Giant enhancement of magnetocaloric effect in metallic glass matrix composite

The magnetocaloric effect (MCE) has made great success in very low temperature refrigeration, which is highly desirable for application to the extended higher temperature range. Here we report the giant enhancement of MCE in the metallic glass composite. The large magnetic refrigerant capacity (RC) up to 103 J center dot kg(-1) is more than double the RC of the well-known crystalline magnetic refrigerant compound Gd5Si2Ge1.9Fe0.1 (357 J center dot kg(-1)) and MnFeP0.45As0.55 (390 J center dot kg(-1))(containing either exorbitant-cost Ge or poisonous As). The full width at half maximum of the magnetic entropy change (Delta S-m) peak almost spreads over the whole low-temperature range (from 303 to 30 K), which is five times wider than that of the Gd5Si2Ge1.9Fe0.1 and pure Gd. The maximum Delta Sm approaches a nearly constant value in a wide temperature span over 100 K, and however, such a broad table-like region near room temperature has seldom been found in alloys and compounds. In combination with the intrinsic amorphous nature, the metallic glass composite may be potential for the ideal Ericsson-cycle magnetic refrigeration over a broad temperature range near room temperature.