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In evaluating larger number of measurement data, it is proper to analyze them statistically. It is important to determine the effect of measured data number on the experiment results. This paper is focused on the determination of the effect of the basic file size (data obtained in the experiment) on the final measurement results. In milling the cutting inserts of sintered carbide (SC) were used. The same cutting conditions (depth of cut, feed, cutting speed) and were used. The cutting inserts wear was measured after the same cutting time. At the beginning of experiment 120 measured data (edges) were used. Number of measured data was gradually increased (to 240, 360, 480, 600, 720, 840, 960 and 1080). Totally 9 basic files was obtained. In the conclusion of the paper lists of all results are presented together, with their mutual comparison and prediction of the possible development of tool wear at higher number of cutting edges.

In 1906 Taylor mathematically defined the dependance of tool durability on cutting speed in the form: T=CT/vm for the first time. It is an equation of a hyperbola, which represents itself as a straight line in double logarithmic net according to Taylor. The dependance is valid for the tools made of high-speed steel. It has still been used in spite of the fact that new cutting materials, which cannot be used according to it, or can be used only partially in a narrow range of higher cutting speeds. The course of function T=f(vc) for the tools made of sintered carbid and ceramics will be identified in the paper. It requires extensive durability tests in a wide range of cutting speed. Interesting conclusions can be derived from its course.

Kaizen strategy is the most important Japanese management concept. Supporters of this by all means an interesting management philosophy consider it as a basis for achieving success by the company. The analyzed company X Stainless motivated by others companies market successes decided to deepen the knowledge of the Kaizen philosophy, which resulted in the implementation of this method of management in its ranks. The essence of Kaizen is to change ways of thinking and way of production management. Underlying this theory, there is the gradual but constant improvement of the status quo with the active involvement of every management employee and the rest of the company workers. Kaizen educates employees towards finding ways to better perform their duties. Performance of work is closely connected with the observance of standards and the introduction of small improvements in order to continue its improvement.

This paper outlines the hard machining procedures, their applicability, the increase of their efficiency and the possibilities provided through their combination. It focuses on the advantages of the cutting and grinding compared to each other and also on the cases when it is appropriate to apply them or possibly combine them.

Problems about hardened steels grinding is presently very important part of engineering. Many applications of these materials using in practice, machine, devices and in different industry like automotive, aviation, cosmonautics and in area of health, safety and protection of passengers in vehicles, planes, aircrafts, ships, trains and many others. Because of these areas that used the passengers is very important surface quality and durability of these parts of machines. Topic of surface quality changes in working of the parts is especially important in dynamic load parts. These parts are very loaded by alternating stress in cases of double axis stress (torsion and bend). Such materials are for example bearing, shafts and gears. In all cases the production technology influences surface quality.

Using recycled aluminium cast alloys is profitable in many aspects. Secondary aluminium produced from recycled metal requires only 2.8 kWh/kg of metal produced and creates only about 5 % as much CO2 as by primary production. Improved mechanical properties of recycled (secondary) hypoeutectic Al-Si cast alloys are strongly dependent upon the distribution and the shape of the silicon particles; the morphology, type and distribution of the second phases, which are in turn a function of alloy composition and cooling rate. The presence of additional elements as Mg, Mn, Fe, or Cu allows many complex intermetallic phases to form, which make characterisation non-trivial. They are added deliberately to improve and to provide special material properties. Controlling the microstructure is, therefore, very important. A combination of different analytical techniques (light microscopy upon black-white etching; scanning electron microscopy (SEM) upon deep etching and energy dispersive X-ray analysis (EDX); quantitative phase analyse upon Image analyzer NIS Elements 3.0) were therefore been used for the quality control of microstructure in recycled AlSi9Cu3 cast alloy.

This paper deals with application of Barkhausen noise for analysis of surface integrity in turning and grinding operation. The stress state is analyzed in relation to tool wear. The results of measurements show that the residual stresses are not homogenous on the machined surface. This homogeneity depends on tool wear and stability of cutting process. Application of non-destructive testing through the Barkhausen noise is more suitable for grinding operations. Application of Barkhausen noise testing for turning operation will require the next research.

Nonconformities identified in anti-corrosion coating process on the steel constructions were analyzed in the article. Analysis of these nonconformities allows for process improvement by finding new ways of process leading.

