Achieving zero thermal expansion over a wide temperature range in (Hf,Ta)(Fe,Cr)2 alloys
Year: 2025
Type: preprint
Abstract: Zero thermal expansion alloys possess significant potential for applications in aerospace, electronics, and optical instruments due to their volume remains nearly constant despite temperature changes[1,2,3]. Regulating and exploring zero thermal expansion alloys is crucial to mitigating thermal strain and stress. This study successfully adjusted negative thermal expansion alloy (Hf, Ta)Fe2 to zero thermal expansion over a wide temperature range by optimizing its composition and controlling the magnetic phase transition. Moderately substituting Cr for Fe transformed the giant negative thermal expansion (ΔT=15 K) into zero thermal expansion (ΔT=260 K). High-resolution synchrotron X-ray diffraction, macroscopic magnetic measurements, and linear thermal expansion measurements were employed to investigate the crystalline structures, magnetic properties, and thermal expansion of Hf0.84Ta0.16Fe2-xCrx (0 ≤ x ≤ 0.25). The alignment of the magnetic phase transition and anomalous thermal expansion temperature ranges demonstrates the essential role of spin-lattice coupling[4]. This work offers valuable insights into regulating zero thermal expansion behavior and explaining the applications of magnetic negative thermal expansion alloys. This advancement will promote their use in high-precision instruments, aerospace, microelectronics, and advanced manufacturing, enhancing device reliability and performance, particularly in extreme temperature environments[5,6].
Authors: chang zhou, Xiaobo Wang, Minjun Ai, Feixiang Long, Hong Zhong, Hao Lu, Jun Chen
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
OpenAlex ID: W4411244290