Many magnetic fusion reactor components will function in a strong magnetic field. The transient response of an elastic conductor containing a penny-shaped crack under an impulsive electric current flow and a constant axial magnetic field is analyzed. Numerical results on the dynamic stress intensity factor are obtained and are presented in a graphical form. If the ferromagnetic material is used in the magnetic field, we must consider the effect of induced magnetization. The transient response of a soft ferromagnetic thin plate under the action of impact is analyzed to show this effect. Numerical calculations are carried out and the influence of the magnetoelastic interaction on the dynamic behavior is discussed in connection with the fracture problem.