RESEARCH AND INNOVATION An emerging alternative to conventional micromachining processes BIOMACHINING: The sustainable biotechnology that makes a difference > J.R. Otegi, Department of Graphic Design and Engineering Projects. Faculty of Engineering of Bilbao > N. Rojo, E. Díaz-Tena & G. Gallastegui, Department of Chemical and Environmental Engineering. University College of Engineering of Vitoria- Gasteiz; > A. Elías & A. Barona (astrid.barona@ehu.eus), Department of Chemical and Environmental Engineering. Faculty of Engineering of Bilbao What is biomachining? In response to the soaring global demand for micro-compo- nents, micromachining technology is in constant growth. Biomachining or bioet- ching is an emerging alternative to con- ventional micromachining processes. Based on recent advances in biotechnology, biomachining is now a controlled chemical-microbiological process for selec- tively forming microstructures on a workpiece through metal removal or dissolution (Diaz-Tena et al., 2017). The bacteria are responsible for the in-situ recovery (restoration) of the oxidant agent, conducting an ongoing process that depends solely on microbial activity (Figure 1). What are the advantages of biomachining? Biomachining involves machining micro-components with minimum stress, and without applying a cutting force during the process. Furthermore, it ensures precision and high quality, without distorting or damaging the workpiece. The microbial activity produces little heat and residual stress, with the material being removed slowly and uni- formly. The electrolyte is endlessly recycled, reducing the overall cost. Longer machining times are offset by batch production and cost reduc- tion (Diaz-Tena et al., 2016). 12<<