The magnetic properties and magnetocaloric effect (MCE) in the ternary intermetallic compound ErMn2Si2 have been studied by magnetization and heat capacity measurements. A giant reversible MCE has been observed, accompanied by a second order magnetic phase transition from paramagnetic to ferromagnetic at ∼4.5 K. Under a field change of 5 T, the maximum value of magnetic entropy change (−ΔSMmax) is 25.2 J kg−1 K−1 with no thermal and field hysteresis loss, and the corresponding maximum value of adiabatic temperature change (ΔTadmax) is 12.9 K. Particularly, the values of −ΔSMmax and ΔTadmax reached 20.0 J kg−1 K−1 and 5.4 K for a low field change of 2 T, respectively. The present results indicate that the ErMn2Si2 compound is an attractive candidate for low temperature magnetic refrigeration.

Dual-phase ErZn₂/ErZn composite was obtained by induction-melting method. The composite crystallizes in the phases of ErZn₂ and ErZn with the weight ratio of 53.8:46.2. The composite undergoes two successive magnetic phase transitions. And accordingly two peaks (partly overlapped) are appeared in the temperature dependence of magnetic part of entropy change ΔS_M(T) curves which resulting in a table-like magnetocaloric effect (MCE) and large refrigerant capacity (RC). The MCE parameters are comparable or even larger than most of the recently reported potential magnetic refrigerant materials at similar temperature region, making the dual-phase ErZn₂/ErZn composite attractive for low-temperature magnetic refrigeration. GRAPHICAL ABSTRACT IMPACT STATEMENT Table-like magnetocaloric effect (MCE) was realized in dual-phase ErZn₂/ErZn composite, the MCE parameters are comparable or even larger than most of the reported materials, making ErZn₂/ErZn composite attractive for magnetic refrigeration.