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Nowadays, the environmental concern in machining industry is a fact. Because of that, in this article a new cooling-lubrication system which combines CO2 cryogenic and MQL technologies is presented. The aim of this new cooling-lubrication system is to offer an ecological and economic efficient alternative. Two nozzle adapters are proposed with different CO2 outlets. The developed nozzles are Plug & Play and directly applicable to commercial MQL systems. The behaviors of nozzle adapters were simulated by CFD (Computational Fluid Dynamics) and the optimal nozzle adapter was tested by milling Inconel 718 ®. In these milling tests, the tool life was measured and using different main cooling-lubrication techniques: dry, wet, CO2 stand alone, MQL stand alone and CO2+MQL (proposed alternative).

Ball burnishing has proved to be a highly effective mechanical finishing process of industrial workpieces, because of the excellent surface roughness and fatigue performance that induces in treated workpieces. In order to obtain specific target results from this complex plastic deformation process, its parameters must be accurately controlled. This paper focuses on the influence of the lateral pass width on the average surface roughness of aluminum 2007. Two values of lateral pass width are tested, with two control variables: number of burnishing passes and applied burnishing force. Furthermore, the ball burnishing operation is performed with two different tools: a conventional non-assisted ball-burnishing tool, and a vibrations-assisted one. The most suitable lateral pass width proves to be the distance between the highest peak and lowest vale of the P-profile of the burnishing path, and significantly better results are obtained by assisting the process with vibrations. At the end of the paper, values for lateral pass width for each group of operation conditions are recommended.

This article reports on a novel machining process technique: in situ electrically assisted turning process based on the influence of electropulsing. An in house generator was used to induce a current intensity of 90 A, a pulse duration between 50 and 200 µs and frequencies between 100 and 300 Hz. The influence of different electropulsing configurations assisting the machining process was studied, specifically on the surface properties and the power consumption in 1045 steel. The results show that the electrically-assisted turning process improves material machinability, decreasing the power consumption up to 104 W and the specific cutting energy up to 22%. The assisted process also modifies the surface properties, the average surface roughness decreases within the range of 7 to 22% when compared to the conventional turning process.