Effects of Iron-Millscale Addition on the Electrical and Thermal Properties of Aluminum-Nickel Alloy

Most alloys employed in the fabrication of metal-based heating elements are known to be plagued by low hot strength and debilitating embrittlement resulting in epileptic performance. In this study, electrical resistivity and thermal characteristics of iron-millscale (IMS) modified aluminium-nickel alloy were assessed for heating element application. The alloy was synthesised by adding varied IMS particles to the base aluminium-nickel mixture and cast in metal moulds. Cast samples were characterised for electrical resistivity, thermal stability and microstructural integrity using appropriate state of the art tools. The results showed that among the varied IMS additions, the 4 wt. % IMS particle samples exhibited the best performance in terms of thermal stability (345 oC), electrical resistivity (47.1-52.3 Ωm) under applied current in the range of 10-50 A. Contributions to these levels of properties enhancement stem from the inducement of quasi ferritic AlNiFe precipitates within the matrix