Fig. 1. Schematic of experimental setup and processing principle for diamond picosecond laser machining

Fig. 2. Schematic of physics model and grid division

Fig. 3. Variation of temperature distribution with grid size. (a) Maximum temperature; (b) partial enlargement of Fig.3(a); (c) minimum temperature; (d) partial enlargement of Fig.3(c); (e) average temperature; (f) average temperatures under different model sizes

Fig. 4. Temperature distributions on diamond surface after irradiation of single-pulse picosecond lasers with different energy density values. (a) 5.96 J·cm^-2; (b) 6.96 J·cm^-2; (c) 7.95 J·cm^-2; (d) 9.94 J·cm^-2

Fig. 5. Temperature distributions along different paths under different energy densities for single pulses. (a) Temperature distribution along x axis; (b) partial enlargement of Fig.5(a); (c) temperature distribution along z axis; (d) partial enlargement of Fig.5(c)

Fig. 6. Influence of repetition frequency on diamond temperature under 10 pulses. (a) 100 kHz; (b) 1000 kHz

Fig. 7. Typical surface morphologies of microgrooves at different scanning numbers under laser power of 6 W. (a) 20; (b) 50; (c) 70; (d) 100

Fig. 8. Typical surface morphologies of microgrooves at different scanning speeds under power of 10 W and scanning number of 70

Fig. 9. Schematic of quality evaluation indicators for laser cutting of CVD diamond

Fig. 10. Defects at different positions within HAZ. (a1)(a2) Chipping; (b1)(b2) chipping and yellow modified zone; (c1)(c2) chipping and uneven edge

Fig. 11. Typical optical microscopic images of each sample

Fig. 12. Variance analysis of microgroove width. (a) Main effect diagram; (b)(c) interaction diagrams of various factors based on microgroove width

Fig. 13. Effect of scanning number on width of micro-groove. (a) Variation of micro-groove width with scanning number;

Fig. 14. Variance analysis of HAZ width. (a) Main effect diagram; (b)(c) interaction diagrams of various factors based on HAZ width

Fig. 15. Influence of scanning number on HAZ width