Spannungsarmglühen

Spannungsarmglühen, also known as stress relieving annealing or tempering, is a heat treatment process used to reduce residual stresses within a material. These stresses can arise from various manufacturing processes such as welding, casting, forging, machining, or cold working. If left unaddressed, high residual stresses can lead to distortion, cracking, reduced fatigue life, and decreased dimensional stability of the component.

The process involves heating the material to a specific temperature below its lower critical temperature, holding it at that temperature for a predetermined time, and then slowly cooling it. The exact temperature and holding time depend on the material type, the magnitude of the residual stresses, and the desired outcome. During the heating phase, the material's yield strength decreases, allowing the internal stresses to relax. The slow cooling rate is crucial to prevent the reintroduction of new thermal stresses that could counteract the benefits of the annealing process.

Spannungsarmglühen is widely applied across various industries, including automotive, aerospace, and heavy machinery manufacturing. It is particularly important for components that undergo significant stress during their service life or require high dimensional accuracy. The effectiveness of the process is typically verified through methods like non-destructive testing or by observing the reduction in distortion after subsequent machining operations. It is a cost-effective method for improving the reliability and longevity of metal parts.