Peritectic Reaction Line
Peritectic reaction line: During cooling, a liquid and a solid phase react to form a new solid phase. This is crucial for the microstructure of many steels.
Physicochemical Mechanism of Action
On cooling, a liquid and a solid phase react to form a new solid phase. This transformation step is what decides the structure of many engineering steels and alloys.
Metallurgical Relevance & Welding Risks
Cooling it the wrong way can stop the peritectic reaction from completing. That leaves you with an incomplete phase transformation and missing steel properties, like poor toughness or a higher risk of cracking.
Workshop Practice & Instructions
To make the peritectic reaction go through properly, cooling has to be controlled and slow. You can do this with cooling water or special cooling media. The exact cooling rate depends on the steel and the phase transformation you are after.