Magnetization and thermal expansion measurements have been performed on the series of
pseudobinary cubic Laves phase compounds Ho(Co1-xCux)2 for x=0, 0.05, 0.10, 0.20 and 0.30. The
magnetization and thermal expansion data show discontinuities at the ferromagnetic transition temperature,
Tc, for x-values between 0 and 0.10, indicating first-order transitions for these compounds. In the remaining
compounds a second-order transition is observed at Tc. This change is explained by a reduction of the
susceptibility of the Co, Cu sublattice at increasing x-values. The Tc-values for the series Ho(Co, Cu)2 are
compared with those for other RE(Co, Cu)2 compounds with RE=Gd, Tb and Dy. ?? 1986.
