An application of a high power diode laser to remove oxides on AISI 316L stainless steel

An application of a continuous wave high power diode laser (cw HPDL) to the cleaning of stainless steel surfaces from metal oxides was studied. Firstly, the interaction between laser source and oxide layer onto the metal substrate was investigated using a combined SEM-EDS and XRD analysis. Secondly, the influence of operational laser parameters on overall cleaning performance was accurately analysed varying power, focus and interaction time. A statistical approach was employed to support the analysis of the laser cleaning process. Lastly, a technique for an 'in situ' measurement of overall cleaning performance, based upon the difference in gloss of laser treated and untreated zones, was defined and its reliability was checked by comparison with offline measurement techniques. On this basis, the experimental results demonstrated the suitability of a cw HPDL to the cleaning process of metal surfaces from oxides. The leading mechanisms of the cleaning process were also analysed.