  Using the density functional theory (DFT) formulated within the framework of
the plane-wave basis projector augmented wave (PAW) method, the
temperature-dependent elastic properties of MgRE (RE=Y, Dy, Pr, Sc, Tb)
intermetallics with B2-type structure are presented from first-principles. Our
calculations are based on the fact that the elastic moduli as a function of
temperature mainly results from thermal expansion. The comparison between the
predicted results and the available experimental data for a benchmark material
NiAl provides good agreements. At $T=0K$, our calculated values of lattice
parameter and elastic moduli for MgRE intermetallics show excellent agreement
with previous theoretical results and experimental data. While temperature
increases, we find that the elastic constants decrease and approach linearity
at higher temperature and zero slope around zero temperature.
