abrasive wear   

micro cutting caused by mating surfaces (two-body abrasive wear) or particles (three-body abrasive wear)




The process of picking out (abstracting) common features of objects and procedures to highlight the essential aspects []



accuracy of forming machines   

The accuracy can be divided into a geometrical accuracy that can meassured at a unloaded machine and a elastical flexibility than can be meaussred while the press is loaded.



active triangulation        

Triangulation with an active lightning device and a detector. The triangle consists of the light source, the test device and the detector.




In condensed matter physics and materials science, an amorphous or non-crystalline solid is a solid that lacks the long-range order characteristic of a crystal. [, 08.10.2015]




Anisotropy (in Material Science)is a material’s directional dependence of a physical property [, 08.10.2015]



bias voltage       

When a small bias voltage less than the work functions of the tip and sample is applied between these electrodes, electrons tunnel across this gap with a probability that increases exponentially as the tip approaches the sample. This provides an extremely sensitive way of detecting small changes in the surface height of a specific sample material due to the individual atoms and their clusters [A.P. Malshe et al. / CIRP Annals - Manufacturing Technology 59 (2010), 630]




Calibration is a comparison between measurements – one of known magnitude or correctness made or set with one device and another measurement made in as similar a way as possible with a second device.



CGAL (Computational Geometry Algorithms Library)      

access to efficient and reliable geometric algorithms in the form of a C++ library. []



chromatic abberation    

Chromatic abberation refers to the so called defects in coloring of different optics. They occur due to various wavelength in various focus levels by dispersion. Defects in colors can be prevented by the use of achromatic optics




Coating and Surface technologies on one hand improve existing materials and products; on the other hand they are indispensable for the realization of innovative products based on particular properties of thin films. Tailored coatings allow the adjustment of mechanical, chemical, electrical and optical properties of surfaces [K. Bewilogua et al. / CIRP Annals - Manufacturing Technology 58 (2009), 608]



coefficient of friction (COF)        

At lower cutting speed and higher feed rates the cutting forces are higher because of the higher coefficient of friction between the tool and the work material compared to higher speed and lower feed rates. [N.G. Patil et al. / Procedia CIRP 24 ( 2014 ), 88]



complex (graph theory)

is the higher dimensional analogy to a graph



Computational Geometry           

Computational geometry is a branch of computer science devoted to the study of algorithms which can be stated in terms of geometry. Typical problems that are solved with this method are Delaunay triangulations, Voronoi diagrams as well as convex envelopes



conceptual model           

A conceptual model is a model made of the composition of concepts, which are used to help people know, understand, or simulate a subject the model represents.



contact pressure             

see contact pressure



crystal symmetry, - system, -class, space group (phys.) 

Single crystals such as quartz, lithium niobate, lithium tantalite, and lead zirconate titanate (PZT) ceramics are widely used in industry. Development to obtain crystals with higher piezoelectric properties has been taking place. [Y. Namba, H. Takahashi / CIRP Annals - Manufacturing Technology 59 (2010), 589]




see figure




The empirical models obtained could be utilised to predict how the cutting parameters affect the grinding process and the machining quality of these non-traditional materials. The influence of shape, orientation and content of the reinforcement on material grindability is taken into consideration. [A. Di Ilio et al. / CIRP Annals - Manufacturing Technology 58 (2009), 291]



cutting force parameter

The resultant cutting forces in chatter stability can be described as: where Ktc is the cutting coefficient in the tangential direction; Kr is the ratio of radial to tangential cutting coefficients; Ks is the resultant cutting force coefficient; a is the depth of cut; and, h is the regenerative chip thickness, which is a function of the immersion angle, f. [S.S. Park, R. Rahnama / CIRP Annals - Manufacturing Technology 59 (2010), 392] (FORMEL EINFÜGEN CIRPA_1122)




The two-level decomposition was developed for performance analysis of manufacturing systems with non-linear flows including split/merge operations. [M. Colledani, T. Tolio / CIRP Annals - Manufacturing Technology 62 (2013), 449]



Deep drawing   

Deep drawing is a sheet metal forming process in which a sheet metal blank is radially drawn into a forming die by the mechanical action of a punch. It is thus a shape transformation process with material retention. The process is considered "deep" drawing when the depth of the drawn part exceeds its diameter.



degree of deformation / true strain       

The degree of deformation describes the quantity of the change of shape. The degree is positive when a section is stretched and negative when a section is compressed.




