Peritectic Segregation
Peritectic segregation is local demixing during the peritectic reaction where residual melts are trapped between phases. This leads to uneven phase distributions in the microstructure.
Physikalisch-chemischer Wirkmechanismus
Peritectic segregation occurs when a metal solidifies in a cooler state, resulting in uneven phase distribution. Residual melt trapped between phases leads to local segregation.
Metallurgical Relevance & Welding Risks
This segregation can cause an uneven structure, leading to increased hardness and toughness in certain areas of the material. This can cause cracks or hot cracks in the weld pool, especially when the metal is under high stress.
Werkstattpraxis & Handlungsanweisungen
To minimize peritectic segregation, it is important to ensure controlled cooling of the weld. This can be achieved by using cooling water or special cooling dies. The cooling rate should be set so as not to exceed the critical temperature range for the peritectic reaction. For metals with a high degree of structural change, slow and controlled cooling is especially important.