Near-Zero Thermal Expansion And High Thermal Conductivity From Ambient To Cryogenic Temperatures In Hf0.87ta0.13fe2cux

Stable material properties against large and frequent temperature variations are strongly desired in modern industry. Here we report the combination of low thermal expansion, high thermal conductivity and good mechanical properties in Hf0.87Ta0.13Fe2Cux, all of which are well retained from ambient down to cryogenic temperatures. Cu partially substitutes for Hf/Ta atoms, causing a continuous suppression of negative thermal expansion. For x >= 1.25 the precipitation of Cu phase remarkably improves the overall thermal conductivity and compressive strength of the compounds. The excellent comprehensive performance covering such a broad temperature window suggests the wide applications of current composites, for example in cryogenic engineering.