Fig. 1. Photographs of (a)-(c) light-transmitting and (d) light-absorbing PC specimens

Fig. 2. PC specimens with different surface roughness. (a) No.1; (b) No.2; (c) No.3; (d) No.4; (e) No.5; (f) No.6

Fig. 3. Breaking force of laser welded specimen versus surface roughness of light-absorbing specimen

Fig. 4. Weld width of laser welded specimen versus surface roughness of light-absorbing specimen

Fig. 5. Fracture morphologies of laser welded specimen magnified by (a) 20 and (b) 100 times when light-absorbing specimen surface roughness is 1.600 μm

Fig. 6. Fracture morphologies of laser welded specimen magnified by (a) 20, (b) 50 and (c) 100 times when light-absorbing specimen surface roughness is 0.218 μm

Fig. 7. Absorptivity of light-absorbing specimen versus surface roughness

Fig. 8. Surface profile curves of 6 light-absorbing specimens in Fig.2. (a) No.1; (b) No.2; (c) No.3; (d) No.4; (e) No.5; (f) No.6

Fig. 9. Two rough surface models generated by W-M function. (a) Ra=1.600 μm; (b) Ra=0.218 μm

Fig. 10. (a) Simulated three-dimensional surface and (b) its local amplification of 100 times when Ra=1.600 μm and Ds=2.3572

Fig. 11. Combination of Gaussian surface heat source and rotary-Gaussian body heat source

Fig. 12. Central node temperatures of specimens with different surface roughness versus time

Fig. 13. Laser reflection from rough surfaces

Fig. 14. Reflected light energy distributions for different surface roughness. (a) Low surface roughness; (b) high surface roughness

Fig. 15. Weld temperature of specimens with different surface roughness versus time