Abstract: A duplex stainless steel includes less than, in weight percent, 3 percent nickel and 1.5 percent molybdenum. In one embodiment, the duplex stainless steel includes, in weight percent, up to 0.06 percent carbon; 15 to 25 percent chromium; 1 to less than 2.5 percent nickel; greater than 2 percent up to 3.75 percent manganese; greater than 0.12 up to 0.35 percent nitrogen; up to 2 percent silicon; up to 1.5 percent molybdenum; up to 0.5 percent copper; up to 0.2 percent cobalt; up to 0.05 percent phosphorous; up to 0.005 percent sulfur; 0.001 to 0.0035 percent boron; iron and incidental impurities. The duplex stainless steel provided may be provided in the form of an article of manufacture, such as strip, bar, plate, sheet, casting, tubing or piping. A method for making the duplex stainless steel of the invention also is disclosed.

Abstract: A ferritic stainless steel having improved high temperature mechanical properties includes greater than 25 weight percent chromium, 0.75 up to 1.5 weight percent molybdenum, up to 0.

Abstract: A method for producing a stainless steel with improved corrosion resistance includes homogenizing at least a portion of an article of a stainless steel including chromium, nickel, and molybdenum and having a PREN of at least 50, as calculated by the equation: PREN=Cr+(3.3×Mo)+(30×N), where Cr is weight percent chromium, Mo is weight percent molybdenum, and N is weight percent nitrogen in the steel. In one form of the method, at least a portion of the article is remelted to homogenize the portion. In another form of the method, the article is annealed under conditions sufficient to homogenize at least a surface region of the article. The method of the invention enhances corrosion resistance of the stainless steel as reflected by the steel's critical crevice corrosion temperature.

Abstract: A duplex stainless steel includes less than, in weight percent, 3 percent nickel and 1.5 percent molybdenum. In one embodiment, the duplex stainless steel includes, in weight percent, up to 0.06 percent carbon; 15 to 25 percent chromium; 1 to less than 2.5 percent nickel; greater than 2 percent up to 3.75 percent manganese; greater than 0.12 up to 0.35 percent nitrogen; up to 2 percent silicon; up to 1.5 percent molybdenum; up to 0.5 percent copper; up to 0.2 percent cobalt; up to 0.05 percent phosphorous; up to 0.005 percent sulfur; 0.001 to 0.0035 percent boron; iron and incidental impurities. The duplex stainless steel provided may be provided in the form of an article of manufacture, such as strip, bar, plate, sheet, casting, tubing or piping. A method for making the duplex stainless steel of the invention also is disclosed.

Abstract: A duplex stainless steel including, in weight percent, up to 0.06 percent carbon, 15 up to less than 25 percent chromium, greater than 3 up to 6 percent nickel, up to 3.75 percent manganese, 0.14 up to 0.35 percent nitrogen, up to 2 percent silicon, greater than 1.4 up to less than 2.5 percent molybdenum, up to less than 0.5 percent copper, up to less than 0.2 percent cobalt, up to 0.05 percent phosphorous, up to 0.005 percent sulfur, and 0.001 up to 0.0035 percent boron, with the remainder being iron and incidental impurities is disclosed. The duplex stainless steel may be included in an article of manufacture, such as a strip, bar, plate, sheet, casting, tubing or piping. A method for making such a duplex stainless steel is also disclosed.

Abstract: A method for producing a stainless steel with improved corrosion resistance includes homogenizing at least a portion of an article of a stainless steel including chromium, nickel, and molybdenum and having a PREN of at least 50, as calculated by the equation:

Abstract: An alloy having a composition, by weight, of about 0.025% or less carbon, about 0.5 to about 4.1% manganese, about 5.5 to about 6.2% silicon, about 11 to about 15% chromium, about 9.0 to about 15.5% nickel, about 0.8 to about 1.2% molybdenum and about 0.8 to about 2% copper and the remainder being essentially iron with incidental impurities. This composition results in lean alloy content in a high silicon austenitic stainless steel for concentrated sulfuric acid service while maintaining a corrosion rate similar to and competitive with existing alloys for such service. Acceptable characteristics were found when hot working was carried out in the range of about 2100.degree. F. to about 2200.degree. F. Annealing in the range of about 1925.degree. F. to about 2025.degree. F. is preferred, as is rapid water quenching after annealing.

Abstract: An austenitic alloy is provided having a desirable combination of properties by melting an alloy containing 25 to 27 weight percent chromium, 20 to 40 weight percent nickel, 5 to 7.0 percent molybdenum, 0.25 to 0.30 weight percent nitrogen, and the balance iron and incidental impurities. The alloys exhibit a CCCT value of greater than 49 degrees Centigrade, together with other desirable properties, can be so produced, while maintaining the level of resistance to stress corrosion cracking at a level higher than that of AISI Type 316L stainless steel.