关键词: MT级钢帘线用盘条, 轻压下, 偏析, 珠光体团, 索氏体片层间距

Abstract: The chemical composition of C97D2-E wire rod for MT grade steel cord was designed by increasing carbon content and Cr alloying to improve the strength of cord steel. A new solidification heat transfer model was established by using Scheil-Gulliver solidification micro-segregation theory to guide C97D2-E continuous casting process， and the defects of central segregation， porosity and internal crack of continuous casting slab were solved. After optimization， the carbon segregation index of semi-finished product can be controlled within 1.05. The air-cooling process was optimized by using specially designed tuyere nozzle and“optiflex” device of Stelmor ， after air-cooling process optimization， the spacing between the layers of wire rod sorbite was obviously reduced， and the sorbite plate was more straight， the lamellar space of the rod was controlled at 89 nm， the particle size of the pearlite was more uniform and smaller， and the size of the pearlite was controlled at 20 μm； the tensile strength of finished steel wire reached 4 089 MPa， there was no delamination during torsion and no broken wire during laying to 5 000 m， which can meet the requirements of 2×0.30 MT steel cord.

Key words: Wire Rod for MT Grade Steel Cord, Soft Reduction, Segregation, Pearlite Nodule, Soxtenite Lamellar Spacing