What Does Heat Treating Entail?

Heat treatment refers to any kind of controlled heating and cooling operations used to bring about the desired change in the properties of a metal or its alloy. Its purpose is to enhance both the structural and physical properties of the metal for specific uses or for future purposes through the use of heat treating equipment. Heat treatment usually involves five processes, including hardening, annealing, case hardening, normalizing, and tempering.

Virtually, nothing can be fabricated without going through a heat treating equipment under tight controls. On one hand, it can soften the metal to improve its formability. On the other hand, it can also make metals a bit harder to improve its strength while putting a hard surface on relatively soft components to enhance resistance against abrasion. It can also provide protection to metals that could otherwise be corroded as well as toughen fragile parts.

Such capabilities are what makes heat treatment very useful for the operation and manufacturing of aircraft, automobiles, computers, and large equipment and machines. Almost all sorts of tools also depend on heat treatment processes such as axes, saws, gears, bearings, crankshafts, fasteners, and axles. The majority of heat-treated metals include iron and steel while the common alloys are copper, nickel, magnesium, aluminum, and titanium.

Heat-treating equipment can be used for multiple purposes. First, heating a metal part to a specific temperature. Second, holding it at a certain temperature for a specified amount of time. Third, allowing the part to cool down before moving it to another process according to prescribed methods. The high temperatures can go as high as 2400°F while the time varies depending on specific requirements, ranging from seconds to hours. Some metal parts can be cooled very quickly but most of them are being cooled slowly or being quenched using water, gases, oil, and polymers. Each has the specific qualities that make it suitable for certain applications.