High-temperature phase transition behavior and magnetocaloric effect in a sub-rapidly solidified La–Fe–Si plate produced by centrifugal casting

Abstract

A sub-rapidly solidified LaFe11.6Si1.4 plate was fabricated directly from liquid by centrifugal casting method. The phase constitution, microstructure and magnetocaloric effect were investigated using backscatter scanning electron microscopy, X-ray diffraction, differential scanning calorimetry and physical property measurement system. When the plate was annealed at 1373K, τ1 phase was formed by a solid-state peritectoid reaction. A first-order magnetic phase transition occurred in the vicinity of 188K, and the effective refrigeration capacities reached 203.5J/kg and 209.7J/kg in plates annealed for 1h and 3h, respectively, under a magnetic field change of 3T. It is suggested that centrifugal casting may become a new approach to prepare high-performance La–Fe–Si magnetocaloric plates for practical applications, which could largely accelerate the formation of τ1 phase during high-temperature heat-treatment process due to refined and homogeneous honeycombed microstructure.