Patent attributes
The corrosion-resistant nickel-base alloy combines thermal stability with corrosion resistance and mechanical strength. The alloy contains balanced proportions of nickel, molybdenum, chromium, and iron with an effective amount of yttrium to stabilize grain boundaries against unwanted reactions, which might degrade corrosion resistance, and an effective amount of boron to maintain an acceptable level of ductility. The alloy may contain minor amounts of additives or impurities, such as silicon, manganese, and aluminum. The alloy may contain between about 25-45% molybdenum, 2-6% chromium, 2-4% iron, 0.01-0.03% boron, 0.005-0.015% yttrium, and up to a maximum of 1% manganese, silicon, and aluminum, respectively, by weight, the balance being nickel. It is preferred that the combined ratio of molybdenum, chromium, and iron to nickel be in the range of about 25% to 45%.
