Researchers at the State Key Laboratory of Solid Lubrication of the Lanzhou Institute of Chemical Physics of the Chinese Academy of Sciences have invented a new preparation method of copper-chromium intermediate alloy and received a Chinese invention patent for the technique on August 31, 2011. The patent is No. ZL200810184482.5.

Researchers first melted a reactive product by using the heat released from an aluminothermic reduction reaction. In the meanwhile, the melt was purified by the high-temperature and rapidly separated with the byproduct due to the density difference. And then the target material is obtained through a rapid cooling process. The copper-chromium intermediate alloy prepared this way has the characteristics of uniform structure, free of segregation and the like.

The new method is simple in technology and facilities, low in cost, and time-saving. And it is expected to be applied in fields like high speed railways and power transfer systems.

Previously reported preparation methods of copper-chromium intermediate alloy include high-energy ball milling in combination with powder metallurgy method, vacuum consumable arc melting, vacuum induction melting method, powder explosive compaction, etc. These methods are complicated in procedure, consume too much energy, and are hard to be accurately controlled. In particular, the prepared intermediate alloy has macrosegregation and non-uniform structure. All of these have limited the industrial application of copper-chromium alloy with high strength and high conductivity.