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Machinabilty is a very important feature of materials subjected to machining process and can be analyzed from various aspects. The main question of many machinability studies is, ''What are the influencing factors on the machinability?'' This work describes experimental investigation on influence of cold flow forming process onto cutting force changes in machining of a 99.5% Al workpiece. the aim of the work is to find if and to what extend the cutting force is changed after plastic deformation in the process of cold flow forming. Full factorial plan has been applied in experimental works on three specimens, one before and two after plastic deformation. Cutting forces were measured by means of a three-component Kistler dynamometer Type 9265B. Regression analysis is performed in Microsoft Excel Data Analysis Package for both specimens. Obtained results have been compared and confirmed the fact that there are significant differences in character of the cutting force changes between undeformed and plastically deformed workpieces.

The paper presents one aspect of the analysis of energy consumption and productivity of the manufacturing operation. As an example of the operation, the operation of turning with a single-blade tool was taken. Sustainable development in its general concept implies sustainable materials, sustainable design, and sustainable manufacturing. This paper presents an analysis of one important part of sustainable manufacturing, and that is energy saving. The experimental study was conducted as follows. In laboratory conditions, an experimental-mathematical regression model of the relationship between cutting force and processing conditions was defined. Machining experiments were performed under ECO-friendly conditions with technology known as MQCL (Minimum Quantity Cooling Lubrication) machining. The obtained mathematical model was used to calculate the energy consumption and the workpiece material removal rate (MRR, productivity). The results of the analysis showed that there is a lot of space for optimization of machining conditions from the aspect of power consumption, with mandatory calculation and other machining costs, above all, the cost of tools and machine tools. In this regard, recommendations for analysis with the aim of power saving are given.

In the recent years, 3D printing has become a topic of great interest from both academic and the industrial sector through the increasing importance of Industry 4.0. This technology is based on layer-by-layer melting of materials to create a three-dimensional object. It is also known as additive production, and it is feasible through several different methods such as stereolithography, selective laser melting and sintering (SLM, SLS), these are just some of the examples, but fused decomposition modeling (FDM) has become the most interesting technique.This paper seeks to analyze the fracture strength (torque) of coupled gears made out of PLA plastic produced by the 3D printing process. To reduce the number of experimental measurements, the Taguchi L8(27) orthogonal array was used to analyze the influence of factors on two level. Investigated factors were: wall thickness, infill and number of infill lines, layer height, temperature, cooling and speed. Finally, optimization of most influential factors according to maximum torque was preformed, using Taguchi method too.