Large Magnetocaloric Effect and Magnetic Properties in ErCoAl

Magnetic properties and magnetocaloric effects of the intermetallic compound ErCoAl, crystallizing in the hexagonal MgZn2-type structure, have been investigated. This compound shows second-order ferromagnetic transition with Curie temperature T-C = 16 K. Around T-C, the maximum entropy change and relative cooling power are estimated to be 11.0, 15.5 and 18.5 Jkg(-1)K(-1) and 151, 284, and 433 Jkg(-1) for a field change of 30, 50, and 70 kOe, respectively. These experimental results suggest that ErCoAl could be an appropriate candidate for magnetic refrigerant working at the temperatures near 20 K.