Hot workability of an age hardenable nickle base alloy

In a method for producing an age hardenable nickel base alloy containing 17.5 to 18.5 percent chromium, 4.75 to 5.25 percent titanium, 2.25 to 2.75 percent aluminum, 14 to 15.5 percent cobalt, 2.75 to 3.25 percent molybdenum, 1 to 1.5 percent tungsten, 0.03 to 0.04 percent boron, 0.03 to 0.04 percent carbon, 0.02 to 0.05 percent zirconium, up to 0.1 percent columbium, up to 0.1 percent tantalum, up to 0.1 percent vanadium, up to 0.1 percent copper, up to 0.5 percent iron, up to 0.15 percent silicon, up to 0.15 percent manganese, up to 0.1 percent phosphorus, up to 0.0025 percent silver, up to 0.01 percent sulfur and the balance essentially nickel except for incidental impurities, and in which appropriate raw materials for producing an alloy of said composition are melted, refined, and thereafter cast into an ingot, the improvement which comprises improving the hot workability of the alloy by melting said appropriate raw materials under a vacuum in the presence of lime and forming a desulfurizing lime slag on the surface of the molten raw materials, and thereafter maintaining the molten raw materials under an inert gas atmosphere while adding magnesium thereto just prior to casting so as to obtain in the cast alloy a magnesium content of 10 to 100 parts per million and a sulfur content of no more than 50 parts per million.

An age hardenable nickel base alloy characterized by having excellent hot workability and consisting essentially of 17 to 20 percent chromium, 2.9 to 5.3 percent titanium, 1.8 to 2.8 percent aluminum, 11 to 15.5 percent cobalt, 2.5 to 7 percent molybdenum, 0.8 to 1.5 percent tungsten, 0.004 to 0.040 percent boron, 0.02 to 0.06 percent carbon, up to 0.05 percent zirconium, up to 0.1 percent columbium, up to 0.1 percent tantalum, up to 0.1 percent vanadium, up to 0.1 percent copper, up to 2 percent iron, up to 0.15 percent silicon, up to 0.15 percent manganese, up to 0.1 percent phosphorus, up to 0.0025 percent silver, no more than 50 parts per million sulfur, from 10 to 100 parts per million magnesium, and the balance essentially nickel.

An age hardenable hot workable nickel base alloy characterized by having excellent hot workability and consisting essentially of 17.5 to 18.5 percent chromium, 4.75 to 5.25 percent titanium, 2.25 to 2.75 percent aluminum, about 14 to 15.5 percent cobalt, 2.75 to 3.25 percent molybdenum, 1 to 1.5 percent tungsten, 0.03 to 0.04 percent boron, 0.03 to 0.04 percent carbon, 0.02 to 0.05 percent zirconium, up to 0.1 percent columbium, up to 0.1 percent tantalum, up to 0.1 percent vanadium, up to 0.1 percent copper, up to 0.5 percent iron, up to 0.15 percent silicon, up to 0.15 percent manganese, up to 0.1 percent phosphorus, up to 0.0025 percent silver, no more than 50 parts per million sulfur, from 10 to 100 parts per million magnesium, and the balance essentially nickel.