Surface Deformation Micromechanics of Erosion Damage on SKD11 Alloy Steels

Abstract Although the abrasive wear behavior of SKD11 has been broadly studied, the performance of this material under severe erosive wear conditions remains insufficiently understood. Meanwhile, the erosive wear commonly occurs in vital engineering parts such as blade turbines, pump impellers, and piping systems. This study investigates the erosive wear mechanisms of SKD11 subjected to different heat-treatment conditions, namely as-cast, annealed, normalized, and quenched. The erosion test was conducted using a sandblasting apparatus at an impact angle of 30 deg, an air pressure of 0.49 MPa, and an exposure time of 600 s. Finite element analysis (FEA) was employed to provide further insight into stress distribution and deformation behavior during particle impact. The results showed that quenching reduced the erosion rate by approximately 26% compared with the as-cast specimen. Micro-cutting and micro-indentation were identified as the main erosion mechanisms. Micro-cutting features diminished with increasing material hardness, while micro-indentation became more pronounced in harder specimens. The oxygen element was detected on all eroded surfaces, indicating repeated impacts. However, the effect of oxygen was negligible owing to similar levels across specimens. FEA results reveal that extensive plastic deformation and elongated impact zones promote micro-cutting in softer materials, whereas limited plastic flow in harder materials favors micro-indentation. Overall, the quenched SKD11 exhibited the highest erosive wear resistance, and the lowest belongs to as-cast. The combined experimental-numerical approach provides new insight into the roles of contact time, rebound velocity, and absorbed energy in governing the erosion mechanism.