Eutectic ledeburite phase
Eutectic ledeburite phase is a hard and brittle structure of austenite and cementite that forms in iron with over 2.06 % carbon. It leads to poor mechanical properties and increases the risk of cracking.
Physical-Chemical Mechanism of Action
The eutectic ledeburite phase forms during rapid cooling of iron-carbon alloys with a carbon content above 2.06 %. In this phase, a mixed structure of austenite and cementite crystallizes, which is very hard and brittle.
Metallurgical Relevance & Welding Risks
The eutectic ledeburite phase leads to poor mechanical properties like low ductility and increased cracking risk. The hardness of this phase can cause hot cracks and decomposition in the weld area, affecting the lifespan and reliability of the component.
Workshop Practice & Handling Instructions
To avoid the eutectic ledeburite phase, the carbon content of the alloy should be kept below 2.06 %. When welding high-carbon steels, careful control of cooling and the use of proper welding procedures are essential. Slow and controlled cooling can help stabilize the structure and reduce the risk of cracks.