Peritectoid Reaction
Peritectectoid reaction: In the solid state, two phases react with heat input to form a new phase. This occurs in complex multi-component systems.
Physical-chemical mechanism of action
During a peritectic reaction, two different solid phases react at elevated temperature to form a new phase. This process is typical of more complex multi-component systems and requires careful control of the thermal conditions.
Metallurgical relevance & welding risks
This reaction can lead to undesirable phase formation that impairs the mechanical properties of the material. For example, it can cause increased hardness or deformability, which can lead to cracks or disintegration of the weld. It is important to ensure the correct heat treatment and proper filler metal content.
Shop practice & operating instructions
To avoid or control a peritectic reaction, the following measures must be taken:
• Heat treatment: The weld must be held in a specific temperature range to promote the desired phase formation.
• Filler metal content: The filler metal content in the metal must be precisely controlled to prevent or control the reaction.
• Temperature control: The temperature during welding and post-treatment must be precisely monitored and controlled.