Kurpe O. Development of scientific bases of thermomechanical rolling of flat rolling products with obtaining the increased level of mechanical properties

The dissertation is aimed at solving an important scientific, technical and practical problem of expanding the range of products with the increased level of mechanical properties, which is produced on plate and strip mills. Problems and ways of further development of thermomechanical rolling processes have been determined, the systematization of technological stages has been performed. The method for calculating the temperature distribution over the width of the strip for rolling in the reversible stand with furnace coilers has been developed. For microalloyed steel of strength group X65 the dependence of the change of hot deformation resistance and austenite grain size on temperature-deformation parameters has been established. The conditions under which the rheological properties of 0X18MFT alloy and steels of grades 15X25T, DD11, 65G, X80, X70, St3sp are similar to the rheological properties of SSu lead has been established. The rolling conditions has been defined at which the maximum uniformity of deformation distribution on thickness of semi-rolled products is provided. Based upon clarification of heat losses calculation and taking into account the research results of influence of rolling temperature-deformation conditions on formation of the inherited mechanical properties of rolling, scientifically substantiated recommendations have been provided on development and implementation of the thermomechanical rolling technology of coils and plate rolling products of construction, pipe and shipbuilding product mix and as well as the calculation of the required level of technical characteristics for the equipment under the project of reconstruction at the strip rolling mill 1700.