| 摘要 |
A method is provided for reducing the size and area coverage of surface carbides formed during the box annealing of steel strip. In one aspect the method includes providing a casting consisting essentially of, by weight percent, 0.08% max. carbon, 1.0% max. manganese, 0.06% max. aluminum, up to 0.1% max. chromium, up to 0.1% max. titanium, up to 0.1% max. niobium and up to 0.1% max. vanadium. The casting is hot rolled to strip and then cold rolled. After cold rolling the strip is box annealed at a temperature above the A1 temperature. The strip is cooled from the A1 temperature such that the rate of cooling is at least 30 DEG C./hour through the range of from about 727 DEG C. to about 700 DEG C. In another aspect the invention includes casting a steel of the aforementioned composition wherein the vanadium is at least 0.015%. The invention includes steel products made according to the methods just described.
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