In the paper, the concept of an electrochemically assisted microturning process is presented. This is a hybrid machining process in which microcutting directly removes the material while electrochemical passivation changes the conditions of material removal. A test stand was designed and built to investigate this process. The experimental part includes a discussion of the research methodology and a comparison of the straight turning results in the case of machining 1.4301 stainless steel without and with electrochemical assistance. The change of the main cutting force resulting from electrochemical assistance was selected as the main investigated technological factor. Based on this study, we can state that in the case analyzed here (when only passivation is taken into account), electrochemical assistance brings significant benefits when the depth-of-cut is ≤1 μm.

The paper investigated an electrochemically-assisted microturning process. Depending on the variant of electrochemical assistance, material can be removed with simultaneous electrochemical and mechanical action or electrochemical assistance can change the conditions of the cutting by changing the mechanical properties of the machined material. The experimental part includes discussion of the study methodology and a comparison of straight turning results in the case of machining 1.4301 stainless steel with and without electrochemical assistance. Based on this study, we can confirm that electrochemical assistance brings significant benefits in both variants, especially when the depth-of-cut is in the range of 1 µm.

Precision milling of free (curved) surfaces with the use of monolithic milling cutters is used in the production of hardened steel elements such as dies, molds, or press tools. Precision milling processes are carried out with the following milling parameters: axial cutting depth ap <0.3 mm, cutting width ae <0.5 mm and the required machining accuracy below 40 mu m. The quality of the obtained surfaces in injection molds is directly transferred to the quality of the molded part. One of the key criteria for the manufactured elements is the surface quality which is mainly assessed by the roughness parameters. Due to the use of carbide tools high reliability and quality of machining is obtained which allows to eliminate the grinding process. In precision milling processes, due to the very small radius of the cutting edge and the cross-sections of the cutting layers, the conditions that must be met for the decohesion process to occur are fundamentally different from macro-scale. The minimum value range of ap and ae parameters was determined in a carried-out experiment, which allows for stable and repeatable machining. The tests were carried out with double-edge shank cutters with a diameter of 6 mm on a workpiece made out of WCVL hardened steel 45-47 HRC. Recommended machining conditions have been deft ned to ensure the required technological quality of the surface layer. The research was fi nanced under the research project POIR.01.01.01-00-0890/17 co-fi nanced by the European Union from the European Regional Development Fund.

In the paper the concept of electrochemically assisted microturning process was presented. This is a hybrid machining process in which the microcutting directly removes the material while the electrochemical passivation process is changing the conditions of cutting. The experimental part consist of description of passive layer formation process on 304 steel samples and results discussion of passive layer thickness and mechanical properties measurement with ellipsometry and nanoindentation technique.