| Sumario: | • This is the first detailed study of laser irradiation effects on zinc heritage objects. • Metallic zinc ablation threshold is lower than zinc corrosion ablation threshold. • There is no self-limiting effect during zinc laser cleaning. • Laser pulses from μs to fs initiates yellowing of zinc corrosion products. In this work lasers with pulse durations from μs to fs were used to clean zinc heritage objects from atmospheric corrosion deposits. Wavelengths at 355, 532, 800, 1064 nm were tested. The surface was studied by Raman spectroscopy, Scanning electron microscopy, X-ray diffraction and optical microscopy. It was shown that for all lasers used there is no self-limiting cleaning effect, and the metal melting threshold is lower than the corrosion complete removal threshold. A femtosecond laser produces the least surface melting with 100 fs pulse duration, the shortest in this study. Yellowing of corrosion layers due to temperature modification of zincite was observed with irradiation by all lasers used.
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