THE RESIDUAL MAGNETIZATION OF A FERROMAGNETIC BODY MAGNETIZED IN AN OPEN MAGNETIC-CIRCUIT

A method of calculating the residual magnetization J(d) of articles ma de of medium-coercive materials (0.1 less than or equal to H-cs, kA/m less than or equal to 6) when they are magnetized in an open magnetic circuit is developed. The saturation magnetization J(s), the coercive force H-cs and the residual magnetization J(R) of the limit hysteresis loop, the demagnetization factor N and the strength of the external m agnetizing field H-e are used for-the calculation. The particular feat ures of the dependence of the maximum magnetization J(m) and the resid ual magnetization J(d) for bodies of different dimensions made of stee l, which are most widely subject to nondestructive testing, on the val ue of the applied magnetizing field is established. The effect of H-e on the sensitivity of J(d) to the parameters H-cs, J(R), N nnd H-e for articles of different dimensions and materials is analyzed. Recommend ations are made on choosing the methods of testing which ensure that J (d) is highly sensitive to the physical properties of the articles bei ng tested.