Multi-material Inconel 718 – Aluminium parts targeting aerospace applications: A suitable combination of low-weight and thermal properties

Abstract

In this study, the combination of Inconel 718 (IN718) alloy, widely used in aerospace applications, and a highly conductive low-density Aluminium (Al) was hypothesized to achieve a disruptive solution with improved thermal conductivity and significantly lower weight, key aspects of aerospace industry. A multi-material IN718 - Al solution was designed and later fabricated by combining laser surface texturing and hot-pressing techniques. The multi-material IN718 - Al specimens were produced without significant defects and exhibited a significantly lower density than the IN718 bulk (<13 %), contributing to a weight decrease which can be considered strongly beneficial for improving energy efficiency of aerospace components. The Vickers' microhardness measurements were coherent results with literature and the interface between the two dissimilar materials exhibited a good metallurgical bonding with no significant diffusion of elements. The thermal conductivity of the multi-material IN718 - Al solution was 1.87 times higher than that of IN718 bulk. Multi-material IN718 - Al specimens have shown a high potential to decrease weight and enhance the thermal efficiency of an aerospace component.