The purpose of master’s thesis was to determine the effect of the degree of cold deformation on tensile strength Rm, yield strength Rp0,2, elongation A50, hardness by Brinell HB, deep drawing by Erichsen, earing and micro graininess on samples with thickness 0,50 mm in deformed state H18 and after laboratory annealing 290 °C/60 min. The purpose of master's thesis was also to determine the effect of iron and silicon, in alloy EN AW 8021B, on tensile strength Rm, yield strength Rp0,2, elongation A100 and deep drawing by Erichsen. Tensile strength Rm, yield strength Rp0,2 and hardness by Brinell HB are increasing linearly with the degree of cold deformation. Heat treatment greatly affects the elongation A50, which increases after the heat treatment. Erichsen's deep drawing values do not depend on the degree of cold deformation. In deformed state earing is rising with an increasing deformation, and after the heat treatment, earing is decreasing with increasing degree of deformation. The size of the crystalline grains decreases with the increasing degree of cold deformation after heat treatment. Iron has bigger effect on tensile strength Rm and deep drawing by Erichsen than silicon. Silicon has bigger effect on yield strength Rp0,2 than iron. Elongation A100 is affected by both, iron and silicon.
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