The Delaunay triangulation is a graph of a given (generator) point set that triangulates in a certain way that the greatest pointless circles are always the perimeters of triangles of the triangulation.



depth of field (optics)   

Geometric constraints include visibility, field of view, depth of field, and pixel resolution. The low difference in index of refraction between bead and ambient medium in optical trap assisted microsphere near-field nanostructuring also leads to severe spherical aberrations and therefore to an enhanced depth of field. [A. Weckenmann et al. / CIRP Annals - Manufacturing Technology 58 (2009), 706 & K.-H. Leitz et al. / CIRP Annals - Manufacturing Technology 61 (2012), 209]



design of experiments (DOE) (experimental design)      

In general usage, design of experiments (DOE) or experimental design is the design of any information-gathering exercises where variation is present, whether under the full control of the experimenter or not. However, in statistics, these terms are usually used for controlled experiments.



deviation of test sphere distance            

Deviation between the meassured value and the calibrated values of a distancen between two sphere centers



Digital (micro)Mirror Device (DMD)         

The displacement measurement device DMD, developed by Fischer, allows for measuring the displacement of the spindle relative to the housing. Attaching a special sensor into the tool flange enables detection of displacement within 1 mm accuracy. [E. Abele et al. / CIRP Annals - Manufacturing Technology 59 (2010), 796]



directed graph 

in graph theory, a directed graph is a graph, or set of nodes connected by edges, where the edges have a direction associated with them. [, 08.10.2015]



dlc layer system               

Diamond-like carbon coatings have an amorphous structure with variable fractions of sp²- and sp³-hybridized carbon atoms. The coating's structure, its properties and its behavior can be adapted by varying the parameters of the deposition process.



DLP, “Spatial Light Modulator“  

A digital mirror device is an electronically controllable field of moveable, micron sized and densely packed micromirrors defined with 2 addressable positions. It is used for high-resolution dynamic imaging in both the video projection and lithography as well as in the measurement technique for 3D topography measurement.



DoE (Design of Experiments)     

In general usage, design of experiments (DOE) or experimental design is the design of any information-gathering exercises where variation is present, whether under the full control of the experimenter or not. However, in statistics, these terms are usually used for controlled experiments.




see voronoi diagram



dynamic process forces

The major causes of geometric deviations of machined parts are e.g. an unintended varying material removal rate due to static and dynamic process forces and external forces [E. Brinksmeier, J. So¨lter / CIRP Annals - Manufacturing Technology 58 (2009), 507]




In physics, elasticity is the tendency of solid materials to return to their original shape after being deformed. Solid objects will deform when forces are applied on them. If the material is elastic, the object will return to its initial shape and size when these forces are removed. [, 08.10.2015]




Cutting is an extremely complex thermo-mechanical process that generates elastoplastic strains that exceed 1.0 at rates higher than 104 s 1. Most of the work required to cut a material is dissipated as heat, leading to rapid temperature changes from room temperature to near the melting temperature of the material (over 1000 8C in steels) within milliseconds. Heat is generated predominantly in three zones by: elastoplastic deformation in the primary shear zone; friction and extreme elastoplastic deformation in the secondary shear zone between the tool rake face and the chip; and friction at the tool flank face with the newly generated workpiece surface. [P.J. Arrazola et al. / CIRP Annals - Manufacturing Technology 58 (2009), 85]



endoscopic structured-light       

Structured light devices are less mature technologies with accuracy 1 part in 105 but they have potential for achieving higher accuracy than laser line scanners due to the fundamental limits imposed by speckle effects [P.G. Maropoulos, D. Ceglarek / CIRP Annals - Manufacturing Technology 59 (2010), 751]




evlauation consists of the elements descrition, analysis and valuation of processes and results of taken actions




