Abstract: Metal implants will be affected by force in the magnetic resonance environment, this paper's experiment measured all the spatial position of the magnetic field, combining with computer, found out the limit conditional position in the space available in the magnetic resonance environment. For devices below saturation, the location of maximum deflection is at the point where the multiply value of the magnitude of the magnetic field and the magnitude of the spatial gradient of the magnetic field is maximum. Above the magnetic saturation point, the maximum deflection will occur at the location where the magnitude of the magnetic field is maximum.