EFFECT OF ROLLING WITH REVERSAL ON THE PHYSICAL AND MECHANICAL PROPERTIES OF AD1 ALLOY SHEETS

The article presents the results of a study of the effect of changing the deformation direction of AD1 aluminum alloy sheets during cold rolling on the distribution of their hardness and specific electrical conductivity. Some of the initial blanks were deformed in the longitudinal direction, and some were turned 90° before the second pass. The effect of the deformation direction on changing the grain shape in the microstructure of rolled aluminum was established. During longitudinal rolling of sheets in one direction, the grain shape is elongated, their average length is 25 μm, and their width is 15 μm. After rolling with reversal, the grain shape is close to spherical, the grain size is about 20 μm. It is shown that during longitudinal rolling after two passes with a total reduction of 25%, in the center of the sheets, the specific electrical conductivity κ = 16,7 μS/m, hardness 39 HV; at the side edges κ = 24,2 μS/m, and the hardness 27,1 HV, the difference is about 44%. When rolling sheets with reversal, a less pronounced difference in the distribution of specific electrical conductivity and hardness is noted: in the central part κ ≈ 21,8 μS/m and hardness 23,6 HV, in the corners the maximum value of S is about 23,5 μS/m, hardness 25,3 HV, the difference is about 8%. An adequate linear equation has been obtained, which establishes a relationship between the specific electrical conductivity and hardness of deformed sheets. The use of the obtained dependencies expands the scope of application of operational non-destructive testing of the physical and mechanical properties of rolled aluminum. A positive effect of sheet rotation during rolling on increasing plasticity by 20% during shaping by stamping has been established. The research results can be used in developing rolling modes for sheet blanks for stamping high-quality parts from AD1 alloy at machine-building enterprises.