Vladimir State University, Vladimir, Russia:

A. B. Lyukhter, Rectorate Councellor

LLC “Novye tekhnologii lazernogo termouprochneniya”, Vladimir, Russia:
А. N. Shlegel, Head of Laser Production, e-mail: shlegel@laser33.ru

Creation of a new generation of vehicles running on electric actuators associates with the problem of weight loss. This is necessary in order to achieve the dynamic performance comparable to the vehicles running on petrol or diesel fuel and increase speed. The problem is solved by reducing the total body weight or the individual housing parts using the lightweightmaterials such as aluminum. The use of aluminum alloy cladding in combination with a steel frame allows to improve the corrosion resistance and to reduce the vehicles weight significantly. Currently, steel is combined with aluminum by gluing, mechanically using rivets and welding. The progressive method of joining dissimilar material is laser welding, which is an indispensable tool due to the high degree of automation and the possibility of wide regulation of technological modes. Due to optimization of technological modes of laser welding it is possible to achieve high levels of durability of welded connection to alternating dynamic breaking load. The work is dedicated to the optimization of technological modes of laser welding of aluminum alloy sheets and structural steels. Welding was performed on laser robot systems consisting of ytterbium fiber laser with a power of 3 kW, and 6-axis robot arm with a positioning accuracy of ±0.07 mm. We defined the criteria of optimum parameters of technological modes of laser welding overlapped. The studies were aimed at determining the tensile strength, ductility, and discontinuity of the welded joint, depending on the technological parameters of laser welding lapped on the example of samples of aluminum alloy AMg2M and steel St3. We obtained the physical and mechanical properties of welds to get close to the alloy AMg2M. The optimal technological laser welding modes overlap the following pairs of welded joints having different thicknesses: ST3 + AMg2M, 3.0/3.0 mm; ST3 + AMg2M, 1.5/3.0 mm. We choose the most effective forms of welded joints capable of resisting shear on 360^о.

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