Spontaneous magnetization
The ferromagnetic materials possess magnetic moment and thus magnetization even in the absence of the applied magnetic field, this magnetization is known as the spontaneous magnetization.
Spontaneous magnetization is stable only below a certain critical temperature called the Curies temperature, which is above the room temperature. Also, the spontaneous magnetization decreases as the temperature rises. But above the Curie temperature, the regular order of magnetic moments does not exist that is the atomic magnetic moments lie randomly oriented.
Reference: This article is referred from my book “electrical engineering materials” having ISBN 978-81-272-5069-0