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.
Road surface microtexture (sub-millimeter scale) is essential for pavement skid-resistance. However, its measurement is only possible in the laboratory on cores taken from trafficked roads, and is time consuming. For efficient road monitoring, it is necessary to develop faster methods usable on-site.Collaboration has been developed for 2 years between LCPC and the laboratory Signal, Image and Communication...
The friction is of critical importance to sheet metal forming operations. It affects the flow of material in the tool and thereby the scrap rate and final quality of products. In the experimental work the frictional response was measured in a bending under tension (BUT) test under mixed lubricated conditions. The study includes stainless steel, but previous research on carbon steels, coated and uncoated,...
For the characterisation of a surface the spatial short wavelength cutoff of the measuring instrument is an important parameter that has to be known, especially when different techniques are to be compared. The definition of the transfer characteristic by a transmission bandwidth with λs and λc-limits as defined in the GPS-standards for surface contact stylus measurement is transferred here to the...
The high performance of industrial applications, requires increasingly technical functional surfaces, in particular from the point of view of topography and micro texture. To study the effect of abrasive finishing in a wide range of wavelengths of surface topography, we developed a multi-scale approach, based on the decomposition of surface topography by 2D continuous wavelet transform. This new approach...
Common functional requirements of work pieces are sliding, adhering, sealing and assembling. These requirements are asking for specific properties of surfaces. Surfaces of work pieces are described by geometrical properties such as dimension, orientation, form, waviness and roughness. Functional requirements need to be expressed by specifying these geometrical features. With the existing definitions...
According to most studies dealing with wear, abrasion can be considered on one hand as micro-cutting, leading to material removal (grinding), and on the other hand as micro-ploughing, leading to plastic deformation and lower material removal (abrasive wear). Understanding various flowing transitions around an abrasive particle, under well-established conditions, makes it possible to better control...
In our previous work, a new dual-tree complex wavelet transform (DT-CWT) model for surface analysis has been built, which solved the problem of the lack of shift-invariance that existed in the first and second generation wavelet models. Unfortunately, the DT-CWT model still has the same problem as the previous wavelet models in the lack of ability to detect line singularities or higher dimensional...
In most manufacturing of flat sheet and similar products, the tool-to-metal interaction performance does not simply relate to surface roughness parameters. For example, the frictional behaviour in rolling mills is not always related to the measured transverse roughness of the work rolls. The evolution of a surface during a rolling campaign changes both the transverse roughness as well as the rolling...
It is a well documented fact that in the developed world the general population is aging and the percentage of elderly persons within the total population is growing rapidly. This demographic change has massively increased healthcare demands. In aging persons osteo-arthritis has been shown to be particularly problematic. Osteo-arthritis is the progressive degeneration of the natural cartilage tissue...
In this paper various simulation methods of isotropic and anisotropic random surfaces of Gaussian ordinate distribution with Fast Fourier Transform are compared and the best of them are recommended. The method of numerical generation of arbitrarily oriented three-dimensional rough surfaces is presented. The procedure of digital simulation of two-process surface is introduced. An idea of the proposed...
The increasingly severe operating conditions of lubricated contacts cause a decrease of the ratio of lubricant film thickness to surface roughness. In order to avoid a reduction of their durability, laser surface texturing is a promising technology allowing to optimize the surface micro-topography. The present work studies the phenomena generated by the passage of a single micro-dimple in an EHL contact...
The development of user-friendly reference data sets (softgauges) and reference software algorithms for validating the software aspects of surface profile measuring instruments is described. A framework for the software measurement standards, and the form of the reference data (Type F1 softgauges) and reference software (Type F2) that were developed is discussed. This work was carried out as part...
The human skin is a material that exhibits complex behaviors. However, the determination of its mechanical characteristics is a paramount goal for dermatology (pathologies), and for the cosmetics industry (skin ageing). In this study, we propose a new method for the determination of mechanical characteristics of human skin in vivo. This identification is based on experimental results that are obtained...
Glancing angle deposition (GLAD) was used to sculpt chromium thin films sputter deposited by dc magnetron sputtering into the desired zigzag microstructure. The flux angle of incident species α was systematically varied from 0 to 50° and periodically changed from α to −α. The total film thickness was kept constant at 1μm and the number of periods ranged from 0.5 to 10. In order to improve the film...
Surface texture in general consists of microscopic surface roughness, waviness and form geometry. They can be discriminated by surface wavelength limits or cut-off values. Recently, 3D surface texture assessment has become popular even in the industrial world. This means that areal filtration is essentially needed and a robust authorized digital filter for 3D surface topography data is strongly required...
The visual aspect of rough surfaces such as steel surfaces becomes of great importance for the quality of the final product they are dedicated to. In a previous work, we have solved the theoretically complex problem of automatically classifying surfaces according to the quality of their aspect. In this case, the measurements were based on topographical maps obtained through interferometric microscopy...
Contour measurement requires the elimination of the radius of the tip. This process is sensitive to the noise in the measured data. Thus, the data of the trace of the centre of the tip has to be filtered. However, the Gaussian filtering is not the most appropriated for this purpose because it distorts the radius of small arcs in the profile and it is sensitive to spikes. The chosen morphological filter...
In this work, the tribological properties of tool coatings applied by physical vapour deposition are studied. A first aspect is the resistance to galling and abrasive wear, which are investigated by means of a flat/cylindrical multifrottement test. The observations for the evolution of the friction coefficient discriminate the various coatings as regards the onset of galling. In addition, topographic...
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.