Precision Steel Warehouse, Inc. Your Flat Rolled Steel Specialist 800-323-0740
Documents Contact Us

Heat Treating Steel

Heat treating steel is used to alter and change the physical & mechanical properties without changing its’ shape. These processes are used to increase or improve strength, hardness, toughness, machining, formability, ductility and elasticity. When heat treating steel & other metals, the various processes help make the metal more desirable for its application. These heat treating applications are essential in the manufacturing process. Precision Steel breaks down the differences between the heat treatment processes, including the common question of tempering vs annealing.

4 Types of Heat Treating Processes


Annealing is the process of heating a metal in a furnace above its recrystallization temperature and allows it to cool inside the furnace. First the temperature of the material is raised (say 912–915°C fore cast iron or steel). Secondly the material is soaked in that temperature for few hours. Third, the temperature is lowered and the material is allowed to cool inside the furnace. Annealing improves ductility, strength and good elongation properties.


Tempering is the heat treatment process which is done usually after quenching. In the process the material is heated to a temperature below the recrystallization value and held for few hours. This process removes internal stress and improves a bit of ductility to the hard material. Usually tool steels undergo this process to improve tool life.


The normalizing process is similar to that of annealing, but after soaking stage the material is taken out from the furnace and allowed to cool in atmosphere. The properties of the material are bit lower than that of annealing because of different cooling areas in the material.


Quenching is the process of heating the material above the recrystallization temperature and cooling it suddenly in a water bath or oil bath or in polymers. Type of quenching depends upon the application. Martensite matrix structure is seen in case of quenched materials. The material becomes so hard, more brittle and has the ability to withstand wear, vibrations. Abrasive resistance is more but can't handle creep and impact loads.

Click here to submit a Request for Quote
or call us today at 800-323-0740