Shear Stress
Shear stress acts parallel to the material plane and causes sliding processes in the crystal lattice, which enables plastic deformation.
Physical-Chemical Mechanism of Action
Shear stress is a mechanical force that acts in the material direction and excites the crystal lattice. It causes atoms or crystal planes to slide against each other, leading to plastic deformation.
Metallurgical Relevance & Welding Risks
If shear stresses are too high, cracks and material failure can occur. In the weld, this can result from inadequate stress distribution or excessive stresses during cooling. This leads to fine cracks that can propagate and destroy the material.
Shop Practice & Action Items
To minimize shear stresses, it is important to ensure uniform stress distribution during welding. This can be achieved through correct heat treatment and choosing the right welding technique. For high-strength steels or heavily loaded components, careful control of stress distribution is essential.