Achieving high-efficiency and stable refrigeration performance through composition modulation inducing non-twinned...

Area of Science:

• Materials Science
• Thermodynamics
• Solid-State Physics

Background:

• High-efficiency, eco-friendly refrigeration demands materials with optimal elastocaloric effects.
• Existing shape memory alloys face challenges balancing strain-dissipation work and driving force for coefficient of performance (COP_mat).

Purpose of the Study:

• To develop a novel single-crystal alloy for advanced refrigeration systems.
• To overcome the trade-off between driving force and energy dissipation in elastocaloric materials.

Main Methods:

• Investigated a Cu-18Zn-8Al-0.3V-0.3Si single-crystal alloy.
• Characterized recoverable strain, stress hysteresis, and driving force.
• Evaluated material stability over cycling and analyzed microstructure.

Main Results:

• Achieved a 13% recoverable strain with low stress hysteresis (8 MPa) under a minimal driving force (251.1 MPa).
• Demonstrated a high COP_mat of 17.4.
• Exhibited excellent stability over 800 cycles, attributed to unique microstructure and non-twinned martensite formation.

Conclusions:

• The novel alloy offers a synergistic optimization of energy efficiency and durability for refrigeration.
• Microstructure regulation, including ordered domains and distortion regions, is key to achieving low driving force and energy dissipation.
• Presents an innovative solution for next-generation, high-performance, and sustainable cooling technologies.