Heat-resistant Al-0.2Sc-0.04Zr electrical conductor

The combined effects of ageing and cold-rolling on the tensile and conductive properties of Al-0.2Sc-0.04Zr alloys were investigated. Both the tensile strength and electrical conductivity of alloys after cold-rolling + ageing or pre-ageing + cold-rolling + ageing treatments are apparently better than that of the only aged alloy; furthermore, the improvements on the properties made by pre-ageing + cold-rolling + ageing are slightly greater than that by cold-rolling + ageing. TEM observations indicate that the increase of strength should be associated with the formation of finer Al-3(ScZr) precipitates and substructure with boundaries pinned by nano-sized precipitates while the improvement of conductivity should be caused by the closure of microvoids. As an electrical conductor, the highest working temperature of Al-0.2Sc-0.04Zr with the best strength and conductivity can be as high as 345 degrees C. It strongly suggests that the Al-Sc-Zr alloy has a great application prospect in heat resistant conductor fields. (C) 2012 Elsevier ay. All rights reserved.