Impact extrusion describes the process of pushing a workpiece trough tool elements to receive a specific component shape



extrusion oil      

Lubricants extended from ordinary extrusion oil to pigmented oil and an emulsion. CVD coatings with TiC + TiN and Me-C:H (DLC) show low friction and attempts to test in industrial production proved promising as regards substituting zinc phosphate layers by applying tool coatings. [N. Bay et al. / CIRP Annals - Manufacturing Technology 59 (2010), 773f]



fiber bundles (with the ability to condut visual signals)  

Image-transmitting fiber bundles are plan in a limited space. Assorted multimode fibers are able to optically transmit images and patterns via the input and output optical system. They are mainly used in medical endoscopy. With the help of improved optics they should be applied for 3D surface measurement technology within the SFB / TR73.



Flange Forming

The formation of a flange on an opening inside a sheet product in a drawing-like operation  [CIRP].



flow curve (rheology)   

flow curves are illustrating the correlation between the degree of deformation and the tension for flexion



flow curve formulation 

The flow curve formualtion is a mathematical descrition of all factors that are influencing the flow curve tensio. Some factors are material influences, temperature and change of shape



FMEA (Failure Mode and Effect Analysis)             

FMEA (Failure Mode and Effect Analysis) is a systematical tool to analysis a system. The focus is set on the identification of possible failures and the failure causes as well as the impact of failures for the system functions




Friction is a force which results from a relative movement of two materials and is always opposed to the movement.



friction shear stress       

friction shear stress describes the friction that is caused by shear stress within a solid. It can be estimated by the coeeficient of friction.



fringe projection (structured-light)         

structured light is the process of projecting a known pattern of pixels (often grids or horizontal bars) on to a scene. The way that these deform when striking surfaces allows vision systems to calculate the depth and surface information of the objects in the scene



functional check of a measuring instrument       

determine wheter a measuring instrument or measuring system meets the requirements



Fuzzy Logic         

Fuzzy logic is a form of many-valued logic that deals with approximate, rather than fixed and exact reasoning. Compared to traditional binary logic variables are not necassary 100% truth or false



Fuzzy Set            

Fuzzy Set describes a bunch of elements with a linked continous membership function that consists of vlaues between 0 and 1.



gaussian distribution     

Form deviation of a machined workpiece is inherent and contributes to measurement uncertainty. Considering the deviation is mainly due to the relative positioning error between the cutting tool and the workpiece, it can be considered as a signal generated by random walks with increments i.e. the relative error motion in each position having Gaussian statistics [C.F. Cheung et al. / CIRP Annals - Manufacturing Technology 63 (2014), 482]



generation of pattern   

Generation of pattern in context with the structurred-light refers to the possibility to project various light patterns (e.g. stripped or sinus pattern) onto a surface. The generated picture can be recorded and used by IT technology.



generator (points)          

set of points that is needed to create a Delauney-triangulation or a Voronoi-diagram



Gradient-index (GRIN) optics    

Optics that do not affect the course of an electromagnetic wave as usual with their ground form but with an internal refractive index profile. They are suitable particularly for low-loss coupling and decoupling optics for glass fibers and fiber bundles




The grain size is the three-dimensional feature, which is scaled down, while the diameter of dislocation loops is the characteristic length. As explained, the Hall–Petch relationship is not valid in copper below a grain size of about 50 nm, as dislocation loops cannot be scaled down to such a grain size. [F. Vollertsen et al. / CIRP Annals - Manufacturing Technology 58 (2009), 567]




see grain




a graph is a network that consists of arcs an vertices



Gray-Code- method      

To clearly evaluate the height information a sequence of different fringes is projected onto the surface (e.g. ‘‘Graycode’’) which makes a reliable correspondence between the projected and detected fringes possible. [A. Weckenmann et al. / CIRP Annals - Manufacturing Technology 58 (2009), 705]




