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Martensite

Martensite is a hard, brittle microstructure formed by rapid cooling of steel. Carbon remains trapped in the lattice, increasing hardness but also reducing toughness and dimensional stability.

Physical-chemical mechanism of action

Martensite forms when steel cools quickly. Carbon gets trapped in the lattice, which leads to a strong crystal structure and increases hardness.

Metallurgical relevance & risks in welding

Martensite makes the weld hard and brittle. This can lead to hot cracks and breakage, especially under mechanical stress. Toughness decreases, making the structure more prone to cracking.

Workshop practice & instructions

Avoid fast cooling when welding steels that may contain martensite. Keep the cooling time over 25 seconds to make the structure softer and tougher. Use suitable coolants or leave the part in a protected environment.

MetallurgieSchweißtechnik

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