Welding residual stress

Welding residual stress refers to weldments in the welding process, the thermal stress, transformation stress, machining stress exceeds the yield limit (Yield strength), so that after cooling left weldment fails to eliminate the stress. In this way, the residual macro stress in the weldment after welding cooling known as residual welding stress. Uniform temperature field of the welding process and the organization of local plastic deformation and hematocrit caused by it is the root cause to generate the welded stress and deformation.

Welding residual stress, the key issues in the field of welding engineering. Various engineering applications involving welding, are very concerned about the impact of the residual stress. For example, in the field of civil engineering, connected for steel welding residual stress on fatigue performance of the structure, stability bearing capacity and so influential.
Cause
The workpiece casting, welding, forging, machining, and the residual stress generated in the interior of the workpiece in the manufacturing process such as heat treatment, straightening, and the presence of residual stress inevitably lead to some undesirable consequences.
Elimination
1, the natural aging
2, thermal aging
3, VSR VSR (currently with a) the substance of a resonance in the form of additional dynamic stress is applied to the workpiece, additional dynamic stress and residual stress superimposed meet or exceed the material yield limit, workpiece occurred microscopic or macroscopic plastic deformation, thereby reducing and averaging Chemical member internal residual stress, and its dimensional accuracy to achieve stability.