As can be seen, the cutting process is unsuitable for machining of C/C–SiC in this case. The development of new grinding applications in advanced materials should take into consideration unexpected possibilities where grinding can, as shown in this example, be applied in unusual situations. This is a good example on how grinding became a very adequate option due to its specificities related to the material conditions and process geometry. [J.F.G. Oliveira et al. / CIRP Annals - Manufacturing Technology 58 (2009), 668]




see figure




For the histogram, the spread of a feature is divided into classes and shows the frequency of occurrence of each sub-interval graph. The graph gives the possibility to the analyse the distribution of the feature and provides the mean value.




To model structures on a small scale, can be computationally very intensive. The aim is therefore, to smear the material properties to enable that at a higher (less accurate) size scale can be use that represents the material sufficiently accurate.




Hyperelasticity provides a means of modeling the stress-strain behavior of such materials. The behavior of unfilled, vulcanized elastomers often conforms closely to the perelastic ideal. Filled elastomers and biological tissues are also often modeled via the hyperelastic idealization. [, 08.10.2015]



inclination (angle)           

There are two types of rotary tools as shown in Fig. 1. It shows the ordinary well-known self-propelled rotary tool (SPRT). In the SPRT, the tool axis should be inclined at a definite angle b with respect to the workpiece axis so that the tool rotation is derived from the cutting force component in the direction of vt. [A. Hosokawa et al. / CIRP Annals - Manufacturing Technology 59 (2010), 89]




see lubricant indentation




Qualitative or quantitative measurement criterion (parameter, code, code value), which captures the degree to which a defined requirement is fullfilled.



influences on the manufacturing accuracy           

The production accuracy is influenced by six main variables. For example: used material, lubrication, peripherie and human factors




Isotropy is uniformity in all orientations. Precise definitions depend on the subject area. Exceptions, or inequalities, are frequently indicated by the prefix an, hence anisotropy. [, 08.10.2015]



leached roving

The fibers in leached fibre bundels are in a sorted order at the front and end of the light guide. This allows an image transfer without recalculation of the fiber and pixel positions. Image transfer with leached fiber bundles therefore has the potential to produce a lower measurement error as so-called "wound" (unsorted) fiber bundle.



load cycle (damage concept)     

The damage concept describes the relationship between the maximum load and the number of load cycles until the initiation of fatigue cracks for low cycle fatigue [M. Pietrzyk et al. / CIRP Annals - Manufacturing Technology 59 (2010), 321]




As regards sheet metal forming, chlorinated paraffin oils are often used in forming of materials prone to galling such as advanced high strength steels, stainless steel and titanium, as well as in tribologically demanding processes such as punching and ironing, and present a serious environmental concern. Significant research has been expended towards finding alternatives by combining new lubricants with anti-seizure tool materials and coatings [N. Bay et al. / CIRP Annals - Manufacturing Technology 59 (2010), 760]



lubricant indentation     

In studies of plane strip drawing of aluminum provided with artificial lubricant pockets by local indentation with a Vickers pyramid Azushima et al. verified the proposed mechanism by direct observation of the tool/workpiece interface through a transparent die. They showed that lubricant escape from the pockets was influenced by the degree of reduction, drawing speed and lubricant viscosity. [N. Bay et al. / CIRP Annals - Manufacturing Technology 59 (2010), 775]



maturity degree model

Therefore the isoquants can be interpreted as a multidimensional maturity degree model. [G. Schuh et al. / CIRP Annals - Manufacturing Technology 60 (2011), 459] (BILD EINFÜGEN)



maturity level   

The assessment model provides an aggregated evaluation of the process maturity level on different levels of detail (process steps, phases, control loop elements). Additionally, strengths and weaknesses of the process are correlated with different characteristics of the quality control loop. [N.G. Patil et al. / Procedia CIRP 24 ( 2014 ), 88]



maturity level assessment          

maturity level determination to a certain point in time [R. Schmitt et al. / CIRP Annals - Manufacturing Technology 61 (2012), 441]



