Visualization. 3. Effect of laser processing parameters on CA and SA, the error bars denote the maximums and minimums of the tested CA, the inserts represent the SA of samples with different scanning spacing.

For samples with laser scanning spacing of 30 μm, 40 μm, 50 μm, as the scanning times increase, the CA increase. When the times rise to 50, all samples possess excellent superhydrophobicity, the average CAs are 159.4°, 162.1°, 161.3° for scanning spacing of 30 μm, 40 μm and 50 μm, respectively. However, when the scanning times continue to increase, the CAs maintain constant almost, that is to say, the CAs reach the saturation value. For the samples with scanning spacing of 30 μm and 40 μm, when the scanning times are 50, the sample surfaces have ultralow adhesion simultaneously, the SAs are only 2° (the insert a and b). However, for the sample with scanning spacing of 50 μm, the drop is still motionless even if the sample surface is tilted by 10°. This high adhesion will impede the contraction of the contact line (CL). Hence, considering the processing efficiency and the sample performance, the parameter combination for preparing the LASH surface is a scanning spacing of 40 μm and a scanning times of 50.