Suppression of temperature hysteresis in negative thermal expansion compound BiNi1−<i>x</i>Fe<i>x</i>O3 and zero-thermal expansion composite

Abstract

Negative thermal expansion (NTE) of BiNi1−xFexO3 is investigated. All x = 0.05, 0.075, 0.10, and 0.15 samples shows large NTE with the coefficient of linear thermal expansion (CTE) αL exceeding −150 ppm K−1 induced by charge transfer between Bi5+ and Ni2+ in the controlled temperature range near room temperature. Compared with Bi1−xLnxNiO3 (Ln: rare-earth elements), the thermal hysteresis that causes a problem for practical application is suppressed because random distribution of Fe in the Ni site changes the first order transition to second order-like transition. The CTE of BiNi0.85Fe0.15O3 reaches −187 ppm K−1 and it is demonstrated that 18 vol. % addition of the present compound compensates for the thermal expansion of epoxy resin.