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Cooling Time t8/5

The time required for a weld and its heat-affected zone to cool from 800 °C to 500 °C. This parameter is crucial for establishing the microstructure and preventing undesirable phase transformations.

The cooling time t8/5 is the time the weld needs to cool from 800 to 500 degrees. It determines which microstructure forms in the steel – if you cool too fast, the material becomes hard and brittle; if you cool too slowly, the grain becomes coarse and toughness suffers. You have to choose the heat input and cooling conditions so that the cooling time lies in a window suitable for the respective steel.

MetallurgieSchweißtechnik

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