DOI: 10.1002/aenm. 201500361 up to 20-times larger cooling powers per mass compared to
gadolinium (Gd), a benchmark magnetocaloric material, with comparable coefficient-of-
performance (COP) values (≈ 5). These results can open up a new way of making cooling
devices with much more compact systems and with the possibility of avoiding expensive rare-
earth materials. The martensitic transformation is a first-order solid-tosolid diffusionless
structural transformation responsible for the shape memory effect and superelasticity.[23] …