EFFECT OF ALLOYING ON THE GIANT MAGNETOCALORIC EFFECT OF GD-5(SI2GE2)

A study of the effect of different alloying additions substituting for nonmagnetic Si and Ge on the giant magnetocaloric effect observed for the compound Gd-5(Si2Ge2) revealed that small amounts (similar to 0.3 3 at%) of Ga raise the Curie temperature and preserve the giant magnet ocaloric effect. Larger quantities of Ga lead to a significant reducti on in the magnetocaloric effect, but the Curie temperature continues t o rise. Many 3d-metal and p-element additions also reduce the magnetoc aloric effect in Gd-5(Si2Ge2) due to the changes in the thermodynamic nature of the magnetic phase transition. In general, all alloying addi tions raise the Curie temperature of the parent Gd-5(Si2Ge2).