Gorbatenko V. Improvement of the structure of alloys for small section rolling mill rolls for the increasing its in-service resistance

Object of research: processes of deterioration of a material of working rolls calibres for small section mills at high-speed hot rolling. The purpose of research: a substantiation of rational parameters of composition and structure of alloys for manufacturing of working rolls with raised operational stability for high-speed rolling mills in view of change of the prevailing mechanism of deterioration of a surface of calibres depending on rolling speed. Methods of research - Metallografical and X-ray analysis, ultrasonic defectoscopy, mechanical tests. Scientific novelty: 1. It is established, that hard alloy working rolls the kind of the basic mechanism of destruction of a surface of calibres with increase of rolling speed changes from prevailing formation of a grid of a heat to prevailing abrasive wear process of a material. 2. Have received the further development of representation concerning influence of structural factors on a degree and features of wear process of a surface of roll's calibres fromhard alloys. 3. For the first time the opportunity of reception in high-carbon Cr-Ni- steel is established became the structure containing disperse, in regular intervals distributed in matrix carbides, in case of its slow cooling up to temperature below 800 C, and also at repeated heating preliminary quanched steel to the raised temperatures. Degree of introduction: results of researches have been used for improvement of composition and structure of materials for manufacturing of working rolls and bandages (in conditions of DONIX Ltd.), which establish in finishing and prefinishing groups of 150 and 250 mills with the purpose of increase of their service characteristics and replacements import rolls on the tool of a domestic production.