THERMAL HYSTERESIS IN La(Fe,Mn,Si)_(13)-H ALLOYS

摘要

In this paper we present measurements of the specific heat c_p(H,T) and the entropy change Δ_s(H,T) on a set of La(Fe-Mn-Si)_(13)-H samples with variable Mn content in which the transition temperature changes from 269 K to 339 K. Our results permit to find the optimal compromise between a smooth transition with smaller entropy change and small hysteresis and a steep transition with higher entropy change but also larger hysteresis.