Long flexible melt-spun Ni-Co-Mn-In ribbons with shape memory effect and caloric perfomances above 300K

Abstract Magnetic shape memory alloys (MSMAs) and in particular Ni-Mn based Heusler materials are a new class of functional materials capable of magnetic-field-induced actuation, mechanical sensing, magnetocaloric and elastocaloric refrigeration as well as energy harvesting. However innovative ideas are needed to overcome many obstacles such as mechanical brittleness and materials shaping while having interesting functional properties. In the present work, flexible Ni45Co5Mn50-xInx ribbons with different x compositions have been developed by melt-spinning process. Good magnetic properties and bending strain up to 1 % are very interesting for the use of these ribbons as actuators, sensors or in the field of magnetocaloric cooling. Entropy variations of about 15 J / Kg.K under 5 T and a cooling recovery RCeff of 144  J / Kg can be obtained at around 300 K. Long ribbon lengths close to 20 cm with a two-way shape memory effect have been processed. We present a complete set of properties (magnetic, crystallographic, mechanical, actuating) for the optimal composition x = 12.5.