PRODUCTION OF ALUMINIUM-SILICON-MAGNESIUM WROUGHT ALLOY ROD WITH APPLICATION IN THE MANUFACTURE OF EXTRA-HIGH CONDUCTIVITY AAAC FOR OVERHEAD ELECTRICAL TRANSMISSION LINES

摘要

Aluminum-silicon-magnesium (Al-Si-Mg) wrought alloy rods have been used extensively in manufacturing stranded into wire conductors for high voltage transmission lines. Conventional All Aluminum Alloy Conductors (AAAC) have been produced using wire drawn from hot-rolled Al-Si-Mg rods. Midal Cables has slightly modified the production process for this type of rod in manufacturing of extra-high conductivity AAAC for applications as overhead transmission line conductors. These have lower DC resistance and thus have higher current carrying capacity. Midal Cables produces Al-Si-Mg alloy rods using the continuous casting and hot rolling process developed by Properzi. Modifications in the chemical composition, casting, and hot rolling parameters have produced a rod that reacts differently to heat treatment after wire drawing, resulting in a product that has higher electrical conductivity than conventionally manufactured Al-Si-Mg alloy wire used for the same application. The purpose of this paper is to discuss the production parameters used in manufacturing of Al-Si-Mg alloy rods and to establish the mechanisms that produce the extra-high conductivity property after wire drawing and heat ageing. This should help to understand the status and the future trends for this type of alloy and its applications in the power and energy transmission industry.