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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.

The paper deals with the methodology and suitability of mathematical models applying analysis of the signal-to-noise (S/N) ratio as well as analysis of variance (ANOVA) and surface response methodology (RSM) on effect of TiAlN coating on chip ratio when drilling with HSS Co5 twist drill with diameter of 8 mm. Experimental work was performed according to design of experiment (DoE) Taguchi method. Cutting speed vc (m/min) and feed f (mm/rev) were selected as control factors in three levels and chip ratio K was used as a response variable. The main aim of this study is to establish relevant methodology for short term testing and find adequate mathematical model for chip ratio parameter K = f(vc, f) as a function of cutting condition when drilling with PVD coated and uncoated tool. Statistical software Minitab 14 was employed to process and evaluate of experimental data. The effect of feed and cutting speed on chip ratio was investigated through analysis of the signal-to-noise (S/N) ratio and analysis of variance. Equations for chip ratio K as a function of control factors were developed.

Article deals with design of appropriate artificial neural network for prediction of surface roughness as one of the very important indicators of machined surface quality. The drilling of nickel based super alloy UDIMET 720, was applied as test material. This type of material is most frequently used for jet engines components such as discs etc. Experimental data collected from tests were used as input parameters into neural network to identify the sensitivity among cutting conditions, tool wear and monitoring parameters and surface roughness. Selected parameters were used to design a suitable algorithm for control and monitoring of the drilling process with respect on surface roughness. The accuracy of predicted and measured values are compared and discussed.

Milling is one of the most universal operations in machining processes because it can remove the redundant part of material efficiently, and moreover, it can produce almost all kinds of contour surfaces with a high quality finish. Surface roughness plays an important role in determining the product quality since it strongly influences the performance of mechanical parts as well as production cost. Many types of cutting materials are used as tool materials in today's metalworking industry. Selecting the proper cutting tool material for a specific machining application can provide substantial advantages including increased productivity, improved quality and ultimately reduced costs. This article is aimed at determining the influence of different tool materials on surface roughness of AlMgSi aluminium alloy after side milling with using of the analysis of variance (ANOVA).

Al-Si alloys are leading casting alloys based on aluminum. Machining of aluminum alloys is currently frequently used and it is an important area of production. The paper deals with an experiment that was conducted at the Faculty of Production Technology and Management, University of Jan Evangelista Purkyně in Ústí nad Labem, where was machined alloy AlSi7Mg0,3. Samples were made for processing from the master alloy AlSi7Mg0,3, subsequently unmodified and modified of strontium Sr. This paper describes the evaluation of tool wear in terms of how or strontium modification may affect (reduce) the tool wear.

This paper reports on the outcomes of a study concerned with the mechanical properties of a new abrasive tool manufactured wholly from thermally treated recycled glass. These properties will aid in understanding the behaviour and performance of the treated glass. Mechanical properties were investigated using the most current and advanced nano-indentation methods. A computer controlled Nano Indentation hardness test (NHT) machine was used to obtain values of hardness and elastic modulus. The nano-indentation process was equipped as a FEM parametric model. The model was then processed by purposely developed numerical objective optimization algorithms in order to determine comprehensive material properties. The aim was to establish the optimal solution with reference to mean square root optimization criterion. The results show large elastic recovery upon unloading similar to a pure silica reference material and a surface roughness unique to this material which is entirely crystalline. The indentation mapping shows significant effect of heat treatment cycles on mechanical properties of recycled glass media.

This article deals with dry turning of nickel superalloy - Inconel 718. The different ceramic inserts were applied for cutting process. These inserts were produced by Greenleaf Corporation company. This paper discusses durability of cutting inserts, the different intensity of tool wear at various cutting parameters. The most suitable cutting conditions are chosen in the scope of applied tools.

During turning, in the course of the deformation of the material, a metallic deposit, a so-called built-up edge (BUE), may occasionally form, which may damage the surface and shorten the tool life. We have observed the effect thereof on chip formation using microscopic techniques and have developed a mathematical model for this process. Laboratory experience confirms the numeric solution of the time-delayed autonomous differential equations. This model can be applied to other technologies as well where the thickness of the undeformed chip varies.

Metallic charge heating before rolling process is very important stage of technological process of bars rolling in continuous rolling mills. Achieve of requires metallic charge temperature and permissible temperature difference on its length depends on metallic charge heating method and using of heating furnace. Main reason of form a big temperature differences on the metallic charge length in case of walking beam furnaces is disturbance their correctly work through seal wear between constant and moving elements of furnace hearth. The paper presents results of experimental investigation the non-uniform temperature distribution on the metallic charge length during round bars rolling. Thermovision monitoring were carried out during 70mm-diameter plain round bars rolling process in continuous shape mill D370 in one of industrial plant. Constructional steel S355J2G3 (according to DIN St 52-3) was used for the research. For the temperature measurement the ThermCAM SC640 thermovision camera was used.

The article deals with the automation of the grinding machine duty cycle. There are both described, the problems of the automation of the duty cycle and the present state summarised in this paper. The control systems of grinding cycle run from the experiences and process knowledge. Real GICS (Grinding Intelligent Control System) must be founded on the process monitoring and to create own control system with principal parameters of grinding. Cutting speed, workpiece motion speed, depth of cut, volume of coolant, course of cutting forces and other process parameters can form single control components at the adequate process knowledge. At some control systems description the authors assume the future possible direction of development, considering possibilities in the use of the expert and intelligent systems.

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.

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.