Corrosion-resistant high-strength low-alloy steels
Abstract
Abstract Low-alloy steels having five to eight times the atmospheric corrosion resistance of carbon steels, 80,000 psi minimum yield strengths and an overall desirable balance of mechanical properties produced directly off the hot-mill have the following chemistry: carbon, .04 percent to .10 percent; manganese, .40 percent to 1.80 percent; sulfur, .03 percent maximum; aluminum, .015 percent minimum; chromium, .90 percent to 1.20 percent copper, .30 percent to .50 percent; silicon, .50 percent to 1.20 percent; phophorus, .10 percent to .15 percent; columbium, .015 percent to .040 percent; and zirconium, .04 percent to .12 percent or a total content of rare earth elements, such as cerium and lanthanum, such that the weight ratio of total rare earths to sulfur is at least 2.8 to 1. In processing the steel to strip or plate, it is hot-rolled so as to have a finishing temperature between its A3 temperature and 1,700* F, cooled at a rate between 20* F/sec. and 45* F/sec. and coiled or piled at a temperature of 1,100* F + OR - 100* F.
Inventors
- 👤 R Cover
- 👤 M Korchynsky
- 👤 J Bell
Bibliographic Details
Claims Analysis
Total Claims: 3References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
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