Fig. 1. Experimental schematic of (a) LSPP and (b) one-on-one damage test.

Fig. 2. The one-on-one damage probabilities of coatings without and with LSPP at overlapping rates of (a) 30% and (b) 50%.

Fig. 3. XRD patterns of coatings with LSPP at overlapping rate of (a) 30% and (b) 50%, with (c) and (d) showing the corresponding specific XRD patterns of the (020) peak.

Fig. 4. Statistical chart of the microstress and LIDT.

Fig. 5. The two typical damage morphologies of coatings with LSPP processed by an energy of 0.6 J at overlapping rate of 30% tested by SEM at (a) 31.8 J/cm² and (e) 74.9 J/cm², respectively. SEM and FIB images of the central pits of coatings: (b) and (f) without LSPP damaged at 74.1 J/cm²; (c) and (g) with LSPP processed by energy of 0.6 J at overlapping rate of 30%, and damaged at 74.9 J/cm²; (d) and (h) with LSPP processed by energy of 0.2 J at overlapping rate of 50%, and damaged at 76.5 J/cm².

Fig. 6. Size distribution of plasma scalds versus laser fluence of coatings: (a) without LSPP; (b)–(d) processed at an overlapping rate of 30%; (e)–(g) processed at an overlapping rate of 50%.

Fig. 7. The one-on-one damage probabilities of the 1064 nm HR coatings with or without LSPP under the different numbers of scans (a) at an overlapping rate of 30% and laser energy of 0.4 J and (b) at an overlapping rate of 50% and laser energy of 0.2 J.

Table 1. The minimum laser fluence inducing type I and type II damage morphologies for coatings without and with LSPP of different parameters.

Table 2. The total pressure of LSPP processes and the obtained LIDT with different overlapping rates and laser energies.