Question

Thermal properties of a permanent magnet and electromagnet?

Answer 1

The former can be demagnetised by intense heat, as temperature destroys the alignment of the domains required for permanent magnetism.
In an electromagnet, the magnetism is caused by setting up an electropotential difference between two ends of a coiled wire, so that the resulting current, flowing in a helix, produces a toroidal magnetic field. As, short of melting all the wires and hardware or you, intense heat won't inhibit your ability to set up this potential difference and hence magnetic field for an electromagnet.