Giant magnetic coercivity in CaCu5-type SmNi3TSi (T=Mn–Cu) solid solutions

•CaCu5-type SmNi3{Mn, Fe, Co, Cu}Si exhibit the Curie points at 12–190 K.•SmNi3{Mn, Fe, Co, Cu}Si show field induced transition at 6–110 K.•SmNi3MnSi shows huge magnetic hysteresis with coercive field of 80 kOe at 20 K.•SmNi3FeSi shows huge magnetic hysteresis with coercive field of 87 kOe at 40 K.•SmNi3CuSi shows giant coercive field of 54 kOe at 5 K.

The effects of transition metal substitution for Ni on the magnetic properties of the CaCu5-type SmNi3TSi (T=Mn, Fe, Co, Cu) solid solutions have been investigated. SmNi3MnSi, SmNi3FeSi, SmNi3CoSi and SmNi3CuSi show ferromagnetic ordering at 125 K, 190 K, 46 K and 12 K and field induced transitions at 65 K, 110 K, 30 K and 6 K, respectively. The magnetocaloric effects of SmNi3TSi (T=Mn, Fe, Co, Cu) were calculated in terms of isothermal magnetic entropy change (ΔSm). The magnetic entropy ΔSm reaches value of −1.1 J/kg K at 130 K for SmNi3MnSi, −0.4 J/kg K at 180 K for SmNi3FeSi, −0.37 J/kg K at 45 K for SmNi3CoSi and −0.5 J/kg K at 12 K for SmNi3CuSi in field change of 0–50 kOe around the ferromagnetic ordering temperature. They show positive ΔSm of +2.4 J/kg K at 30 K for SmNi3MnSi, −2.6 J/kg K at 65 K for SmNi3FeSi, +0.73 J/kg K at 15 K for SmNi3CoSi and −0.5 J/kg K at 6 K for SmNi3CuSi in field change of 0–50 kOe around the metamagnetic-like transition temperature. Below the field induced transition temperature, SmNi3TSi (T=Mn, Fe, Co, Cu) exhibits giant magnetic coercivity of 80 kOe at 20 K for SmNi3MnSi, 87 kOe at 40 K for SmNi3FeSi, 27 kOe at 20 K for SmNi3CoSi and 54 kOe at 5 K for SmNi3CuSi.

Graphical abstractCaCu5-type SmNi3MnSi, SmNi3FeSi, SmNi3CoSi and SmNi3CuSi show ferromagnetic ordering at 125 K, 190 K, 46 K and 12 K and field induced transitions at 65 K, 110 K, 30 K and 6 K, respectively. The magnetic entropy ΔSm reaches value of −1.1 J/kg K at 130 K for SmNi3MnSi, −0.4 J/kg K at 180 K for SmNi3FeSi, −0.37 J/kg K at 45 K for SmNi3CoSi and −0.5 J/kg K at 12 K for SmNi3CuSi in field change of 0–50 kOe around the ferromagnetic ordering temperature. They show positive ΔSm of +2.4 J/kg K at 30 K for SmNi3MnSi, −2.6 J/kg K at 65 K for SmNi3FeSi, +0.73 J/kg K at 15 K for SmNi3CoSi and −0.5 J/kg K at 6 K for SmNi3CuSi in field change of 0–50 kOe around the metamagnetic-like transition temperature.Below the field induced transition temperature, SmNi3TSi (T=Mn, Fe, Co, Cu) exhibits giant magnetic coercivity of 80 kOe at 20 K for SmNi3MnSi, 87 kOe at 40 K for SmNi3FeSi, 27 kOe at 20 K for SmNi3CoSi and 54 kOe at 5 K for SmNi3CuSi.Figure optionsDownload full-size imageDownload as PowerPoint slide