The investigation of correspondence between molecular dynamics simulations and experiments of PTFE-PAI polymer coating with Si₃N₄

Traditional coating design suffers from time-consuming experimental processes. This study employs molecular dynamics (MD) simulations as an efficient alternative. Established an empirical mathematical relationship between experimental and MD data to enhance prediction accuracy and reliability. Using silicon nitride (Si₃N₄)-reinforced PTFE/polyamide-imide coatings as a model system, four compositions were designed: 0 wt%, 0.3 wt%, 0.9 wt%, and 1.2 wt% Si₃N₄. MD simulations predicted their friction coefficients and wear volumes. Ball-on-disc tests experimentally validated these predictions. Discrepancy mechanisms were investigated through hardness measurements, surface morphology analysis, and EDS mapping. A validation with an independently designed 0.5 wt% Si₃N₄ coating confirmed prediction errors below 10 %.