The effect of hydrostatic pressure on magnetic properties of partially crystallized Co-based amorphous alloy

Melt-spun Co 66Nb 9Cu 1Si 12B 12 metallic glass ribbon (T C ≈150 K) was used to produce nanocrystalline samples by annealing at 590°C and 610°C for 1 h. Their magnetic properties were measured in a superconducting quantum interference device (SQUID) magnetometer as a function of temperature (10–250 K) in fields to 3 kOe at zero and ∼7 kbar hydrostatic pressure. The pressure shifts the Curie point of the amorphous matrix to lower temperature by −0.55 K/kbar. The difference between the zero-field-cooled (ZFC) and field-cooled (FC) dependences of the magnetization indicates mictomagnetic properties at low temperatures ( T< T C); for higher temperatures, the samples essentially are an assembly of superparamagnetic particles. The analysis of the Henkel plots for both samples points to the presence of interactions, whose sensitivity to pressure depends on the volume fraction of the crystallites.