A metallurgical system for producing metals and metal alloys includes a fluid cooled mixing cold hearth having a melting cavity configured to hold a raw material for melting into a molten metal, and a mechanical drive configured to mount and move the mixing cold hearth for mixing the raw material. The system also includes a heat source configured to heat the raw material in the melting cavity, and a heat removal system configured to provide adjustable insulation for the molten metal. The mixing cold hearth can be configured as a removal element of an assembly of interchangeable mixing cold hearths, with each mixing cold hearth of the assembly configured for melting a specific category of raw materials. A process includes the steps of providing the mixing cold hearth, feeding the raw material into the melting cavity, heating the raw material, and moving the mixing cold hearth during the heating step.

In various embodiments, a metal alloy resistant to aqueous corrosion consists essentially of or consists of niobium with additions of tungsten, molybdenum, and one or both of ruthenium and palladium.

A metallurgical system for producing metals and metal alloys includes a fluid cooled mixing cold hearth having a melting cavity configured to hold a raw material for melting into a molten metal, and a mechanical drive configured to mount and move the mixing cold hearth for mixing the raw material. The system also includes a heat source configured to heat the raw material in the melting cavity, and a heat removal system configured to provide adjustable insulation for the molten metal. The mixing cold hearth can be configured as a removal element of an assembly of interchangeable mixing cold hearths, with each mixing cold hearth of the assembly configured for melting a specific category of raw materials. A process includes the steps of providing the mixing cold hearth, feeding the raw material into the melting cavity, heating the raw material, and moving the mixing cold hearth during the heating step.

A niobium or niobium alloy which contains pure or substantially pure niobium 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 niobium alloy that is resistant to aqueous corrosion. The invention also relates to the process of preparing the niobium alloy.