We recently answered the question: what is residual stress. As a follow-up for all of our interested readers, today we are addressing the topic of compressive residual stress. Once you understand the concept of residual stress, which is stress that is locked in a material during manufacturing, it is important to distinguish between compressive residual stress and tensile residual stress.
In a mathematical sense the term compressive residual stress refers to a negative residual stress condition. For example, if the residual stress condition at a particular location within a body has a value of -100 MPa, it is said to be in a state of compressive residual stress.
Engineers care about residual stress because it affects material performance. Fatigue cracking is one of the primary failure modes for many structures. Compressive residual stress can have a very positive impact on fatigue performance because it acts to resist the applied tensile stress as it holds the crack faces shut, minimizing damage.
To take advantage of this concept many compressive residual stress surface treatments have been developed. For example, shot peening, laser shock peening, and cold expansion are used to impart compressive residual stress, which can significantly enhance structural performance.
At Hill Engineering we are experts in compressive residual stress and how it affects material performance. We work with customers every day to improve, enhance, and optimize the performance of their parts using compressive residual stress. If you have any questions about compressive residual stress please contact us for more information. We’d be happy to write a future blog post expanding on your questions about compressive residual stress or other topics of interest.