A strong ferritic high‐resistivity multicomponent alloy with tunable ordered coherent multicomponent nanoprecipitates

Abstract

We design and investigate a ferritic multicomponent alloy with high electrical resistivity, low temperature coefficient of resistivity (TCR) in a wide-temperature range, high strength, and moderate deformability, aiming to overcome the bottlenecks limiting the development of cost-efficient high-quality resistors. The developed bulk alloy with nominal composition Fe55Cr28Al12Ti3Si2 (at. %) shows a body centered cubic (BCC) matrix phase embedded with ordered coherent multicomponent nanoprecipitates in as-cast condition, which enables a high resistivity of 183 µΩ·cm, a low TCR of -35 ppm/K (from 298 to 673 K), a high yield strength of 1055 MPa, a high ultimate compressive strength of 1980 MPa and a moderate uniform compressive strain of 33% (at 673 K). The fully coherent and ordered multicomponent L21 nanoprecipitates in the BCC-α matrix enhance the stress required for dislocation propagation, leading to the improved strength and work hardening ability, according to the comparative study on the alloy variants with and without nanoprecipitates. Also, the multicomponent L21 nanoprecipitates enable the effective tuning of Kondo-like scattering and contribute to the low TCR of the material. The work thus demonstrates a design strategy for low-cost precision resistance alloys to achieve high and stable resistivity in wide temperature ranges combined with high strength and moderate compressive deformability by introducing well-tuned ordered coherent multicomponent precipitates in multicomponent alloy systems.