###### Abstract  
In micro-abrasive water jet polishing (MAWJP) technology, where abrasive particles serve as polishing tools, particles tend to form large clusters, leading to increased nozzle wear and diminished material polishing quality. Achieving a polishing solution with good dispersion stability is crucial for enhancing polishing accuracy and minimizing nozzle wear. Therefore, this study employed three dispersants with distinct dispersion mechanisms to examine the impact of each dispersant's concentration on the dispersion stability of the polishing solution across various abrasive concentrations. Through experimentation, the optimal dispersant type and concentration ratio of abrasive to dispersant were determined, and the effect of the selected dispersant on jet polishing performance was validated. The results of the dispersion stability experiment indicated that, in comparison to Na(PO)\({}_{6}\) and polyethylene glycol (PEG), the polishing solution containing 1.0-2.0 wt% phosphoric ester compounds exhibited a more stable dispersion effect (zeta potential \(<-50\) mV) and superior dispersibility, characterized by a smaller average particle size. Furthermore, K9 optical glass was subjected to fixed-point and local polishing using phosphoric ester compounds as the dispersant. The fixed-point polishing experiment revealed that, at a dispersant concentration of 1.0 wt% and an abrasive concentration of 20 wt%, a smooth and symmetrical material removal profile could be achieved. In the local polishing experiment, the reduction rate of the root mean square of the surface roughness (RMS) increased from 54.33% to 82.24%, and the reduction rate of peak-to-valley height difference in surface (PV) increased from 38.84% to 68.97%. In conclusion, the incorporation of a dispersant proves effective in enhancing the dispersion stability of the polishing solution and dispersibility of the abrasive particles, thereby improving the surface quality of the materials in MAWJP. micro-abrasive water jet polishing polishing; polishing; dispersant; dispersion stability; polishing solution; surface quality +
Footnote †: journal: Applied Sciences  
as a non-contact polishing process, MAWJP avoids tool wear and thermal stress on the workpiece surface during polishing, rendering it apt for processing and polishing micro, complex-shaped workpiece surfaces [5]. This technology has found broad applications and has been extensively employed in the finishing of optical components and microgrooves [6]. [PERSON] et al. [7] were pioneers in suggesting the application of abrasive jet technology for polishing BK7 glass. Their experimental outcomes demonstrated a decrease in the root mean square of the surface roughness (RMS) value after polishing, from 350 nm to 24 nm, while preserving a surface roughness of 1.6 nm. This substantiates the viability of employing abrasive water jet technology for optical surface polishing and shape modification. Subsequently, abrasive water jet polishing technology has garnered significant attention from a diverse group of scholars. [PERSON] et al. [8] optimized the removal profile derived from experiments and utilized it for polishing BK7 glass. The experimental outcomes demonstrated a decrease in the peak-to-valley height difference in the surface (PV) from 1.492\(\lambda\) to 0.294\(\lambda\) (\(\lambda\) = 632.8 nm), and in the RMS from 0.166\(\lambda\) to 0.029\(\lambda\). [PERSON] et al. [9] conducted a study involving fluid jet polishing on fused silica glass with a diameter of 120 mm and a thickness of 20 mm. The study explored the effects of abrasive slurry and incidence distance on polishing accuracy. The experimental outcomes indicated a reduction in the PV of the polished workpieces from 0.178\(\lambda\) to 0.046\(\lambda\), and the RMS decreased from 1/25\(\lambda\) to 0.007\(\lambda\). This suggests a substantial enhancement in the surface accuracy of the workpieces' materials due to fluid jet polishing. [PERSON] et al.