Recently, the first batch of the world's highest-strength-grade magnetic yoke steel, witnessed on-site by an expert team from a user, successfully passed quality acceptance. All indicators passed the rigorous inspection at one time, earning high recognition from the user. This marks a milestone breakthrough for Baosteel in the R&D field of magnetic yoke steel, providing key material support for the upgrade of global hydropower equipment. Faced with the demand for steel used in ultra-high-grade hydro-generator units, which requires the world's highest-strength-grade magnetic yoke steel with ultra-high requirements for plate shape quality and mechanical properties, and the need for optimal comprehensive indicators, relying on Baosteel's key core technology project platform, the Manufacturing Management Department of Tsingshan Base organized technical R&D personnel from the Technical Center, Hot Rolling Mill, and other departments to form a breakthrough team. They focused on full-process tracking and control, continuously organizing optimization of composition processes, and breakthroughs in plate shape and surface quality. After two months of multiple rounds of heat treatment process optimization experiments, all indicators of the physical quality met the user's acceptance requirements at one time.