Abstract
	The article analyses problems of defining the degree of softening from plastometric tests. There are described original evaluation programmes which have been developed by a composite author on the bases of deep knowledge of problems of the torsion plastometric tests. In the article, there are mainly suggested the basic principles of work with the pyX programme for evaluation of the degree of softening. Torsion intermittent tests have been carried out on a sample set of low-carbon steel on a torsion plastometer SETARAM-VÍTKOVICE. After evaluating of dependencies of the flow stress on deformation intensity with help of the SiPODeX programme, the definition of the degree of softening X followed by the programme pyX. This works on the principle of definition of residual deformation ????between individual partial reductions. The comparison of the individual tests suggests that factors influencing the degree of softening are e.g. temperature, whose increase means intensifying of softening, the length of the time lag when deformation interrupted, and as there was noticed on all samples after second deformations a higher degree of softening, it is clear that the intensity of softening is influenced by the power of the preceding deformation. When observing temperature of samples with 1 second time lag, it was found out that the degree of softening sharply rose at temperatures over 800°C, which proves previous claim about dependency of recovery on temperature. The most intensive recovery of these samples took place at the temperatures 860-1005°C. Samples with 6 sec. time dwell recovered at over 770°C because the material had more time for metadynamic recrystallization. From the evaluation of results in this work, we can state that by testing on a developed torsion plastometer hand in hand with programmes SiPODeX and pyX, it is possible to study carefully softening processes during deformations and pauses.