Novel approach to high-strength, highly conductive Al-Mg-Si conductor alloys with Ag/Cu additions

Abstract

Al–Mg–Si conductor alloys with minor Ag and Cu additions were exposed to an effective and novel thermomechanical process to achieve high-strength, highly conductive alloys. The traditional thermomechanical process (TTMP) was modified with pre-aging at 120 °C for 24 h, creating the modified thermomechanical process (MTMP). The combined impact of the additional alloying with Ag/Cu and MTMP led to an increase in the strength by approximately 38 % (from 304 to 421 MPa), while achieving a minimum adverse effect on the electrical conductivity (EC) of approximately 4.9 % (from 51.1 % to 48.6 % IACS). The Ag/Cu-added alloys exhibited superior strength under MTMP with a reasonably moderate EC. Microstructural analysis revealed that nanosized precipitation is a promising factor for improving the strength of MTMP alloys. Tailoring the microstructure with these properties assists in the design of alloys and processes to obtain Al conductor cables with high strength and EC.