What describes the method of heating and cooling metals to enhance their properties?

The method of heating and cooling metals to enhance their properties is best described as heat treating. This process involves a series of controlled heating and cooling cycles designed to alter the physical and sometimes chemical properties of the material to improve its performance. Heat treating encompasses various techniques, such as hardening, tempering, quenching, and annealing, to achieve specific desired characteristics like increased hardness, strength, ductility, or toughness.

In contrast, hardening is a specific type of heat treatment that typically increases the hardness of a metal, while quenching refers to rapidly cooling a hot metal usually in water or oil to achieve hardening. Tempering is another specific process that follows hardening, which involves reheating the metal to reduce brittleness while maintaining a good balance of hardness and toughness.