Localized corrosion of laser marked M340 martensitic stainless steel for biomedical applications studied by the scanning vibrating electrode technique under polarization

• Corrosion of laser marked (LM) martensitic M340 SS in 0.1 M NaCl studied using SVET.
• LM produces Cr-depleted regions due to selective volatilization and oxidation.
• LM causes active dissolution of M340 SS stainless steel.
• LM decreases Epit by 200 mV and Erepassivation by 250 mV.
• Formation of preferential cathodic sites are also associated to LM.

The corrosion of laser marked M340 martensitic stainless steel for biomedical applications was investigated using the scanning vibrating electrode technique (SVET) under simultaneous polarization and cyclic voltammetry in a 0.1 M NaCl solution. The laser marking greatly increases the active dissolution of the affected region and decreases the pitting potential due to Cr loss by volatilization and oxidation on the laser-melted zone. Laser marking also increases cathodic currents on the formed oxide resulting in a higher susceptibility to active dissolution and pitting corrosion.