SCHINDLER Ivo

Spoluautoři ŠUMŠAL Václav, KOPEČEK Jaromír, KAWULOK Petr, JÓZWIK Pawel, RUSZ Stanislav, KAWULOK Rostislav, OPĚLA Petr

Microstructure of the laboratory castings made from Fe-40at.% Al-Zr-B alloy was homogenized by the multi-pass hot rolling in protective capsules and by the subsequent long-time thermal processing. Based on the isothermal uniaxial hot compression tests and subsequent EBSD analysis of structure, the sufficiently accurate model describing the static recrystalization kinetics of the such prepared coarse-grained B2 iron aluminide after strain 0.2 was developed. The independent variables in this model are temperature of deformation as well as annealing time equal to the deformation temperature. Unexpected effect of the previous strain value on the static softening was observed, with the noticeable competition acting between recrystallization and recovery processes. Static recrystallization begins relatively easy in the studied alloy in the whole range of testing temperatures (900 – 1100 °C), but a very long-term annealing is quite necessary for the complete course of recrystallization. Heterogeneous course of recrystallization in the coarse-grained initial material yields in the selective growth of some new grains. High-temperature thermal processing after deformation must take several hours for obtaining the homogeneously recrystallized structure, which is unserviceable in the practical hot forming technologies.

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