A method for preparing high-purity nickel-based superalloy includes the steps of: performing electron beam smelting on small cylinders in a first water-cooled copper crucible after preheating an electron gun, and converging the beam to the edge of one side of the ingot; turning on the electron gun again after completely solidifying the ingot, the electron beam spot uniformly and slowly scanning a surface of the ingot from a side opposite to a final beam converging area of the ingot to the final beam converging area of the ingot to ensure that the alloy at a position scanned by the electron beam spot is completely melted, and stopping scanning once scanning to the final converging area of the ingot; casting the molten alloy in the first water-cooled copper crucible to the second water-cooled copper crucible; taking out the refined nickel-base superalloy after cooling down the electron beam melting furnace.

An electron beam melting furnace includes a hearth, a mold, an electron gun for keeping metal as a molten state, an electron beam controller for controlling direction of the electron beam, an image sensor for molten metal, and an operating device. A method for operating the furnace includes a step of inputting electron beam emitting coordinates in the electron beam controller, a step of emitting the electron beam, a step of detecting a high electron beam intensity spot by the image sensor, a step of calculating coordinates of high electron beam intensity based on the detected signal by the operating device, a step of calculating differences between the coordinates of emission and the coordinates of high electron beam intensity spot, a step of inputting the difference in the electron beam controller, and a step of controlling the location of electron beam spot.

A powder feeder system for a foundry system having a mixing hearth includes a housing assembly, and a feeder assembly in the housing assembly having a moveable barrel feeder for feeding a pre-weighed charge of metal powder into the mixing hearth of the foundry system during operation thereof. A method for recycling metal powder includes the steps of melting a content of the mixing hearth completely; and then feeding the metal powder into the mixing hearth while the contents of the mixing hearth are still molten using the powder feeder system.

A powder feeder system for a foundry system having a mixing hearth includes a housing assembly, and a feeder assembly in the housing assembly having a moveable barrel feeder for feeding a pre-weighed charge of metal powder into the mixing hearth of the foundry system during operation thereof. A method for recycling metal powder includes the steps of melting a content of the mixing hearth completely; and then feeding the metal powder into the mixing hearth while the contents of the mixing hearth are still molten using the powder feeder system.

A tantalum or tantalum alloy which contains pure or substantially pure tantalum and at least one metal element selected from the group consisting of Ru, Rh, Pd, Os, Ir, Pt, Mo, W and Re to form a tantalum alloy that is resistant to aqueous corrosion. The invention also relates to the process of preparing the tantalum alloy.

A tantalum or tantalum alloy which contains pure or substantially pure tantalum and at least one metal element selected from the group consisting of Ru, Rh, Pd, Os, Ir, Pt, Mo, W and Re to form a tantalum alloy that is resistant to aqueous corrosion. The invention also relates to the process of preparing the tantalum alloy.

A method for recovering a valuable substance is provided. The method includes a thermal treatment step of thermally treating a target, which contains a valuable substance and is stored in a target storing unit, via a flame blocking unit configured to block a flame for thermally treating the target such that the target storing unit is not contacted by the flame, and a valuable substance recovering step of recovering the valuable substance from a thermally treated product of the target obtained in the thermal treatment step.

A method for recovering a valuable substance is provided. The method includes a thermal treatment step of thermally treating a target, which contains a valuable substance and is stored in a target storing unit, via a flame blocking unit configured to block a flame for thermally treating the target such that the target storing unit is not contacted by the flame, and a valuable substance recovering step of recovering the valuable substance from a thermally treated product of the target obtained in the thermal treatment step.

A method of vacuum arc remelting an ingot provided in a crucible assembly having an electrode includes generating a rotating magnetic field normal to a longitudinal axis of the ingot and localized to an arc region during remelting. The rotating magnetic field interacts with a melting current to produce a rotating arc directed radially outward.

A tantalum or tantalum alloy which contains pure or substantially pure tantalum and at least one metal element selected from the group consisting of Ru, Rh, Pd, Os, Ir, Pt, Mo, W and Re to form a tantalum alloy that is resistant to aqueous corrosion. The invention also relates to the process of preparing the tantalum alloy.