Tunable negative thermal expansion in La(Fe, Si)13/resin composites with high mechanical property and long-term cycle stability

Materials with tunable negative thermal expansion (NTE) are highly demanded in various functional devices. La(Fe, Si)13-based compounds promising NTE materials due to their outstanding properties. However, poor mechanical properties and related short service life restrict practical applications. In this work, epoxy resin positive is used synthesize La-Fe-Si/resin composites. The of composites can be manipulated by optimizing the La-Fe-Si particle size content, tailoring content could tune more effectively. average linear coefficient decreases from -275.0 × 10-6 K-1 -4.9 over magnetic transition temperature range as increases 3 wt.% 80 wt.%. addition, zero achieved composite 20 resin. would reinforce binding force filling pores between particles. exhibits improved properties; for example, its compressive strength 205 MPa 75% higher than that prepared machined into different shapes applications, such thin plates, strips, rods. Furthermore, undergo 1000 cycles without performance degradation integrity loss, indicating durable cycle stability. Hence, significantly high long-term stability makes present great application potential materials.