Investigations on magnetic, magnetocaloric and transport properties of Co2Ti1-xSn1+x (x = 0.25, 0.5) Heusler alloys

Abstract

Co2Ti1-xSn1+x (x = 0.25, 0.5) Heusler alloys have been prepared by arc melting technique and studied their magnetic, magnetocaloric and electrical resistivity properties. Magnetic studies show that x= 0.25,0.5 alloys order ferromagnetically around transition temperature Tc = 373.4 K, 375.8 K, respectively. Isothermal magnetization studies reveal the soft ferromagnetic nature and existence of ferromagnetic correlations above the transition temperatures of both alloys. Investigation of magnetocaloric properties results in the isothermal entropy change of 2.23 J/kg K and 1.58 J/kg K in an applied magnetic flux density change of ΔB = 5 T for x = 0.25, 0.5 alloys, respectively. Second order nature of the magnetic transition and easy tunability of magnetic properties with stoichiometry of Ti – Sn are favorable for magnetocaloric applications. Electrical resistivity studies reveal the metallic nature of both alloys and show negative magnetoresistance.