In-situ EBSD investigation of plastic damage in a 316 austenitic stainless steel and its molecular dynamics (MD) simulations

The damage evolution process in 316 austenitic stainless steel at the plastic stage were investigated in this paper by using the in-situ EBSD technique and MD simulation in combination. The damage mechanisms of 316 steel are typified by an intergranular and intragranular mixed mode. The in-situ EBSD results showed that the intergranular damage was the defects formation at the GBs, and the twin-GB intersections and the triple GB are the preferred damage sites. While the intragranular damage was manifested by the mixing of lattice orientation change, intragranular flaws appearance, and twin degradation; The MD simulation results manifested that the initial lattice structure changed after the plastic strain, and the continues increase of the atom displacement resulted in the defect formation. The simulation results also verified that the twin-GB intersection site could be a fragile location, the void preferentially appeared here, and the disorder degree of atoms over here were great. In addition, the defects also generated at the triple GB, which indicated that the triple GB could also be a weak location.