The article shows an influence of kind of tests on material hot defamation behaviour during physical modelling on Gleeble 3800. As material, high-strength low-alloy automobile steel HC420LA was used. Stress-strain curves and material constants based on results of flow stress and plain strain tests were calculated and compared. Besides finite-element modeling of rolling round bar on a smooth barrel was performed taking into account the calculated mechanical characteristics.
The paper is oriented toward the determination of constitutive equation constants by the inverse analysis of plane strain compression test results. The interpretation of such results is complicated by the inhomogeneity of strain rate distribution in the specimen caused by rigid ends, the lateral spreading of a specimen friction and the variation of temperature during the test. The results of plane strain compression tests of AISI-304 stainless steel are presented and significant deviations of temperature are observed at higher strain rates. Finite element simulation was performed to estimate the inhomogeneity of strain rate within the specimen and evaluate the effect of friction on the test results. Constitutive equations of the material were obtained by inverse analysis minimizing the deviations between the measured load values and the ones predicted by numerical simulation.