The residual induction is any magnetic induction that remains in a magnetic material after removal of an applied saturating magnetic field, measured in gauss or teslas, denoted as Br or Jr. Residual induction is also known as magnetic remanence.
From equation (1-1) we know, when H=0, Br =Jr. For rare earth permanent magnets such as Sm-Co and Nd-Fe-B, with the increasing of the reverse applied field H, the magnetic induction B decreases linearly in the second quadrant of demagnetization curve. Thus, any value of J or B on the second quadrant of demagnetization curve must be less than Br or Jr. This can also be comprehended as the material intrinsic magnetic polarization J cannot increase along with the inversely increased magnetizing force H.