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Information × Registration Number 0220U101559, 0117U000356 , R & D reports Title To research the impact of electrohydraulic deformation of high-strength steels on the effect of yielding during sheet stamping and to develop a reccomendations on projecting technological processes that ensure high detail production accuracy popup.stage_title Head Kosenkov Viktor M., Registration Date 13-02-2020 Organization Institute of Impulse Processes and Technologies popup.description2  Object of studies – physical processes of elastic-plastic deformation and formation of sheet high strength steels at pulsed electrohydraulic loading. Methods of studies – experimental, mathematical and physical modelling. The impact of the speed of contact interaction between deformed HSLA350, DP780 and DP980 sheet high strength steels and the surface of matrix on the relaxation of tangent stresses in them as well as on the springing of parts, obtained by electrohydropulse stamping is studied. For the first time it is found that in conditions of preliminary uniaxial stretching up to the yield strength limit relaxation of tangent stresses in noted steels already starts when the speed of contact interaction with matrix is 5 m/s or higher, and when this speed has value of 30 m/s the level of tangent stresses relaxation has value between 0.36 and 0.5. The speed of contact interaction of 70-80 m/s is the limit, and when the speed becomes higher than this limit the value of contact stresses become too high, which are capable not only of compensating tangent stresses in stretched blank, but also of stretching it further, which causes pressing of the blank into the matrix with tension negative value of springing and increase of obtained part dimensions. Shockwave contact interaction between the blank and matrix at the speed of 200 m/s, which corresponds to the deformation speed of 80000 s–1 can also lead to the transformation of band-chaotic structure of high strength two-phase DP steels into the clearly band alternation of ferrite and martensite which include grinding of ferrite grains and almost two times increase of their relative elongation. Product Description popup.authors Zaychenko Andrii D. Kolomiytseva Lubov P. Kosenkov Viktor M. Tyschenko Fedir M. popup.nrat_date 2020-04-02 Close