Effect of B doping on magnetic and mechanical properties of all-d-metal Heusler alloys

Abstract

The effect of trace doping on the magnetocaloric effect and mechanical properties of Ni36·5Mn35·5Co13Ti15Bx (x = 0, 0.1, 0.2, 0.3) are investigated. It is found that a small amount of B doping not only reduces the thermal hysteresis of the alloys, but also increases the magnetocaloric effect and mechanical properties. With increasing B doping, the transformation temperature of Ni36·5Mn35·5Co13Ti15Bx (x = 0, 0.1, 0.2, 0.3) increases from 273 K to 297.5 K. The alloy Ni36·5Mn35·5Co13Ti15B0.1 has large magnetocaloric effect with the thermal hysteresis of 7.5 K, isothermal magnetic entropy change and adiabatic temperature change of 37.8 J kg−1K−1 and 7.9 K under μ0H = 5 T, respectively. When x increases from 0 to 0.3, the maximum compressive strength increases by 29.8 %, from 1023 MPa of x = 0–1328 MPa of x = 0.3. It is also observed a large number of dimples and ligaments in the fracture surface for sample x = 0.1, indicating that the B-doped alloys have better toughness.