Austenitic Grain Boundaries
Austenitic grain boundaries are interfaces between austenite grains where segregation and nucleation preferentially occur. Their size influences the recrystallization kinetics.
Physical-Chemical Mechanism of Action
Austenitic grain boundaries are interfaces between face-centered cubic austenite grains. On these surfaces, chemical segregation and nucleation processes can preferentially occur. The size of these boundaries influences how quickly the metal recrystallizes.
Metallurgical Relevance & Welding Risks
Large austenitic grain boundaries can lead to increased segregation of chemical additions, which can impair the hardness and strength of the weld. This can cause cracks and deformations in the material. Furthermore, uneven recrystallization can alter the structure and impair mechanical properties.
Workshop Practice & Instructions
To control austenitic grain boundaries, it is important to strictly adhere to welding parameters such as temperature and time. In high-performance steels, high hardness at the weld edge can result from insufficient recrystallization. It is therefore advisable to perform adequate post-weld treatment to increase recrystallization kinetics and ensure uniform mechanical properties.