Relationship between remanence (B_r) and Magnetization (M)

[sgsawant]

Hi,

I have scoured through scores of websites but haven't found a reasonable solution. The thought problem goes like this. Take any NdFeB magnet which is saturated say to B_r =1.3 T. Is there a magnetization (M) value that corresponds to the this remanence. I have been able to find a few relations but then in the end I am still left with unknowns. For example χm (perhaps read as "Ki"). And even those are not easy to find for materials like NdFeB.

So the question is, is there a linear relationship between remanent field and magnetization? Many websites refer to magnetization as if it is the same as remanence. That I know for sure it is not.

Regards,

-sgsawant

 

[Gordianus]

If the magnet has a closed shape, like a torus, then the remanence field Br equals mu0 times the magnetization because the H field is null. In an open magnet the B field is less than Br.