Hydrogen desorption temperature

If you have hydrogen in the structure after welding, you need to anneal the part so the hydrogen can diffuse out of the material. The temperature for this depends on the material – for steel, it's in the range where it's just not transformed yet. If you stay too cold, the hydrogen stays in and can later lead to cracks. It must not get too hot either, otherwise the structure coarsens and the part becomes soft. Stick to the specs for the respective material and let the part sit long enough at the right temperature.