Anti-Cracking Auxiliary
Anti-crack agents are chemical additives that bind sulfur and phosphorus and reduce hot cracking tendency. They increase process reliability.
Physical-Chemical Mechanism of Action
Anti-crack agents are chemical additives applied to the weld metal before welding, either as powders or coatings. These additives bind harmful trace elements such as sulfur and phosphorus. This binding reduces hot cracking tendency, since sulfur and phosphorus are known for their increased tendency to crack at high temperatures.
Metallurgical Relevance & Risks in Welding
Using anti-crack agents is crucial to prevent hot cracks. Sulfur and phosphorus can accumulate in the weld zone and cause severe cracking, especially at high temperatures. By binding these elements with additives, this tendency is reduced, increasing overall safety of the welding process.
Workshop Practice & Instructions
To apply anti-crack agents effectively, follow these steps:
1. Choose a suitable additive in powder or coating form.
2. Apply the additive to the weld metal before welding, e.g., by spraying or sprinkling.
3. Make sure the additive is well distributed and adheres to the metal.
4. Avoid excessive binding of the additive to the metal, as this could impair mechanical properties.