Rhythm coordination at the steelmakingSteelmaking–continuous castingContinuous casting (SCC) interfaceInterface is essential for maintaining the stable operation of integrated steelSteel production processesProcess. This study addresses the problem of casting start time scheduling under steelmakingSteelmaking capacity constraints and proposes an intelligent decision-making method for continuous castingContinuous casting start times based on equipment capacity and metal resource characteristics. A feasible time domain model is first constructed based on the refining capabilities of multiple steelSteel grades and the scheduling rhythm of steelmakingSteelmaking charges. Then, casting start time matching strategies are developed by analyzing the sectional dimension requirements and casting speeds for different grades, in conjunction with the current accumulation levels of hot metal resources. A time-window constrained optimization model is formulated to determine casting schedules that balance steelmakingSteelmaking throughput, casting continuity, and metal resource flow. Industrial validation shows that the proposed method significantly improves resource utilization, enhances production rhythm coordination, and increases the efficiency of metal resource balancingResource balancing.