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Phase transformation point

The phase transformation point marks the specific temperature in the phase diagram at which a thermodynamic restructuring of the crystal lattice takes place. Precise adherence to these points is essential for the thermal process management of iron alloys.

The transformation point is the temperature at which a metal's structure flips during heating or cooling – for example, from ferrite to austenite. In welding, it's important because the rapid cooling of the weld pool through this point determines what structure forms in the heat-affected zone. If you don't watch out, hard, brittle structure can form that's prone to cracking. So you've got to control the cooling rate to get a tough, crack-resistant structure.

MetallurgieSchweißtechnik

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