The magnetisation of antiferromagnetic materials depends on temperature. The magnetisation increases with the rise in temperature and becomes maximum at a particular temperature. Above this particular temperature, magnetisation decreases. This particular temperature at which magnetisation is maximum is called Neel temperature. Above the Neel temperature, the anti-ferromagnetic material becomes paramagnetic.
Reference: This article is referred from my book “electrical engineering materials” having ISBN 978-81-272-5069-0