Superior overall performance of zero thermal expansion ZrW2O8/Al-Si composite

Zero thermal expansion (ZTE) materials show excellent dimensionally stability under temperature fluctuations, which are urgently demanded in high-precision devices. However, most ZTE materials display high density and narrow operating temperature. This study presents a lightweight ZrW2O8/Al-Si composite that not only exhibits ZTE of 0.79 x 10(-6) K-1 between 113 and 423 K, but also possesses an excellent high thermal conductivity of similar to 33 W/(mK), which is nearly two orders of magnitude higher than that of ZrW2O8. Furthermore, the continuous aluminum in the ZTE composite contributes to its good electrical conducting property (3.0 x 10(4) (Omega cm)(-1)), surpassing that of titanium (2.3 x 10(4) (Omega cm)(-1)). Simulated and calculated results confirmed that the in-situ nanoparticles at the interface play a crucial role in dispersing thermal stress, resulting in minimal susceptibility to thermal cycling-induced changes in thermal expansion and strength. The present study opens a new frontier for the development of high-performance ZTE materials.

Automated summary

Zero thermal expansion (ZTE) materials with excellent dimensional stability under temperature fluctuations are important for high-precision devices. This study has developed a lightweight ZrW2O8/Al-Si composite that shows both ZTE and high thermal conductivity, opening up a new frontier for high-performance ZTE materials.