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This paper deals with the assessment of the procedural gases progressive cooling methods and cooling by procedural liquids at turning technology on the final workpiece surface quality. Turning by using liquefied CO2, liquefied nitrogen and subcooled air supplied through the vortex tube was compared with the turning without process medium (taken as reference conditions) and with two procedural liquids EOPS 1030 and HOCUT 795 B. At evaluation effect of procedural gases there were monitored acting forces, cutting tool cooling rate and the machined layer of the material, cutting tool durability and cut surface quality which was characterized by surface roughness and dimensional accuracy. During the experimental part there were used devices as lathe SU50, piezoelectric dynamometer, the evaluation unit and profilometer. This issue was solved within solving the project TACR - TA03010492.

Titanium is widely used as biomaterial due to its excellent corrosion resistence, caused byTiO2 layer that is spontaneously formed on its surface, biocompatibility and good osseonitegration ability. To approach mechanical properties to human bone there is increase of using porous titanium. That form has lower density, causes better ingrowth of bone tissue which makes a strong bond between implant and bone. Porosity also decreases Young's modulus, which causes that the "stress shielding" is eliminated. New alloys based on titanium and silicon seems to be a perspective material for biomedical applications. This work is devoted to the optimization of the alloy composition and the addition of the pore-forming agent. It has been shown that this alloy can achieve the mechanical properties and microstructural features comparable with the human bone.

NiTi alloy exhibits the shape memory effect, which implies the application in medicine and also many industrial branches. This paper is devoted to the manufacture of these alloys by the use of powder metallurgy using reactive sintering. This method could enable easier production of this alloy and achievent of higher purity. However, for the optimization of this technology, the deeper knowledge of the mechanism of the process is needed. This work uses microscopy on real powder mixtures subjected to reactive sintering, as well as on model samples processed under various conditions.

This work deals with the problematics of 3D printing. Additive manufacturing (AM) covers a lot of principles of producing products and prototypes, for example, Direct Metal Laser Sintering (DMLS). This principle is based on sintering metal powder in thin layers, layer by layer. This theme is very extensive and a very popular research area. The paper is focused on printing thin walls. The material for printing was Maraging Steel MS1. This material achieves great mechanical properties like as high strength and high hardness. The tensile strength can be up to 2000 MPa after age hardening. The printer used was an EOS M290. The effects of different part position on safety of printing are compared. Also, the effect of support structures on accuracy was investigated. The main part of the paper is focused on an experiment where thin walls are printed and subsequently evaluated. The influences and limitations were investigated. The measurements were carried out on a Blickle Multicheck PC500 microscope.

An article deals with a concept of increasing efficiency of a current production process of bearing ring machining. A goal is to substitute a generally expensive technology of cutting when at least the same integrity of a surface is kept. A theoretical part is focused on a characteristic and analysis of a given component including an applied material 100Cr6 from which bearing rings are made. A practical part analyses and suggests an innovation of increasing efficiency of the machining process. Series of samples would be tested experimentally at university conditions (Workroom C2 of Dept. of Machining Technology, Faculty of Mechanical Engineering, Brno University of Technology) using CNC Lathe Machine SP 280 SY.
The article describes individual production workplaces along with used tool equipment that includes for the process of increasing efficiency the innovation in the form of the change of the production process, changes of most cutting tools and cutting conditions needed for the turning of heat-treated bearing rings. The article also deals with a surface integrity after turning of bearing rings. The integrity is analysed using a touch measuring tools (a manual roughness tester TS100, a tool with an inductive sensor Form Talysurf Intra) and using a touchless measuring tool Alicona Infinite Forces G4, including the measurement of a residual tension in a surface layer (Barkhausen noise) by the tool Rollscan 300.
The article finishes with a wear test of replaceable cutting blades at applied cutting conditions with a follow-up discussion, which describes problematic steps that were done in particular phases of experimental testing, and with necessary concept of further testing of bearing rings.

Cutting tool wear monitoring is one of key problems in automation of machining processes. Apart from the cutting tool wear monitoring for the cutting tool change and cutting tool failure, cutting tool wear monitoring may be one of the components for the adaptive control of a machining process. This paper is focused on the design of turning cutting tool wear sensors of the system flap - jet principal with increased extend. On the geometric principles in cutting with a turning cutting tool, the relations among the output of jet mouth, clearance angle and cutting tool wear were expressed. Two variants of turning cutting tool sensors were designed and experimentally verified. The results of experiments have proved the possibility to apply cutting tool wear sensor of the system flap - jet principal with increased extend in practical use.

Not only engineering production at present is characterized by increasing an international competition. It is achieved higher productivity with simultaneous improvement of quality parameters of machined parts by using of process fluids. In other words, the use of process fluids positively improves and increases the both the qualitative as well as quantitative parameters of the technological processes. Process liquids in machining occupy an important place and influence the outcome of the all processes. Choosing a suitable process fluid should be carefully considered. It is well known that, different machining technologies have different cutting conditions and thus completely different requirements on process fluids. Selection of a suitable process fluid is more important that the management of manufacturing companies admits. Unfortunately, the selection of suitable process fluids is very often underestimated.

This article is interested about drilling the holes to the alloy wheels. Tested were drills to drilling holes for screws and service holes. For screw holes was tested the three-stage drill with inserts from polycrystalline diamond. Drilled are two different diameters and the transition spherical or conical surface. The service holes were drilled with cemented carbide drill availible from Mapal labeled Mega-drill-Alu-180. During test, was modified the geometry of the drill and we watched what will be the effect of applied modification. Tested was seven variants of regrinding the drill. We evaluate the surface roughness, but also if the drill has the right position and not be pushed away from its axis. Finally was tested drill with three edges. This drill bit is from company Mapal labeled Tritan.

The paper deals with the lead-free soldering and influence of germanium amount in lead-free secondary solder Sn99. Lead-free soldering is an emerging area in the metallurgy of non-ferrous metals with a non-harmful effect on the environment. This method of soldering is very important for connecting materials in precision electrical engineering. In the experimental part of the paper are evaluated properties of lead-free solder Sn99 with graduated amount of Ge, compared with lead-free solder with the addition of nickel and silver. The goal was to provide knowledge on the impact of germanium on microstructure change, solderability and formation of oxides on the surface. From the results it can be concluded that germanium in lead-free solders reduces the formation of oxides on the surface by the addition of 0.01 wt. % Ge to the batch. With the amount of 0.01 wt. % also the grain is refined in the microstructure, resulting in improved castability. In terms of solderability experiments confirmed that germanium improves the flowability of solder on the PCB substrate.

The effect of microstructural banding (or so called segregation bands) on energy absorption capacity of dual-phase steels (DP steels) was examined by product of tensile strength and uniform elongation (TS×UE), as well as by Charpy V-notch impact test. A series of DP steels with different volume fractions of martensite (VFM) was prepared by intercritical annealing at temperatures ranging 740 to 840 °C. It was found that increasing of VFM has an inverse effect on values TS×UE and notch toughness. The results on samples with a notch and pre-cycled crack showed that presence of segregation bands influences capacity of steels to absorb the energy in initial stage as well as in stage of crack propagation.