Critical parameters on sliding wear behavior in abradable sealing coatings

The abradability of ceramic-based abradable sealing coatings (ASCs) is exhibited as a sliding wear. We constructed a formula for the dimensionless function of wear rate based on the $\pi$ theorem. The interaction coefficient $\mu$, the actual intrusion depth $h_r$, and the porosity $p_{ASC}$ are the main variables influencing wear rate. The abradable process of the sealing coating was investigated by numerical finite element simulations and wear experiments. It was observed that the intrusion depth and wear rate show a trend of increasing and then decreasing with increasing porosity, while a similar trend is shown with wear rate. Both strain energy ($W_n$) and friction work ($W_f$) affect the wear rate. The wear rate of low-porosity coatings largely depends on strain energy, while that of high-porosity coatings is mainly influenced by friction work. This study has extracted key parameters that affect the high-temperature wear of sealing coatings, providing theoretical and experimental evidence for the preparation and performance assessment of coatings.