Alloying element burn-off
Alloying elements like manganese or silicon vaporize and oxidize in the arc, leading to loss of these elements.
Physicochemical Mechanism of Action
Alloying elements in the base metal react with the intense light and high temperatures of the arc. They evaporate and oxidize, leading to a loss of these elements.
Metallurgical Relevance & Welding Risks
The loss of alloying elements can impair the mechanical properties of the weld. For example, strength and toughness decrease, which can lead to cracking and failure. Additionally, insufficient manganese content can coarsen the microstructure and reduce hardness.
Workshop Practice & Action Instructions
To minimize the loss of alloying elements, it's important to ensure a clean welding environment with good ventilation. Arc parameters like voltage and current should be set optimally. For special alloys, the use of shielding gases or the application of filler in the form of spray can be recommended.