CRYOGENIC THERMAL EXPANSION AND ELECTRICAL CONDUCTIVITIES OF Mn3CuN CO-DOPED WITH Sb AND Sn

A series of Sb and Sn co-doped anti-perovskite Mn3CuN materials were fabricated by mechanical ball milling followed by solid-state sintering. Their thermal expansion properties and electrical conductivities were investigated in the temperature range of 77-300 K. The results show that Mn-3(CuxSb1-x) N (x=0.4, 0.5, 0.6, 0.7) exhibit negative thermal expansion (NTE) below 150 K, and the NTE temperature range shifts toward the lower temperature with the Sb increased. However, Sn doped in the Mn-3(Cu0.5SbxSn1-x) N can lead the NTE behavior shifts to room temperature and the NTE operation-temperature window (Delta T) becomes broader. The electrical conductivities of Mn-3(Cu0.5SbxSn1-x) N decrease with the temperature and Sb content increased.