Interstitial Solute Diffusion
Interstitial solution diffusion is the process where small foreign atoms like carbon or nitrogen diffuse through the interstices of the metal crystal lattice. This happens under thermal activation and can lead to changes in material behavior.
Physico-Chemical Mechanism of Action
Interstitial solution diffusion refers to the movement of atomic molecules like carbon or nitrogen through the interstices (interstitial sites) of the metal crystal lattice. This diffusion occurs under the influence of heat and can lead to a change in the crystal structure.
Metallurgical Relevance & Risks in Welding
Interstitial solution diffusion has significant effects on material behavior. Too many carbon atoms can lead to increased hardness and lower ductility, which can cause cracking and fracture in the weld metal. An uneven loss or gain of nitrogen can affect strength and corrosion resistance.
Workshop Practice & Action Guidelines
To control interstitial solution diffusion, it is important to adhere strictly to welding temperatures and times. For steels with high carbon content (e.g., HSS), cooling should be slower to ensure a uniform distribution of carbon atoms. During heat treatments, care must be taken to set temperatures and times so that the material does not behave in an excessively critical manner.