Abstract
Development of new processes of plastic deformation of alloys and increasing possibilities of already existing ones is very often considered independently in two main categories: to obtain the required shape and quality of surface, or to obtain mechanical properties. Increasing expectations of recipients aimed at increasing quality of products cause that these problems must be consider simultaneously. It determines that designing of the technology of the processes should be realized this way that heat treatment of the material is performed during cooling after hot forming. Thus, such parameters of the process should be selected that complex structure and mechanical properties are obtained while high requirements of shape and surface quality are maintained. This objective cannot be reached without application of numerical modelling of phenomena, which take place during thermomechanical processing. The objectives of the present work are to contribute to development and testing of models describing behaviour of steels during deformation in the two-phase range of temperatures. The models for the carbon-manganese steel and microalloyed steel are described and tested. The effect of precipitation in the microalloyed steels on their behaviour is accounted for in the model.