Operando evaluation of passivation phenomenon during ECM/Laser-ECM: direct and on-machine evidence of passivation evolution

• DOI: 10.1038/s44334-025-00017-0
• Publication Date: 2025-03-05T07:19:42Z
• Authors: Muhammad Hazak Ar...; Krishna Kumar Saxena; Dominiek Reynaerts
• Keywords: Passivation

The performance of electrochemical micromachining (ECM) is compromised when processing highly passivating materials like Ti6Al4V, which can be improved through hybrid laser-ECM (LECM) facilitates passivation weakening. To date, phenomenon has been mostly analysed metallography and potentiometric techniques. Metallography provides oxide formation details over a limited observation area after machining, have relevance for manufacturing. Whereas, techniques cannot replicate ECM conditions to provide accurate transpassive regime conclusions. dynamic during requires an on-machine analysis technique production-oriented process history, thereby improving fundamental understanding at different conditions. Therefore, in this study we propose framework based on high frequency in-process current signals reflects the operando change evaluation phenomenon. We validated experiments, demonstrated that approach quantitatively capture behaviour sensitive microstructure same material. results showed weakening with increasing voltage up 30 V LECM. In addition, samples prepared by selective laser melting (SLM) were more resistant EC-dissolution compared rolled material porosity led inhomogeneous dissolution. since proposed both overall influence its it useful mechanistic studies potential further developed towards optimisation control.