Study on the corrosion resistance of 316L stainless steel by picosecond laser cleaning

To study the influence of different cleaning methods on the corrosion resistance of 316L stainless steel surface, this paper carried out polarisation curves and electrochemical impedance spectroscopy studied on the uncleaned, acid pickling cleaning, and picosecond laser cleaning samples. The surface morphology of the samples after electrochemical testing was detected by laser confocal microscopy and scanning electron microscopy, and then the electrochemical corrosion behaviour of the samples in 3.5% NaCl solution was analysed under different cleaning methods. The results show that compared with the uncleaned sample, the corrosion potential of the sample after picosecond laser cleaning was relatively improved. At this time, the corrosion current density was as low as 2.29 × 10 –6 A/cm 2 , the polarisation resistance value was as high as 18615 Ω·cm 2 , the impedance modulus was as high as 5.5 × 10 5 Ω, and the capacitance-impedance radius reached the maximum value. In conclusion, the corrosion resistance of the sample after picosecond laser cleaning was better.