Quadruple-defect formation and changes of magnetic properties in cubic laves phases by milling

The structural and magnetic property changes induced by mechanical milling of GdPt2, which is a C15 compound, are studied. The results are compared to another C15 compound, GdAl2, that transforms to a spin glass under milling. Like GdAl2, GdPt2 remains crystalline while quadruple defects are formed. Instead of transforming to a spin glass it remains ferromagnetic at low temperatures, but under milling the Curie temperature drastically increases. There appears to be an almost linear relationship between the number of quadruple defects and the Curie temperature.