Stacking Fault Energy
Stacking fault energy is the energy remaining in a metal due to a disturbed lattice defect. It determines whether cross-slip or twinning is preferred.
Physical and chemical mechanism
Stacking fault energy is the energy remaining in a metal due to a defect in the lattice. It results from a deviation from the regular stacking sequence of crystal planes. This energy can promote either cross-slip (movement of atoms within a plane) or twinning (creation of new lattice planes).
Metallurgical relevance & welding risks
If the stacking fault energy is too high, increased cross-slip can occur, which impairs the hardness and strength of the material. Twinning, on the other hand, can improve mechanical properties, but it can also increase the risk of cracking and damage.
Workshop practice & action items
To control stacking fault energy, it is important to strictly follow welding parameters such as temperature and time. For high-strength metals (e.g., steel), careful control of cooling is needed to minimize cross-slip. For materials with low stacking fault energy, twinning can be promoted through optimized welding processes.