Interstitial carbon content in iron crystallites
Interstitial carbon content describes how many carbon atoms fit into the octahedral gaps of the iron crystal lattice. This causes lattice distortion and increases the hardness of the steel.
Physical-Chemical Mechanism of Action
Carbon atoms are trapped in the octahedral gaps of the iron crystal lattice. This causes tetragonal lattice distortions, making the crystal lattice irregular and affecting its mechanical properties.
Metallurgical Relevance & Risks in Welding
Too high interstitial carbon content can lead to increased hardness and reduced ductility. This can lead to cracking risks and difficulties in forming the steel during welding.
Workshop Practice & Instructions
When welding steels with high interstitial carbon content, careful control of temperature and cooling rate is crucial. Too fast cooling can lead to glass-hard martensite formation, while too slow cooling leads to grain coarsening and reduced toughness.