Below is a list of Heat Treating Furnaces manufacturers from Illinois. Heat treating furnaces heat a material and then bring it to a desired temperature. From there the material is cooled, which allows the furnace to instill increased strength, or aging within the material. This allows manipulation of the material to alter the physical, chemical and mechanical properties. The physical properties most often refer to how hard or soft the material is. Heat treating furnaces add billions of dollars per year in value to metal products, especially steel and nonferrous products, by imparting specific properties to the parts. These properties are often critical to the proper function of the heat-treated parts.