HOT-ROLLED STEEL FOR POWER GENERATOR RIM AND METHOD FOR MANUFACTURING SAME

摘要

A hot-rolled steel sheet for a generator rim contains a structure containing a ferrite phase with an areal ratio of 95% or more in which precipitates containing Ti and V whose average grain diameter is less than 10 nm are precipitated in crystal grains of the ferrite phase. The ferrite phase has an average crystal grain diameter within the range of 2 µm or more and less than 10 µm. The hot-rolled steel sheet for a generator rim has strength with a yield strength YS in a rolling direction of 700 MPa or more and electromagnetic properties with a magnetic flux density B 50 of 1.5 T or more and a magnetic flux density B 100 of 1.6 T or more.