I am new in the forum; and I am currently studying physics at the high school level. I have a little problem... and I would greatly appreciate any help that you could provide me;

The thing is; I have to do an investigation on the relationship between magnetic flux density and temperature. My hypothesis is that when a ferromagnet is heated, the magnitude of B should decrease. However, I can't seem to find any formula which relates magnetic flux density and temperature, at least

**below**the Curie point (?). Is there a formula relating these? Thank you very much!