Question

What is the Curie Point of Steel?

Answer 1

Hint: We need to know that the miscellaneous steel items like Nails, Screws, etc. are not magnetized normally, but they can become temporary magnets when exposed to magnetic fields. The iron present in certain types of steel is attracted to magnets and can acquire its own magnetism. This magnetism can be removed from steel screws and nails easily by heating them or by using demagnetizing objects/material.

Complete answer:
As we know that the curie temperature or curie point is the stage at which magnetic materials undergo drastic changes in their magnetic properties. This temperature is named after Pierre Curie, who discovered this in $1895$ and laid the laws of magnetism with change in temperature.
Below the Curie Temperature atoms behave as tiny magnets that align themselves in certain magnetic materials. In ferromagnetic materials the atoms in a domain align themselves in the direction of the field such that they reinforce each other. In anti-ferromagnetic materials, they align in an alternate opposite direction to the field, such that they cancel out each other. In Ferrimagnetic Materials the spontaneous arrangement is a combination of both patterns, and usually has two magnetic atoms, so that partial reinforcement of the magnetic field occurs. Increasing the temperature, for any of the types of magnetic materials in these three classes, disrupts the spontaneous arrangements and only a weak magnetic behavior remains known as Paramagnetism. On cooling these materials below their Curie Temperatures, the magnetic atoms again realign themselves so that Ferromagnetism, anti-ferromagnetism and Ferrimagnetism revives.
For low Carbon steel the curie point is \[770^\circ C\]. Above this temperature steel loses all of its magnetic properties and can become austenitic. On cooling below the Curie Temperature, however no residual magnetic field is observed for steel (i.e., it becomes demagnetised). Exposure to further magnetic fields will again magnetize it.

Note:
We need to know that the curie point for anti-ferromagnetic materials is called as Neel Temperature; the named is coined after the scientist who discovered this; Louis Neel in $1936$ successfully explained the concept of Anti-ferromagnetism.