Structural Stresses
Microstructural stresses are local mechanical stresses that arise during phase transformations. They occur when different metal phases have different volumes.
Physical-Chemical Mechanism of Action
During phase transformation, crystal structures change, and so does the volume of metal phases. These changes create local mechanical stresses within the microstructure.
Metallurgical Relevance & Welding Risks
Microstructural stresses can lead to cracks and fractures, especially if not properly relieved. They increase with temperature changes and can impair the microstructure, affecting the material's mechanical properties.
Workshop Practice & Procedures
To minimize microstructural stresses, controlled cooling is essential. This can be achieved by cooling the weld slowly and uniformly. For heavy metals like steel, a water bath or shielded air cooling is recommended.