Effect of annealing on the magnetic and magnetocaloric properties of Ni-Mn-In-B alloys as solidified ribbons

The structural, thermal, magnetic, and magnetocaloric properties of Ni$_{\mathrm{50}}$Mn$_{\mathrm{35}}$In$_{\mathrm{14.5}}$B$_{\mathrm{0.5\thinspace }}$melt-spun ribbons have been investigated using room-temperature x-ray diffraction (XRD), differential scanning calorimetry (DSC), and magnetization measurements. Magnetic and structural transitions were found to coincide in temperature leading to large magnetocaloric effects associated with the first-order magnetostructural phase transition. In comparison to the bulk and as-spun ribbon, both the martensitic transition temperature (T$_{\mathrm{M}})$ and Curie temperature (T$_{\mathrm{C}})$ shifted to lower temperatures on annealed Ni$_{\mathrm{50}}$Mn$_{\mathrm{35}}$In$_{\mathrm{14.5}}$B$_{\mathrm{0.5\thinspace }}$ribbons. Significant increase in magnetocaloric effect has been observed between the as-spun and the annealed ribbons. A comparison of magnetic properties and magnetocaloric effects in Ni$_{\mathrm{50}}$Mn$_{\mathrm{35}}$In$_{\mathrm{14.5}}$B$_{\mathrm{0.5\thinspace }}$as-spun ribbon, bulk, and annealed ribbon have been shown in detail. Acknowledgement: This work was~supported by the Office of Basic Energy Sciences, Material Science Division of the U.S. Department of Energy, DOE Grant No. DE-FG02-06ER46291 (SIU) and DE-FG02-13ER46946 (LSU).