Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7882695 | Acta Materialia | 2014 | 9 Pages |
Abstract
Thermal vacancy behavior in B2-type FeAl was analyzed through thermal expansion, lattice parameter, and elastic modulus measurements. High-temperature X-ray diffractometry (HT-XRD) was conducted to determine the lattice parameter at elevated temperatures, and the electromagnetic acoustic resonance method was applied to investigate the temperature dependence of the elastic moduli in B2-type FeAl. Using a series of in situ high-temperature techniques such as HT-XRD and dilatometry, the thermal vacancy concentration at elevated temperatures was estimated from the divergence between the changes in the sample length and the lattice parameter with temperature, giving a vacancy formation enthalpy of â¼0.7 and 0.6Â eV for Fe-40Al and Fe-43Al (at.%), respectively. The long-range order parameter was found to increase with temperature in a high-temperature range, indicating that the Fe-atom recovery process occurs in this temperature range. The in situ high-temperature measurements suggest that at elevated temperatures, thermal vacancies have no significant influence on the lattice parameter and elastic moduli of B2-type FeAl.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Mi Zhao, Kyosuke Yoshimi, Kouichi Maruyama, Kunio Yubuta,