Proceedings of the 12th International Conference on Aluminium Alloys, September 5-9, 2010, Yokohama, Japan 2010 The Japan Institute of Light Metals Research of the Artificial Ageing Parameters Effect on Low-Temperature Creep of AlMgSi Wires Beata Smyrak, Tadeusz Knych, Andrzej Mamala 1 1 AGH –University of Science and Technology, Faculty of Nonferrous Metals, Al. Mickiewicza 30, 30-059 Krakow, Poland The hardened-precipitation type alloys AlMgSi grade 6101 of 0.5% Mg and 0.5% Si contents, are used for the construction of homogenous wires in overhead power lines. The suitability of these alloys lies in the characteristics of their electrical and mechanical properties within a wide range of heat treatment. Since alloys of this kind must meet certain standards with regard to creep resistance, the parameters for artificial ageing have to be controlled during the production process, in order to guarantee the appropriate rheological resistance. Therefore it is essential to define the impact of the separation fixing quantity on the material’s susceptibility to creep resistance. This paper presents the test results of the artificial ageing parameters on the creep characteristics of wires made of AlMgSi alloy produced from wire rod of T4 state, manufactured with the use of Continuous Properzi technology. The results enable us to formulate the duration of the artificial ageing process to achieve the required creep parameters of AlMgSi wires. Keywords: low temperature creep, AlMgSi, overhead power lines, rheological properties, precipitation hardening. 1. Analysis of the subject matter The global increase in demand for energy, and hence in transferred power, may lead to power line overloads and, consequently, in cascade outages of power supply systems, so called blackouts. This determines trends prevailing in the power industry, the mainstream of which consists in permanent search for solutions that lead to possible increases in transmitted power. Limited capacity of new power line procurement resulting from high costs and current building law is the cause for the search for cheaper alternative solutions. Most often existing power lines are upgraded by way of their rewiring with higher ampacity conductors. An effective approach to the subject issue is the application of homogenous wire designs that make the whole conductor section electrically active with no need to change its sizes. In addition such design guarantees uniformly distributed wire effort in each layer and eliminates internal stress resulting from the difference of the material’s thermal expansion coefficients. According to standard PN-EN 50183: 2000 (Overhead power line conductors – Bare conductors of aluminium alloy with magnesium and silicon content) [1] the following seven types are distinguished of wires for overhead line conductors (types A12 – A18). Figure 1 presents a graphical rendering of the said standard’s requirements. It may be noted that depending on their electrical resistivity the wires may be categorised in the following three groups: (i) low resistivity (30 n m), (ii) medium resistivity (31 n m), and high resistivity (32.5 – 32.8 n m). Tensile strength of these wires with 1.5 – 5 mm diameters amounts to 245–342 MPa [1]. The standards require the use of wire rod grade 6101 or 6201 after homogenisation, solution treatment in furnace and natural ageing (T4 treatment). In other countries AlMgSi wires are used that are based on similar content of the basic alloying components. Differences between them are in the initial stage and the wire rod to wire processing technology only. IEC standards that provide for requirements of wire rod, wires, and conductors, do not concern details of the alloys’ chemical 1585 Proceedings of the 12th International Conference on Aluminium Alloys, September 5-9, 2010, Yokohama, Japan ©2010 The Japan Institute of Light Metals pp. 1585-1590