Working with steel can range from relatively easy to extremely complicated depending on the alloy. Carbon steel is the majority of steel produced as well as used in various industries, and it is typically alloyed with elements such as chromium, nickel or manganese as well as other metals.
Depending on the type of steel and the alloying elements used, annealing heat treatment for steel produces a range of different benefits and changes. The process of annealing steel is the same as for other metals; it includes a gradual heating cycle to a specific transition point, then a holding the steel at that temperature, which is known as soaking, followed by a precisely controlled cooling cycle.
Each of these three stages has to be very carefully selected based on the specifics of the steel in the part or component. The addition of the alloying elements impacts all three phases including heating, soaking and cooling.
Change the Grain Structure
By submitting steel parts and components to the annealing heat treatment for steel, the grains in the metal can move from coarser to finer, creating a denser and stronger physical property of the steel. This, in turn, allows the grains to align in the steel, reducing or relieving internal stress that can develop when steel is heated in the welding or working processes.
Increase Machinability
Through the annealing process, the steel becomes more ductile, which means it is easier to machine and to work with even cold forming types of processes. In the softer state, the steel is easier to work with for precision machining applications, helping to reduce costs as well as extend tool life.
Additionally, when the annealing heat treatment for steel is completed in a controlled atmosphere, the surface of the steel is resistant to oxidation. This is important in many industries and offers a lower cost option than other types of corrosion resistant finishes.