← Glossary

Heat-Affected Zone (HAZ)

The portion of the base material adjacent to the weld seam that has not melted, but whose microstructure and mechanical properties were altered by intense heat exposure.

The heat-affected zone is the area next to the weld where the structure has been altered by the heat. The width and properties of this zone depend heavily on the heat input and cooling rate. Depending on the steel grade, this can lead to hardening or embrittlement. So you have to choose the welding parameters so that you control the cooling, otherwise you'll get cracks or lose toughness.

MetallurgieSchweißtechnik

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