← Glossary

Boron hardenability effect

Boron reduces nucleation sites at grain boundaries, increases the depth of martensitic transformation, and improves the hardness of the weld.

Physico-Chemical Effect Mechanism

Boron reacts with the steel and forms a thin layer at the grain boundaries. This layer blocks the nucleation sites necessary for martensitic transformation. This increases the depth of martensite formation.

Metallurgical Relevance & Welding Risks

Too high a boron content can lead to fusion problems and a fine, glass-hard microstructure. This increases susceptibility to cracking and reduces material toughness.

Shop Practice & Instructions

Use boron in small amounts (about 0.01 to 0.05%) to improve hardness. Ensure the melting temperature and cooling time are optimally set to achieve homogeneous martensite formation.

MetallurgieSchweißtechnik

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