A Material Removal Model for KDP Crystal in Chemical Mechanical Polishing Based on Solid-phase Chemical Reactions

• • Theoretical material removal rates deviate from experimental values by ≤13% across all tested conditions, with maximum errors of 10.6% at 7.5 kPa and 12.5% at 30 kPa, validating the model's predictive capability for industrial process control. • • Material removal rate increases monotonically with polishing pressure (7.5–30 kPa) and pad rotational speed (40–80 r/min), enabling deterministic throughput scaling without sacrificing surface integrity. • • Mechanical action reduces the activation energy and elevates the contact-zone temperature, accelerating the solid-phase reaction rate; this coupling mechanism governs the chemical-mechanical equilibrium critical for high-quality KDP processing. • • The solid-phase reaction layer thickness, derived from the reaction rate model and single-abrasive scratching theory, directly determines abrasive penetration depth and material removal rate, providing a quantitative link between reaction kinetics and mechanical removal.