METHOD OF PRODUCTION OF RANDOM-ORIENTATION ELECTROTECHNICAL STEEL PLATES WITHOUT RISING DEFECT

摘要

FIELD: metallurgy.;SUBSTANCE: invention refers to metallurgy, particularly to production of random-orientation electrotechnical steel plates. The slab is made out of steel with the following chemical composition in wt %: C 0.005, Si from 1.2 to 2.2, Mn from 0.2 to 0.4, P 0.2, S 0.005, Al from 0.2 to 0.6, N 0.005, O 0.005, Fe and inevitable admixtures - rest, by melting in the converter, pre-treatment of hot metal by circulating affinage and continuous casting, at that cooling water quantity during secondary cooling is monitored ensuring its flow rate 100-190 l/min, and average level of liquid steel overheating during continuous casting is monitored at level 10-45°C. The slab is heated and subjected to hot rolling, including roughing and burnishing, at that the slab heating temperature is 1050-1150°C, temperature difference between two any points along the slab length during its heating is below 25°C, and input temperature of the burnishing process is at least 970°C. Etching by acid, cold rolling, annealing and coating application are performed.;EFFECT: produced steel plates have excellent magnetic properties and are not prone to rising defects.;5 dwg