High-performance LaFe11.6Si1.4H /Al composites for magnetic refrigeration: A good combination of magnetocaloric effect, mechanical properties, and thermal conductivity

Bulk LaFe11.6Si1.4Hy/Al composites with the saturated hydrogen content were prepared by hot pressing and subsequent hydrogenation. Al particles were dramatically deformed when pressed at 773 K, and a reaction of La(Fe,Si)13 and Al phases took place at 873 K. The reinforced skeleton structure consisting of malleable Al phases in the composites allows brittle La(Fe,Si)13Hy particles to be well bonded after hydrogen absorption. As a result, these LaFe11.6Si1.4Hy/Al hydrides show a good comprehensive performance for magnetic refrigeration, i.e., large entropy changes of 9.8–12.5 J/kg K under 2 T, large adiabatic temperature changes of 3.36–3.97 K under 1.9 T, high thermal conductivity of 11.4–45.6 W/m K, and high bending strength of 16.8–48.2 MPa. Particularly, the 20 wt% Al composite possesses a compressive strength of 122 MPa and plastic deformation of 4.6 %.