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Information × Registration Number 0218U000612, 0117U006064 , R & D reports Title PWI-2017/3 (Development of equipment and development of laser welding technology for complex profile thin-walled elements) popup.stage_title Head Shelyagin Vladimir Dmitrievich, Кандидат технічних наук Registration Date 05-02-2018 Organization E.O.Paton Electric Welding Institute of the National Acfdtvy of Science of Ukraine popup.description2 The object of research is the process of laser welding of thin-walled parts of the rocket's aerodynamic steering. The aim of the work was to develop equipment and practice laser welding technologies for thin-walled parts of the aerodynamic booster rocket; To design on the basis of the developed technologies a laser welding complex which can be introduced at the enterprises of the rocket-building branch of Ukraine. The analysis of modern developments in the field of welding thin-walled composite structures from high-alloy steels is performed. Prospective directions of conducting their own research have been determined, namely, to simplify the solution of the welding problem, the complex spatial trajectory of welding the aerodynamic booster of the rocket was conditionally divided into spatial primitives, that is, separate welded joints (butt joints, T-bridges, overlapping). This allowed us to consider the problems of laser welding of the aerodynamic rocket helm structure, from the position of welding of individual primitives. A variant of the aerodynamic rudder design was proposed in which four versions of welded joints of stainless steels were used: a butt joint with a thickness of both parts of 1.5 mm; butt joint, with a thickness of both parts 3.0 mm; lapping, with the thickness of the upper part 1.5 mm and the thickness of the lower part 3.0 mm; T-shaped, with a shelf thickness of 1.5 mm and a rib thickness of 3.0 mm. To prepare control samples of welded joints from thin-sheet high-alloy steels that meet the requirements of the current standards, a draft design was developed and mock-ups of technological equipment for laser welding: 1) T-welded; 2) butt and lapping; 3) angled welded joints. The testing of laser welding and repair modes for control welded T-joints, butt and lap joints from thin-gauge stainless steels was carried out on a laboratory bench based on Nd: YAG laser "DY044" (manufactured by ROFIN-SINAR (Germany)). Based on the results of visual, radiographic, capillary inspection and metallographic studies of the welded joints obtained, the parameters specified in the DSTU standard EN ISO 13919-1: 2015 were evaluated. Optimum modes of laser welding of welded joints (butt joints of 1.5 + 1.5 mm and 3, 0 + 3.0 mm; T-shaped (shelf) 1.5 mm + (rib) 3.0 mm, overlapping (top) 1.5 mm + (bottom) 3.0 mm). It is established that all samples subjected to the control correspond to the "high B" quality level, according to DSTU EN ISO 13919-1: 2015. According to the results of mechanical tests for static tension, it is established that the level of failure force of the controlled weld joints is not less than 0.8 from the force destruction of the basic material that meets the requirements imposed on such welded joints. The main causes of defects in laser welding of thin-walled welded joints from stainless steels have been established, and methods for their elimination and prevention of their formation have been proposed, namely: to eliminate defects in the form of pores, chains of pores, non-melting, impregnations, seam digestion, materials (if necessary); to prevent the formation of shrinkage shells and shells in the crater, - the use of discharge strips and filler materials; to eliminate undercuts, exceeding the convexity and exceeding the weld weld - performing additional melting with a defocused beam; to increase the critical section in a welded T-joint with a 1.5-mm shelf thickness and 3.0-mm-thick rib, - the use of a lens lens with a laser radiation splitter to expand the coverage area. The development of technological recommendations for laser welding of the elements of the aerodynamic booster design for the corresponding welded joints (butt joints 1.5 + 1.5 mm and 3.0 + 3.0 mm, T-pieces (shelf) 1.5 mm + (rib) 3,0 mm, overlapping (top) 1.5 mm + (bottom) 3.0 mm). A set of preliminary design documentation for the manufacture of a complex for laser welding of the elements of the aerodynamic booster design of the rocket was developed. In the future, a laser technological complex has been developed, it can be replicated for industrial implementation at enterprises of the rocket-building industry of Ukraine, in particular, at the Yuzhnoye Design Bureau. M.K. Yangelya "(Dnipro).5481 Product Description popup.authors Бернацький Артемій Володимирович Бондарева Валентина Іванівна Кузнець Олена Михайлівна Курило Володимир Андрійович Мащак Володимир Васильович Сіора Олександр Васильович Сучек Олександр Михайлович popup.nrat_date 2020-04-02 Close