Question

If steel is heated bright red hot, and is then cooled slowly, the process is called:
A.Quenching
B.Annealing
C.Tempering
D.Smelting

Answer 1

Hint:Annealing is a heat process in which a metal is heated to a specific temperature and then allowed to cool slowly. This softens the metal—so that it can be cut and shaped more easily.

Complete answer:
Steel is heated to bright red hot and allowed to cool slowly so that it can be shaped and cut easily. This process is known as Annealing.Annealing is a heat-treatment process that changes the physical and sometimes also the chemical properties of a material to increase its ductility, reduce the hardness and to eliminate internal stress. During the annealing process, the metal is heated to a specific temperature where recrystallization can occur. The metal is held at that temperature for a fixed period, and then cooled down to room temperature. The cooling process must be done very slowly to produce a refined microstructure, thus maximizing softness. It creates uniformity in a metal's grain structure, making the material stronger.

So, option-(B) is correct.

Additional Information:
Types of annealing processes:
-Complete Annealing. With this method, steel parts are heated until they're roughly 30°C hotter than their critical transformative temperature
-Isothermal Annealing
-Spherical annealing
Advantages of annealing includes- reduces the inner stress, increases Ductility, increases the toughness, improves the homogeneity, improves the agility, improves the material structure, reduces the hardness and brittleness, improves the magnetic property.The technological drawbacks include distortion during annealing as the process relieves all stresses.

Note:
-Quenching is the rapid cooling of a workpiece in water, oil or air to obtain certain material properties. Quenching is an important process that is used in the production of steel cutting tools.
-Tempering is a process of heat treating, which is used to increase the toughness of iron-based alloys. Annealing involves heating-steel to a specified temperature and then cooling at a very slow and controlled rate, whereas tempering involves heating the metal to a precise temperature below the critical point, and is often done in air, vacuum or inert atmospheres.
-Smelting is a process of applying heat to ore in order to extract a base metal. It is used to extract many metals from their ores, including silver, iron, copper, and other base metals.