Maradványfeszültség

Maradványfeszültség, known in English as residual stress, refers to mechanical stresses that remain within a solid material after the original external forces have been removed. These stresses are locked into the material's microstructure and exist in the absence of any applied load. Residual stresses can arise from a variety of manufacturing processes, including welding, casting, forging, machining, heat treatment, and shot peening. They can also be induced by environmental factors such as thermal expansion and contraction or by plastic deformation.

The presence of residual stress can significantly affect a material's mechanical properties. Compressive residual stresses are generally beneficial, as they can increase fatigue life and resistance to stress corrosion cracking by counteracting applied tensile stresses. Conversely, tensile residual stresses can be detrimental, reducing the material's strength and making it more susceptible to failure.

Understanding and controlling residual stresses is crucial in engineering design and manufacturing. Techniques for measuring residual stress include X-ray diffraction, neutron diffraction, ultrasonic methods, and hole drilling. Methods for modifying residual stress profiles are also employed; for example, annealing can relieve residual stresses, while shot peening introduces compressive residual stresses. The careful management of residual stresses is essential for ensuring the reliability and longevity of components in various applications.