Aktivační energie při tváření za tepla oceli AISI 4140

Abstract

Golasowski F. Hot deformation activation energy of steel AISI 4140 Ostrva: Department of Material Forming, VŠB-Technical University of Ostrava, 2019. 33 s. Bachelor thesis, head: : Ing. Stanislav Rusz, Ph.D. The bachelor thesis is focused on the determining of hot deformation activation energy of the AISI 4140 steel. In the theoretical part, I was aiming on the stress-strain curves, calculation of the activation energy, and the influence of the chemical composition on the activation energy. Uniaxial compression tests were being performed in the temperature range of 850 – 1250 °C and the strain rate range of 0.1 – 50 s−1 by means of the Gleeble 3800 plastometer. Hot deformation activation energy has been calculated in the ENERGY 4.0 software. Based on the comparison with the activation-energy value of the similar steel, it is evident that the activation energy of the studied steel is higher – especially thanks to the higher content of carbon and manganese.