High entropy alloys as strain-sensitive materials

Complex concentrated multi-element metallic systems, commonly referred to as high-entropy alloys (HEAs), exhibit a combination of unique physical properties when compared to conventional metallic materials. That makes this class of alloys promising for a variety of functional applications. However, HEAs are too expensive to be used for material-intensive products like structural materials, so their functionality can only be implemented in micro-scale applications. The electrical resistance sensors for detecting and measuring tension stress, pressure, micro-displacements, weight, and other physical parameters seem to be appropriate areas where HEAs could find their own place. This study addresses strain gauge characteristics in several HEAs, such as TiZrHfNb, TiZrHfNbTa, and FeCoCrMnNi (Cantor alloy). We discuss the pressure and strain gauge sensitivities in the systems employing experimentally measured electrical, magnetic, and thermal properties as well as ab initio calculations. We conclude that HEAs can be considered as promising materials for strain-sensitive resistance transducers that outperform commercial alloys in terms of a combination of performance characteristics.