The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Superficial three dimensional material forming based on flat virtual image (picture) luminance is a new, original application of high-pressure abrasive-water jet forming. In article are described basis of three-dimensional forming of ceramic and rock materials by using scanning method of high-pressure abrasive-water jet in conjunction with deep and jet velocity parameters. It was built a control system...
Summary The paper presents the results of investigations on the dynamic strength of vitreous bond grinding wheels made of microcrystalline alumina type sol-gel subject to a bursting test. A developed statistical model, giving consideration to the effect of abrasive-grain size, structure, hardness and concentration of microcrystalline sintered alumina SC in the binder material of these tools, has been...
Self-excited chatter is one of the most undesirable phenomena in modem machining. The effects of the chatter are: poor quality of the machined surface, increased noise emission during the working, more rapid wear of cutting tools, and decreased service life of the machine tool itself. To remedy the problem, vibration absorbers are used among others in practice. In the paper a Model Predictive Control...
The effective managing of the processes is grounded on taking the decision based on facts - values of assumed criteria. The paper includes an analysis of the qualitative process capability coefficients cp, and cpk which can be used as criteria for validation of manufacturing processes. Possible applications of vibroacoustic methods to the validation of the manufacturing processes for ceramic grinding...
In the paper author described results of geometric structure identification of grinding wheel cutting surface (GWCS) for different wheel characteristics. Dressing parameters and several grinding processes were analyzed. For evaluation of GWCS micro-geometry and analysis of normal distribution of profiles, achieved from surface analyzer, was applied. The results of the analysis are also under discussion...
Results of investigations and assessment of usability for abrasive tool of new type for applications in finishing operations of holes including electrochemical machining have been presented in the paper. Minimization of unit pressures which normally limits machining productivity was compensated by additional dissolution due to electrochemical machining. Efficiency of this process is satisfactory because...
Significance and application range for grinding wheels made of ultra-hard materials is on steady increase. It stems from introducing new materials, imposing higher requirements on advanced products and developments in manufacturing automation. The diamond tools are used more and more widely in industries and their share in abrasive machining approaches 20%. The standard methods of their sharpening...
Results of hybrid machining AEDG, Abrasive Electro Discharge Grinding, where grinding is assisted by electric discharges, have been described in this paper. The experiments have been conducted on the electro-discharge machine tool FORM-2LC ZNC which was additionally equipped with the grinder of pneumatic drive and the grinding wheel made of metal bonded cubic boron nitride (CBN) as an electrode. Quantitative...
This paper presents a new generation of zonal diversified structure grinding wheels with micro-crystalline aluminum oxide grains (SG) and glass-crystalline bond. New grinding wheels were examined in a single-pass internal cylindrical grinding process. An influence of the grinding wheel peripheral speed vs, the workpiece peripheral speed vw, the working engagement ae and the axial table feed speed...
The method for estimation of free-form surface accuracy is described in the paper. The surfaces were scanned by coordinate measuring machine and it implicates the fact that the surfaces are described by irregular nets of nodes and the measuring result requires the correction of the probe radius. The presented method is bases on the comparison of two sets of points which are described by irregular...
The paper presents the problem of the influence of the structure of oxide layers obtained in an electrolytic process on tribological cooperation with constructional materials. Microhardness and abrasion resistance of oxide layers obtained on aluminium alloys by means of hard anodizing depend mainly on their porosity, morphology, surface roughness and layers' thickness. Utilitarian properties of alumina...
The paper presents results of trade-off studies on the effectiveness of internal cylindrical grinding by the use of grinding wheels made of microcrystalline aluminiumoxid type SC and conventional abrasive material type 99A.
The article presents the results of the research on the influence of the cutting speed vc and feed fon the surface roughness in the course of finishing turning of the graphite carbon sealing with the polycrystalline diamond edge. The following mathematical models of relations were received: Ra = g(vc, f), Rp = g(vc, r), in order to establish optimal machining parameters concerning the surface roughness.
The process of surface roughness formation is complex and dependent on numerous factors. The analysis of the latest reports on the subject shows that mathematical relationships used for determining surface irregularities after turning and milling are not complete or accurate enough and, therefore, need to be corrected. A new generalized mathematical model of roughness formation was developed for surfaces...
In this paper there have been wavelet methods introduced in the application for a machined surface image analysis. Digital image of a machined surface was analysed with the use of Digital Wavelet Transform (Coiflet). The statistical description of particular wavelet decomposition levels made possible the estimation of surface roughness parameters with the use of a neural network.
The method of choosing the best place for mounting acceleration pick-ups for monitoring self-excited vibration, which often develops in the machine tool - cutting process system, is presented. The criteria for the choice of a single sensor placement and its orientation are the following: the larger possible value of measured signals at each chatter frequency and similarity of magnitudes of these signals...
Despite many studies on the methods of calculating stress in an adhesive bonded lap joint using the finite element method (FEM), significant discrepancies between recommendations of various authors were noted as for the selection of the number of layers and the kind of finite elements along the thickness of the joint. These discrepancies were also noticed while making assumptions that could simplify...
The results of cutting process study when turning E235 steel by solid carbide P25 TiN-coated inserts are presented in the paper. The dry turning and minimal quantity cooling lubricant (MQCL) turning were compared. It was observed, that area of shot spiral chip and lamellar chip forming is wider when MQCL turning in comparison with dry turning. The ribbon chip is formed only when large pressure air...
The article presents the kriging methods for interpolation of the spatial irregular net of nodes. The simple and ordinary kriging have been described. The variogram, which is a part of ordinary kriging has been explained. The worked out extension of ordinary kriging for the cylindrical coordinates and the applications of kriging method for the reverse engineering have been shown.
The paper presents the possibilities of regular surface texture generation by plunge grinding with the wheel prepared in a special way. The simple variant of the method consists plunge grinding with the wheel having helical grooves obtained by single point diamond dressing. Three basic types of surface may by shaped as the effect of specific wheel surface reproduction. Geometrical characteristics...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.