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The vibroburnishing is a process of surface plastic deforming applied to parts made of metallic materials to diminish the surface roughness, to increase the microhardness of the superficial layer, to generate internal stresses more convenient in certain service conditions of the parts. Practically, the ball vibrorolling process appeared as a result of including a vibratory motion. A ball is used as a deformation tool, as in the case of the more known process of burnishing. The analysis of the vibrorolling process showed that the simplest and the most accessible way of changing the process results could be based by considering the workpiece peripheral rotation speed and the longitudinal feed, respectively. An experimental research was proposed and performed to establish some empirical mathematical models that highlight the influence exerted by the workpiece peripheral rotation speed and by the longitudinal feed on the values of theRasurface roughness parameter and on the thickness of the hardened surface layer at the ball vibrorolling of the external cylindrical surfaces. The investigation considered also the influence of the distance from the test sample surface on the variation of the Vickers microhardness in the test sample superficial layer.

One of the machining methods able to ensure a high material removal rate in the case of obtaining threaded surfaces is the whirling machining. In order to obtain a high accuracy of the machined surface and low values of the surface irregularities, an adequate selection of the machining parameters is necessary. A geometrical analysis of generating the surfaces in case of applying the whirl threading was developed. Geometrical and kinematical conditions were considered and software was used in order to modelling the process and to highlight the influence exerted by some process input factors on the machining errors and height of the surface irregularities.

In the present study the authors propose an experimental framework in order to perform FEA analyses upon a 3D model of a connecting rod. The study presents some of the technical issues that have been overcome by choosing the right software tools and the differences in terms of results that they may produce, it shows the setup used in the analyses including its constraints and loads, the proposed algorithm that imposed the number of analyses as well as their type, and the way the analyses were conducted in order for the results to validate or invalidate a optimized model. Because the connecting rod's 3D model presents a high level of complexity in terms of the number of free forms surfaces contained within the geometry, the authors propose a procedure by which they divide the geometry in areas of interest and in doing so can determine the most critical and the most affected areas under a given load for each FEA analysis. This procedure allows a virtual perspective of the modality through which the considered part gets affected and behaves under a given load in terms of distribution of stress and deformation, results that are consistent with its overall behavior.

In the technical literature there are some studies which use measured signals in order to compensate the errors caused by vibrations [1, 2], by the cutting force [3], by the deflections of the technological system [4], and others. Also, the technical literature presents some studies [6, which give few measurement techniques in order to measure the error which appears into the turning process and also, some methods to compensate or eliminate the consequences produced by those errors. In such conditions, this study propose to establish a possible methodology that can make the measurement of the radial deviation which corresponds to a work piece obtained into a turning process. The novelty of this study comes from the method of measurement used and from the measurement stand which provide the values of the radial deflection for the processed work piece, during the process. The experimental procedure assumes the existence of an experimental stand which allows to measure the distance between a sensor and the considered work piece. In such conditions, the mathematical algorithms used will transform the received electrical signal into a physical displacement. The obtained results suggest that the signal provided by the experimental stand and which it is used for measure the distance between a sensor and the considered work piece, allows to establish, with accuracy, the values for the radial deviations of the work piece. Also, this fact can offer a graphical representation of the shape which corresponds to the real profile of the processed work piece.

The study aims to propose an alternative method of segmentation of digitized data. It begins by layering the item's surface. It analyzes the nodes inside a point cloud to detect any consistent shape change. If one detected, then it holds it and looks for the next one which may describe a possible shape change. The points between those two are classified and marked as part of the shape change curvature line. The method remembers the marked points and holds them as central nodes which will later form reference regions. It uses normal vectors behavior methods to detect shape changes along X and Y axis. As any other direction would not be detectable by the bi-dimensional approach it then introduces a morphological parameter capable on its own to fully describe the curvature variation of a given item's surface by means of Gauss's curvature. To evaluate curvature variation, the method proposes that the central node's curvature should be compared with every found limit points. Because of the noise present in any points cloud it establishes a threshold value beyond which points may describe accurately any shape change. This procedure takes place for all analyzed reference regions and collects only those who have a greater value than the threshold one. This considerations may be extrapolated to other types of geometries as well, as it is the case with cylinders or cones.