Copper than less-developed countries (30–40 kg per capita). The process of recycling copper is roughly the same as is used to extract copper but requires fewer steps. High-purity scrap copper is melted in a furnace and then reduced and cast into billets and ingots; lower-purity scrap is refined by electroplating in a bath of sulfuric acid. Numerous copper alloys have been formulated, many with important uses. Brass is an alloy of copper and zinc. Bronze usually refers to copper-tin alloys, but can refer to any alloy of copper such as aluminium bronze. Copper is one of the most important constituents of
Niobium alloy is also necessary to take care (e.g. hard chrome-plating of all copper tooling) to avoid copper contamination. Niobium alloy A niobium alloy is one in which the most common element is niobium. The most common commercial niobium alloys are ferroniobium and nickel-niobium, produced by thermite reduction of appropriate mixtures of the oxides; these are not usable as engineering materials, but are used as convenient sources of niobium for specialist steels and nickel-based superalloys. Going via an iron-niobium or nickel-niobium alloy avoids problems associated with the high melting point of niobium. Niobium-tin and Niobium-titanium are essential alloys for the industrial use