Question

The heating of metal to and holding at a suitable temperature and then cooled at a suitable rate for such purposes as: reducing hardness, improving machinability, facilitating cold working, producing a desired microstructure, or obtaining desired mechanical, physical, or other properties is known as:

Answer 1

Heat treatment of metals involves heating the metal to a specific temperature and then cooling it at a suitable rate to achieve desired changes in its properties.

Step-by-step explanation:

The process described in the question is called heat treatment of metals. Heat treatment involves heating the metal to a specific temperature and then cooling it at a suitable rate to achieve desired changes in its properties. This process can be used to reduce hardness, improve machinability, facilitate cold working, produce a desired microstructure, or obtain desired mechanical, physical, or other properties.

For example, in the case of steel, heat treatment can be done by heating it to a high temperature and then cooling it rapidly to obtain a harder and stronger material (known as quenching), or by heating it to a lower temperature and then cooling it slowly to obtain a softer and more ductile material (known as annealing).

Overall, heat treatment is an important process in metallurgy to manipulate the properties of metals to suit various applications.