The aim of this paper is to show the applicability of the Laser Scanning Confocal Microscopy (LSCM) for the fractographical research of the compact tension specimens. Scanning Electron Microscopy (SEM) together with Light microscopy (LM) are prevailing techniques for the fracture surfaces examination [1,2]. Information about the surface topography obtained by LM and SEM is reflected in 2D image whereas LSCM provides 3D images. In this work the fracture surfaces of the compact tension specimen were examined by LSCM and by SEM and the main features as cleavage facets, ductile dimples, stretch zone and fatigue were observed.

Computer tomography could be used for non-destructive inspection of castings. This contribution deals with application of computer tomography for determination of inner quality of high-pressure die casting parts, especially in relation to leakage and compared with other testing methods. In praxis, the leakage location is identified by fracture test or by metallographic observation. Often the oxides and porosity are found. Porosity is also often found out after machining operations. This work proposes non-destructive methods of castings inspection, especially tomography, in comparison of other known and available methods, with the goal to find out the problem before machining with minimal losses.

Quality product is dependent on reliable and serviceable manufacturing facility, which is influenced by effective and timely performed maintenance, including checking and refilling of lubricants and other vital fluids. For assessing the state of lubricants and parts of manufacturing machinery, it is possible to use a series of analysis including, for example particle counter and particle shape classifier LaserNet Fines-C, flash point, kinematic viscosity, water content, determination of solid particles, wear metals, etc. Each analysis used to assess technical condition of lubricating oil and machine and helps to carry out maintenance at appropriate intervals, which are directly affected by the technical condition. Such maintenance system achieves economic savings over the maintenance performed in a tightly planed and schedule. The paper compares examples of oil analyses of two compressors.

The X-Ray Photoelectron Spectroscopy is versatile technique based on high energy photon stimulation. The investigated areas of the sample are about the top 10 nm. The basic composition and chemical bonds can be evaluated. The XPS can be used in the quality control, ageing studies and many more. Samples of CoSbY alloy, carbon-rich coatings and films with tin were investigated here.. The importance of proper handle on carbon contaminations on CoSbY alloy is illustrated. The chemical shift of carbon C 1s peak and oxidation state tin Sn 3d photo electron peaks are presented.

This paper deals with grinding of the automotive parts and surface quality after grinding. This paper describes results from the experiment with grinding of materials EN ISO 100Cr6 and EN ISO C55E used in automotive industry like materials of the machine parts. This experiment shows possibilities with grinding of this materials and the influence of the ground process parameters during grinding e.g. normal and tangential force, cutting fluids and feed. Together with this experiment is evaluated also the surface quality of machined parts. The evaluated parameters of surface quality were choice roughness and geometrical accuracy - roundness.

This paper deals with problems about the wood requires orthogonal cutting and its history and presents development.

Nowadays every reliable activity simplification leading to time saving is an important positive. The constraint of customers to documentation of mechanical properties just on castings is everlasting. It can be achieved without submission of casting to destructive testing, by non-destructive structuroscopy. This contribution describes the possibility of non-destructive determination of ultimate tensile strength of castings of graphite cast irons using TELIT structuroscope and parametrization of mathematical model for non-destructively determined strength using this instrument.

In this paper the surface finish produced by turning of perlitic-ferritic nodular cast iron (NCI) with multilayer (TiC/Ti(C,N)/Al203/TiN) coated P20 carbide and nitride ceramic cutting tools is characterized using both 2D and 3D roughness parameters. The surface finish was characterized using a set of surface roughness parameters including vertical (Ra, Rz, Rt), horizontal (RSm), hybrid (R∆q), and additionally statistical (RSk, RKu) and functional parameters based on the bearing curve (Rmr(c) Rpk, Rvk, Rk). Some 3D roughness parameters were also considered and compared with 2D parameters. The data obtained can support the optimization of finishing operations of NCI parts.

One of the most important problems in broaching technology is wedge wear one. The main trouble is to establish proper criterion of admissible wedge wear. Theoretical analysis of the loading of cutting wedge during broaching has been presented. Subsequent phases of broach wedges wear have been shown, on the base of authors' own investigations. The research has brought the authors to the conclusion that broach wear should be determined by other indicator thanks to which the state of the process can be easily and quickly defined. Such an indication is the condition of the surface layer being machined.