Fig. 1. Schematics of laser micro polishing mechanism^[20]

Fig. 2. Laser micro polishing of micro-milled Ti6Al4V sample^[21]. (a) Comparison under different spatial frequencies; (b) surface morphology

Fig. 3. Surface over-melting mechanism^[33-34]. (a) Formation mechanism of surface periodic structure; (b) typical surface morphology

Fig. 4. Characteristics of ablation and vaporization mechanism^[36].(a) Schematic of ablation and vaporization mechanism; (b) morphology of typical laser polished surface

Fig. 5. Schematic of photochemical mechanism under ultraviolet laser polishing^[46]

Fig. 6. Continuous laser polishing ^[28,50]. (a)(b) Surface morphologies of Inconel 718 alloy; (c)(d) surface morphologies of SKD steel

Fig. 7. Structures of laser polished surfaces^[73]

Fig. 8. Nanosecond pulsed laser polishing of additive manufacturing TC4 workpiece^[47]. (a) Macroscopic image; (b) SEM image; (c) 3D topographic image

Fig. 9. Macroscopic image of AISI H11 steel after dual laser beam asynchronous combined polishing ^[85]

Fig. 10. Dual laser beam asynchronous combined polishing of additive manufacturing Inconel 718 alloy^[86]. (a) Macroscopic visual image; (b) comparison of 3D topographies of surfaces after nanosecond laser and dual laser beam combined polishing; (c) as-fabricated surface morphology; (d) surface morphology polished by nanosecond laser; (e) surface morphology after dual laser beam combined polishing; (f) as-fabricated surface 3D topography; (g) 3D topography of surface polished by nanosecond laser; (h) 3D topography of surface after dual laser beam combined polishing

Fig. 11. Laser assisted mechanical polishing^[90]. (a) Mechanism; (b) material removal rate after 120 min polishing

Fig. 12. Ultrasonic vibration-assisted laser polishing^[93-94]. (a) Experimental device; (b)(c) laser polished surface morphologies with different ultrasonic amplitudes

Fig. 13. Magnetic field-assisted laser polishing^[100]. (a) Experimental device; (b) sample and magnet location diagram; (c) simulation distribution of magnetic field; (d) influence of magnetic field intensity and laser power on surface roughness; (e) initial surface topography; (f) surface topography polished by laser without magnetic field assistance; (g) surface topography polished by magnetic field-assisted laser

Fig. 14. Microstructure analysis of 3D-printed TC4 alloy surface after laser polishing^[47]. (a) Inverse pole mapps; (b) phase distribution mapps; (c) nanoindentation load-displacement curves; (d) compression yield strength curves

Fig. 15. Typical applications of laser polishing technology^[101-103]. (a) 2Cr13 tool steel; (b) TA2 titanium impeller; (c) TC4 titanium ventricular assist device; (d) Inconel 718 fabricated by selective laser melting; (e) glass; (f) nylon PA12 fabricated by selective laser sintering

Fig. 16. Schematic of laser polishing machine^[52,110]

Fig. 17. Basic variants in laser polishing