Model přirozeného deformačního odporu slitiny CuFe2 za tepla

Abstract

Bachelor thesis deals with the possibility of the description of hot flow stress with the Hensel-Spittel model. Experimental data were obtained from a series of uniaxial compression tests performed at deformation temperature of 650, 750, 850 a 950 °C and strain rates of 0,1, 1 a 10 s-1. The stress-strain curves were smoothed out in software Origin. Peak stress values were used to determine the value of activation energy in software ENERGY 4.0. From the remaining constants calculated by ENERGY 4.0 software, the peak stress and peak strain as a function of Zener-Hollomon parameter were mathematically described. The material constants of the Hensel-Spittel model were determined by multiple non-linear regression in software UNISTAT. Predicted values of hot flow stress showed relatively good accuracy at low temperatures. On the contrary, as the temperature increased, the Hensel-Spittel model hit its phenomenological phenomenon and was unable to predict the stress-strain curve more accurately.