Delta-ferrite stabilizers
Delta ferrite stabilizers such as chromium, molybdenum, and silicon prevent the austenitic structure in weld zones and instead promote the ferritic structure. This improves hot crack resistance and hardness.
Physical-Chemical Mechanism of Action
Delta ferrite stabilizers are chemical elements that suppress the austenitic structure in weld zones. They instead promote the ferritic structure through their crystal structure and their effect on carbon content.
Metallurgical Relevance & Welding Risks
Using delta ferrite stabilizers in austenitic steels (like 1.4301) prevents the austenitic structure, increasing hot crack resistance and reducing cracks. However, too high a content of these elements can make the structure too rigid and impair formability.
Workshop Practice & Instructions
When welding austenitic steels with delta ferrite stabilizers, pay attention to the correct carbon content. Use a suitable welding method and temperature to stabilize the ferritic structure. Too high a carbon content can lead to a too rigid structure, impairing formability.