| 摘要 |
<p>A high performance weathering steel having a minimum yield strength of 70-75 ksi and a yield/tensile ratio less than about 85 is produced from a steel composition consisting essentially, in weight percent, of about: carbon 0.08-0.12 %; manganese 0.80-1.35 %; silicon 0.30-0.65 %; molybdenum 0.08-0.25 %; vanadium 0.06-0.14 %; copper 0.20-0.40 %; nickel 0.50 % max.; chromium 0.40-0.70 %; iron, balance except for incidental impurities; heating the steel to a hot rolling temperature, rolling the steel to a thickness about 2 times the final desired thickness, air-cooling the steel to a temperature of about 1800-1850 °F, recrystallize control rolling the steel with finish rolling at a temperature of about 1700-1750 °F, then water-cooling the steel to about 900-1200 °F, then air-cooling the steel to ambient temperature, to produce sections up to 90 feet or more, without further heat treatment.</p> |
