Cold shortness
Embrittlement of metal at low temperatures, frequently caused by elevated phosphorus levels. Impact toughness drops significantly, leading to brittle failures at ambient or cold conditions.
Cold cracking means: the steel is no longer tough at low temperatures, but breaks suddenly, almost without deforming. The cause is often brittle microstructures like martensite or impurities such as phosphorus, which collect at the grain boundaries. Add residual stresses from welding – the whole thing can then crack without warning. So watch out for the material, especially with thick plates and low temperatures. Preheat the base material if the steel requires it, and don't let the weld cool too quickly. If necessary, stress-relieve by annealing. And remember: what holds in summer can break in winter – so don't forget the transition temperature.