When dealing with metal and metal fabrication, it is sometimes necessary to reduce residual stress. It is crucial to the overall strength and safety of a structure and lowers the risk of dimensional changes. Dimensional changes can greatly impact additional manufacturing and the final use of the metal. This quick guide will provide additional information on stress reduction. Let’s look at the benefits of stress relief and what types of materials need to be stress relieved.
Why Stress Relief?
Stress can build up during machining, cutting, and plastic deformation. The problem is that these stresses will eventually cause unwanted changes. The stress will attempt to release one way or the other. An uncontrolled release is when the stress releases naturally, which is detrimental to the metal and its future applications. This is why it is good to control the way in which the stress is relieved. This way, you can ensure that the integrity of the metal is preserved.
When Should You Do This?
It is a good idea to stress-relieve metal after rough machining. This should be done before final finishing, like polishing. You should also consider stress relieving metal that has parts with tight dimensional tolerances. When these parts are going to be further processed, stress relieving is highly recommended.
It is also a good idea to put welded structures through this process. This can help to decrease tension and increase the safety and durability of the structure.
How Do You Relieve Stress From Metal?
Let’s look at how do you relieve stress on metals using the annealing process. In order to complete this process, the metal should be heated between 550 and 650 degrees Celsius. The metal should then be soaked for two hours. The metal should then be cooled down slowly while still in the furnace or in the air. Slow cooling speed is crucial to avoid tension. You should pay special attention when stress relieving large pieces.
Final Thoughts
Stress relieving will not change the material’s structure. You should also know that this process will not ultimately affect the hardness of the metal either.
To preserve the hardness of the metal, it is important that the metal is tempered at about 50 degrees Celsius below the temps that were used in previous tempering sessions.
All safety protocols should be followed when stress relieving metals. These protocols do not change. Every step of metal tempering and treatment requires the utmost attention to safety.