Heat treatment is a controlled process used to alter the microstructure of metals and alloys such as steel and aluminum to impart properties which benefit the working life of a component, for example increased surface hardness, temperature resistance, ductility and strength. Heat treatment processes include case hardening, tempering, solution and ageing treatment, Specialty Stainless Steel Processes (S3P), annealing and normalising.
Steel parts often require a heat treatment to obtain improved mechanical properties, such as increasing increase hardness or strength. The hardening process consists of heating the components above the critical (normalizing) temperature, holding at this temperature for one hour per inch of thickness cooling at a rate fast enough to allow the material to transform to a much harder, stronger structure, and then tempering. Steel is essentially an alloy of iron and carbon; other steel alloys have other metal elements in solution. Heating the material above the critical temperature causes carbon and the other elements to go into solid solution. Quenching "freezes" the microstructure, inducing stresses. Parts are subsequently tempered to transform the microstructure, achieve the appropriate hardness and eliminate the stresses.
Here are several things to consider when heat treating metal:
l Different Methods Of Heat Treating Metal Produce Different Results
l Annealing And Heat Treating Are Not The Same
l Where You Heat Treat Is Another Factor
l Alloy Composition Can Affect Heat Treating — And Vice Versa
l It’s Important To Mention Heat Treatment Up Front
When heat treating metal, the methods and effects must be taken into account and shared with your manufacturing partners when you create the specifications for your small parts requirements. To learn more about maximizing the accuracy and effectiveness of your specs — and your budget, contact with us today.