The deformation and friction mechanisms of NiFeCr alloys based on molecular dynamics simulations

NiFeCr alloys are widely used in aerospace, marine and power equipment due to their good mechanical properties and wear resistance. At present, the relevant research on NiFeCr alloys mainly focuses on the design and preparation of the alloys, and there are relatively few studies on their mechanical behaviour and scratch deformation. In this paper, the effect of strain rate on the mechanical behaviour and scratch deformation of NiFeCr alloys is investigated using the molecular dynamics method. The results of tensile deformation under different strain rates show that when the strain rate increases from 2.5 × 109/s to 5.0 × 109/s, multiple slip systems are initiated simultaneously, and the entanglement of dislocations in different slip systems leads to dislocation stacking, and the strain rate enhancement effect is significant. When the strain rate is from 5 × 109/s to 7.5 × 109/s, the strain rate enhancement effect is not obvious. Further molecular dynamics scratching studies were carried out, and the results showed that as the scratching rate increased, the strain rate increased, the total number and length of dislocations increased, and the scratching force increased.