Sulfur Segregation

Sulfur segregation is the enrichment of sulfur at phase boundaries and interstices during solidification. It promotes low-melting eutectics and increases hot cracking.

Physicochemical Mechanism of Action

Sulfur segregation occurs when sulfur concentrates at phase boundaries or in gaps during welding. This leads to local enrichment and can form low-melting eutectics.

Metallurgical Relevance & Welding Risks

Sulfur segregation raises the risk of hot cracks, because low-melting phases are less stable. This can lead to fine cracks or a coarse structure that hurts the toughness of the material.

Workshop Practice & Instructions

To minimize sulfur segregation:

• Cool the weld as fast as possible (t8/5 < 10 s).

• Use a suitable shielding gas to bind sulfur fumes.

• Watch the carbon content to ensure stable structure formation.

MetallurgieSchweißtechnik