High-Temperature Demixing Processes
High-temperature segregation processes separate alloying elements in liquid or solid phases, leading to undesired concentration differences and altered material properties.
Physicochemical Mechanism of Action
At high temperatures, alloying elements can be separated into different phases (liquid or solid). This occurs through diffusion processes, where atoms move from rich to lean areas and concentrate.
Metallurgical Relevance & Risks in Welding
This segregation can lead to uneven distributions of alloying elements. This can impair strength, toughness, and other material properties. In the weld, this can lead to cracks or hot cracks, which jeopardizes mechanical stability.
Workshop Practice & Instructions
To minimize segregation processes, it is important to ensure uniform thermal conductivity of the alloy. This can be achieved by choosing suitable welding methods and parameters. For high-temperature processes like TIG welding, careful control of temperature and cooling procedures is essential.