Fig. 1. Surface morphology of sample and schematic of laser-polishing setup. (a) Surface cut by wire electrical discharge machining; (b) schematic of experimental equipment

Fig. 2. Pictures of polished surface in different pulse duration values and pulse energy forms photographed by stereo microscope

Fig. 3. Evolution of surface morphologies in different pulse duration values. (a) 10 ns; (b) 50 ns; (c) 150 ns; (d) 250 ns; (e) 350 ns; (f) 400 ns

Fig. 4. Scribing positions and profiles of polished surface in different pulse duration values. (a) 10 ns; (b) 50 ns; (c) 150 ns; (d) 250 ns; (e) 350 ns; (f) 400 ns; (g) profiles

Fig. 5. Morphologies of polished surface at different pulse energy value and spot overlap rates. (a)Initial morphology; (b) pulse energy of 1.5 mJ, spot overlap rate of 78%; (c) pulse energy of 1.0 mJ, spot overlap rate of 86%; (d) pulse energy of 0.5 mJ, spot overlap rate of 93%; (e) pulse energy of 0.1 mJ, spot overlap rate of 99%

Fig. 6. Scribing positions and profiles of polished surface at different pulse energy values and spot overlap rates. (a) Pulse energy of 1.5 mJ, spot overlap rate of 78%; (b) pulse energy of 1.0 mJ, spot overlap rate of 86%; (c) pulse energy of 0.5 mJ, spot overlap rate of 93%; (d) pulse energy of 0.1 mJ, spot overlap rate of 99%; (e) profiles

Fig. 7. Variations of surface roughness R_a at different pulse duration and pulse energy forms. (a) Variation of surface roughness with pulse duration;(b) variation of surface roughness with pulse energy and spot overlap rate

Fig. 8. Effects of high energy dispersion pulse laser on micro peak and valley of high roughness surface. (a) Three-dimensional surface morphology; (b) profiles of surface scribing

Fig. 9. Effect of low energy concentration pulse laser on micro peak and valley of high roughness surface. (a) Three-dimensional surface morphology; (b) profiles of surface scribing