Investigation of magnetocaloric and magnetoresistance properties of co-based (Co0,402Fe0,201Ni0,067B0,227Si0,053Nb0,05)100-xCux (x = 0-1) glassy alloys

In this work, the magnetocaloric and magnetoresistance properties of amorphous Co-based (Co0,402Fe0,201Ni0,067B0,227Si0,053Nb0,05)100-xCux (x = 0, 0,5, 0,75, 1) ribbons were investigated. Cu additions changed the crystallisation temperature (Tx) and the Curie temperature (Tc). The saturation magnetisation (Ms) and coercivity (Hc) for alloys were in the range of 65,51–38,49 emu/g and 1,99–6,84 A/m, respectively. Under an applied magnetic field change of 2,2 T, the (-ΔSM)maks for (Co0,402Fe0,201Ni0,067B0,227Si0,053Nb0,05)100-xCux with x = 0, 0,5, 0,75 and 1 are 0,77, 0,71, 0,89 and 0,67 Jkg−1 K−1, respectively. The values of refrigeration capacity (RC) for the as-spun glassy alloys are comparable with those of previously studied Fe-based metallic glasses such as Fe80B10Zr9Cu1, (Fe0,76B0,24)96Nb4 and Fe82Ni2Zr6B10. In addition, the maximum magnetoresistance (MR) values for (Co0,402Fe0,201Ni0,067B0,227Si0,053Nb0,05)100-xCux with x = 0, 0,5, 0,75 and 1 are found to be 110,35 %, 37,48 %, 22,58 % and 1 % around the Curie temperatures under an applied magnetic field change of 1 T, respectively. With good RC, negligible hysteresis due to very low coercivity values and large magnetoresistance, these Co-based amorphous alloys can be used as the high temperature magnetic refrigerants and multifunctional applications working in the temperature range of 450–600 K.