As a magnetic field is applied starting from the origin (magnetic field: 0, magnetization: 0), magnetization is eventually saturated. The value at the time of saturation is called the “saturation magnetic flux density”. If the magnetic field is weakened in the opposite direction after saturation, the magnetic field becomes “0” on the vertical axis. The value of this intersection is called the “residual magnetic flux density”. If the magnetic field is further applied in the opposite direction after the intersection point with the vertical axis, magnetization becomes “0” on the horizontal axis. The value of this intersection is called “coercive force”.
The magnetization curve acquired when a magnetic field is alternately (including the opposite direction) applied to the magnetic body is called a “Hysteresis loop”.