Submicroscopic Residual Stresses
Residual stresses of the third kind are local stress fields at atomic lattice defects and dislocation lines that influence microscopic flow behavior.
Physico-chemical mechanism of action
Residual stresses of the third kind arise at atomic lattice defects such as cracks or dislocation lines in the material. These stress fields influence the microscopic flow of atoms and can lead to local deformation phenomena.
Metallurgical relevance & risks in welding
Residual stresses of the third kind can lead to local cracking or hot cracking if not properly addressed. They impair the hardness and toughness of the weld and can alter the microstructure.
Workshop practice & action instructions
To minimize residual stresses of the third kind, careful control of the melting process is required. Use uniform heating and cool the weld slowly. For higher hardness steels, post-weld heat treatment (PWHT) can help relieve the stresses.