the stress state were established on the specimens made from aluminum alloy 5056. The gathered experimental results were used to develop a mathematical model and algorithm for calculating the values of residual stresses using the high-density current pulse relaxation technique and laser interferometry measuring methods.Mechanical properties, fracture toughness, fatigue crack growth and fatigue life of butt-welded joints of aluminium alloy 2219 (Al-Cu alloying system) obtained by tungsten inert gas (TIG) were established. Shown that the tensile strength of the joints is 62...67% of the corresponding values of the parent metal, and the value of the stress intensity factor (SIF) for the weld metal is about 52% of the values of the parent metal. Plot of crack growth rate versus the stress intensity range of the base metal and weld metal of the joints were obtained, the parameters of the Paris equation were determined for their linear parts, and the corresponding critical values of the SIF were established. It was found that the fatigue limits of joints in the area of high cycle fatigue is about 75% of the corresponding values of the parent metal. Product Description popup.authors Bulash Volodymyr M Grishanov Arkady O Dyman Marianna M. Kadyshev Andrew Kyyanets Iryna V Klochkov Illya Vynnychuk Dmytro S. Kot Volodymyr H Lobanov Leonid Miryanin Volodymyr M Moltasov Andrii V. Motrunich Svyatoslav I. Savitsky Viktor V. Solovei Sergii O Tkach Iryna Tkach Pavlo M. Todorovich Nina L. Tsysar Maxim Shiyan Constantine V Shutkevich Alexei popup.nrat_date 2023-02-21 Close