Electrochemical micromachining (ECMM) of bulk metallic glasses

(Elektrochemische Mikrobearbeitung (ECMM) massiver metallischer Gläser)   

Electrochemical micromachining (ECMM) is an advanced technique for micro-shaping metallic materials surfaces with very high precision. A special ECMM method using metallic micro-tools and ultrashort voltage pulses is applied for micromachining Fe-based and Zr-based bulk metallic glasses. A key challenge is to overcome the strong passivity of those alloys and to properly exploit the high transpassive reactivity for controlled anodic dissolution at micrometer dimension. In particular for Fe-based glasses suitable processing parameters could be identified for the generation of micro-holes with high aspect ratio and of complex micro-shapes. The single-phase glassy nature is beneficial for achieving very high precision. The setup which was developed at the IFW is useful also for other microelectrochemical approaches, e.g. local potential probing etc.

S. Horn et al., Complex microshaping of bulk metallic glass surfaces by electrochemical means,
J. Mater. Res. 30 (2015) 3493-3501

R. Sueptitz et al., Electrochemical micromachining of passive electrodes,
Electrochimica Acta 109 (2013) 562-569

R. Sueptitz et al., Micro-patterning of Fe-based bulk metallic glass surfaces by pulsed electrochemical micro-machining (ECMM),
J. Mater. Res. 27 (2012) 3033-3040 J.

A. Koza at el., Electrochemical micromachining of a Zr-based bulk metallic glass using a micro-tool electrode technique,
Intermetallics 19 (2011) 437-444