Interstitial Solute Atoms
Interstitial foreign atoms are smaller atoms such as carbon, nitrogen, or hydrogen that occupy interstitial lattice sites and cause elastic lattice distortions. These distortions affect the mechanical properties of the metal.
Physical-Chemical Mechanism of Action
Interstitial foreign atoms are smaller atoms that lodge in the interstices of the metal lattice. They take the places of larger atomic cores and cause elastic lattice distortions. These distortions change the crystal structure and affect the freedom of movement of atoms in the lattice.
Metallurgical Relevance & Risks in Welding
The incorporation of interstitial foreign atoms can lead to enhanced mechanical properties, such as increased hardness and toughness. However, negative effects can also occur: carbon can lead to hot cracking if concentrated in the martensite region. Nitrogen can impair the durability of the weld, and hydrogen can lead to cold cracking (hydrogen-induced cracking).
Workshop Practice & Instructions
To minimize the risk from interstitial foreign atoms, it is important to use a clean welding environment and correct welding parameters. Use deoxidizers if necessary and pay attention to proper cooling technique. For high-hardness steels, special welding methods such as gas welding or plasma welding may be recommended to ensure controlled incorporation of foreign atoms.