Complete annealing and isothermal annealing, also known as weight crystallization annealing, are commonly referred to as annealing. This type of annealing is mainly used for casting, forging, and hot-rolled profiles of various carbon and alloy steels with hypoeutectoid compositions, and sometimes also for welding structures. Usually used as a heat treatment for some non heavy parts, or as a pre heat treatment for certain workpieces.

2. Spheroidal annealing Spheroidal annealing is mainly used for hypereutectoid carbon steel and alloy tool steel (such as steel grades used in the manufacture of cutting tools, measuring tools, and molds). Its main purpose is to reduce hardness and prepare for future quenching.

3. Stress relief annealing, also known as low-temperature annealing (or high-temperature tempering), is mainly used for residual stresses in castings, forgings, welded parts, hot-rolled parts, cold drawn parts, etc. If these stresses are not reduced, it will cause deformation or cracking of the steel part after a certain period of time or during subsequent cutting processes.