Ledeburite
Ledeburite is the eutectic microstructure in high-carbon alloys consisting of austenite and cementite, which increases hardness but also brittleness.
Physicochemical Mechanism of Action
Ledeburite forms during cooling of carbon-rich alloys from austenite and cementite. It is an eutectic structure that arises from the simultaneous solidification of both phases.
Metallurgical Relevance & Risks in Welding
Ledeburite makes materials very hard and brittle. This can lead to hot cracking, especially if cooling is too fast. Too fast cooling can also result in a fine decomposition structure, further impairing mechanical strength.
Workshop Practice & Instructions
To minimize the risk of hot cracks and brittleness, controlled cooling should be ensured. This can be achieved by using a suitable shielding gas or applying a slow cooling technique. The maximum hardness of ledeburite can be influenced by carbon content and cooling rate.