Cold rolling which is one of the most important technique in sheet steel forming causes stretching of microstructure and thus directionality of mechanical properties. This kind of directionality of mechanical properties is known as anisotropy which is, frequently, determined by R-value. One of the ways by which the phenomenon is controlled and optimized is recrystallization heat treatment. In this research the effect of microstructure directionality on the tensile properties of rolled sheet steel and also the influence of heat treatment parameters on the anisotropy behavior of St 52 steel were investigated. Tensile tests on the specimens at different directions, 0, 45 and 90 degree respect to the rolling direction were performed to determine R-value. Using the data average R-value, Rm, was obtained. The amount of anisotropy of the steel was measured by changing parameters such as time, temperature and cold work. It was determined that at constant time, increasing of recrystallization temperature causes reducing of anisotropy and this reduction would be promoted with increasing cold work. Also, it was demonstrated that at constant temperature, increasing of recrystallization time before grain growth causes reduction of Rm and after grain growth causes increasing of Rm.

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