Welding stress

Welding stress, the stress is produced due to the welding and welded components. Changes in the shape and size of the weldment and soldering thermal stress generated during the welding process caused by weldment. Uneven temperature field of welding process and caused by its local plastic deformation and volume of different organizations is the root cause of the welding stress and deformation. When a non-uniform temperature field has not been caused by the disappearance of welding, welding pieces of this stress and deformation is called transient welding stress and deformation; stress and deformation temperature field called after the disappearance of the welding residual stress and deformation.

Welding stresses is including thermal stress and residual stress.

Thermal welding refers to the shape and size of stress changes in the welding process, the internal temperature of the weldment due to the stress caused by the difference, and soldering heat stress generated during the welding process caused weldment weldment. Uniform temperature field in the welding process and a partial specific volume of the plastic deformation and the type of tissue is caused by it to produce weld root cause thermal stress and deformation. When a non-uniform temperature field welding caused not disappeared, the presence of transient weldment welding stress and deformation; disappear there after welding temperature field of welding residual stress and deformation.

Welding residual stresses are not yet members already beginning to bear loads and stresses on the member section exists in the component service process, and other work load caused by the stress suffered by the superposition to produce a secondary deformation and residual stress redistribution, not only will reduce the stiffness and stability of the structure and the joint action of temperature and media, but also seriously affect the fatigue strength of the structure, resistance to brittle fracture ability, the ability to stress corrosion cracking resistance and high temperature creep cracking.