Annealing stainless steel is a heat-treating process that actively improves the physical properties and even the chemical properties of metal alloys. Its main function is to reduce the overall hardness of the metal and increase ductility to make the metal more workable during processing.
The annealing process involves heating the alloy above its specific recrystallization temperature, maintaining that temperature for a predetermined time span, and cooling it down. This process is adjusted depending on what type of metal is being annealed.
The three stages of annealing are as follows: Recovery, Recrystallization, and Grain Growth. Grains develop during the first two phases, and the final phases fully develop those grains. The resulting softness from the anneal makes shaping and forming the metal much easier. Without annealing, the hard, brittle metal would split and crack, making it impossible to create certain products.
So how does this differ from tempering? Is it just a different name for heat treatment?
While tempering is a type of heat treatment, it does not have the same function as annealing. This process enhances the toughness of brittle metals to prevent damage during processing. Annealing, on the other hand, increases ductility and flexibility to facilitate metal shaping and forming.
The tempering process is fairly similar to annealing, however. It involves reaching a temperature slightly below the metal’s lower critical temperature, maintaining that temperature for some time, and cooling it at a specific rate. The temperature and rate of cooling are determined by the materials and the mechanical properties you need from the metal.
Some advantages of tempering include reducing internal stress, improving corrosion resistance, minimizing brittleness, and maximizing strength. Brookfield can produce steel wire with a full range of anneals and tempers. We also offer a full selection of quality metal alloys, so you receive the best wire for the job.