Cu induced coercivity enhancement in the low viscosity GdCo5−xCux system

We investigate the influence of Cu substitution, on the coercivity and magnetic viscosity, in the ternary system GdCo_5−xCu_x (x=0, 0.5, 1, 1.5, 2 and 2.5) with different field sweep rates. All samples have been studied in the as cast state and crystallize in a single phase CaCu₅ structure. With Cu addition, the coercivity was 10 times enhanced for x =1.5. The behavior of the coercivity H_c against field sweep rate, dH/dt, shows that the GdCo_5−xCu_x system exhibits only a small magnetic viscosity effect, a desirable property for magnetic dynamic applications under high magnetic field.