← Glossary

Blocky Ferrite

Blocky ferrite is a homogeneous, polygonal ferrite with large grain size. It forms during slow cooling from austenite and has low hardness and toughness.

Physical-Chemical Mechanism of Action

Blocky ferrite forms when austenite cools slowly. The atomic structure remains homogeneous and polygonal, without internal substructures like martensite or pearlite.

Metallurgical Relevance & Risks in Welding

Blocky ferrite has low hardness and toughness, which can lead to poor shapeability and potential cracking. It is especially dangerous under high loads.

Workshop Practice & Instructions

To avoid blocky ferrite, cooling of the weld pool should be fast. This can be achieved by high cooling water flow or special coolants. For steels with high austenite content, rapid cooling is essential.

MetallurgieSchweißtechnik

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