maturity level validation              

specific actions and methods to ensure the maturity level [R. Schmitt et al. / CIRP Annals - Manufacturing Technology 61 (2012), 441]




particular quantity subject to measurement [Guide to the expression of uncertainty in measurement (2008), 50]




set of operations having the object of determining a value of a quantity [Guide to the expression of uncertainty in measurement (2008), 33]



measurement range     

The laser displacement sensor has a measurement range of 20 mm, which makes it possible to measure surface profiles smaller than its measurement range with linear motion only [S. Nishikawa et al. / Procedia CIRP 24 ( 2014 ), 2]



measurement standard

Often, measuring instruments and systems are adjusted or calibrated using measurement standards and reference materials to eliminate systematic effects; however, the uncertainties associated with these standards and materials must still be taken into account. [Guide to the expression of uncertainty in measurement (2008), 5]



measurement uncertainty          

parameter, associated with the result of a measurement, that characterizes the dispersion of the values that could reasonably be attributed to the measurand [Guide to the expression of uncertainty in measurement (2008), 36]



membership function   

a membership functions gives information about the degree of beloning of a certain elemnt to a set




Manufacturing processes such as hard machining, grinding, electrical discharge machining and surface treatments cause changes to the microstructure and, consequently, to the mechanical properties and quality of the surface. [D. Umbrello, L. Filice / CIRP Annals - Manufacturing Technology 58 (2009), 73]




Defined checkpoints (e.g. in a project) that target dates to evluate on the base of preassigned indicators



monte carlo method     

Monte Carlo methods are a broad class of computational algorithms that rely on repeated random sampling to obtain numerical results.mainly used in three distinct problem classes: optimization, numerical integration, and generation of draws from a probability distribution.



Multi- Sensor Data Fusion           

combination of competitive and complementary sensor data of multiple sensors



observational error        

In general, a measurement has imperfections that give rise to an error in the measurement result. Traditionally, an error is viewed as having two components, namely, a random component and a systematic component. [Guide to the expression of uncertainty in measurement (2008), 5]



observational error / measurement error concerning flatness   

range of signed deviations of measures to a compesating level, that are claculated with the least square method



observational random error       

An uncontrollable, not unidirectional deviation is a random error.



observational systematic error

Systematic error, like random error, cannot be eliminated but it too can often be reduced. If a systematic error arises from a recognized effect of an influence quantity on a measurement result, hereafter termed a systematic effect, the effect can be quantified and, if it is significant in size relative to the required accuracy of the measurement, a correction or correction factor can be applied to compensate for the effect. It is assumed that, after correction, the expectation or expected value of the error arising from a systematic effect is zero. [[Guide to the expression of uncertainty in measurement (2008)]



one factor method         

analytical approach that specifies to change one influencing factor of a system while all other factor are kept constant.



orbital frequency (rotation speed)          

Rotation speed of an object rotating around an axis is the number of turns of the object per time unit, specified as revolutions per minute (rpm) or per second (rps). Rotational speed is equal to the angular velocity ω divided by 2π. [, 08.10.2015]




As a result of the mechanical loadings the material parameters for the modelling are determined as an elastic-orthotropic shell which can be used in the forming simulation for a car body component. [W.-G. Drossel et al. / CIRP Annals - Manufacturing Technology 58 (2009), 281]



passive triangulation     

Photogrammetry is a metrology technique in which the shape, size and position of objects are determined from cross-domain fusion of measurements made on two-mensional images. It can also be classified as a passive triangulation principle, where three- dimensional coordinates of points of interest are calculated via optical triangulation from two or more images taken from different locations. [A. Weckenmann et al. / CIRP Annals - Manufacturing Technology 58 (2009), 709]



PDCA (cycle)     

iterative problem-solving process in four steps: Plan, Do, Check, Act [, 08.10.2015]



phase- shift method      

A solution for approach determines the shape of a partial view by a combination of the phase-shift method for fringe evaluation and a photogrammetric triangulation to calculate the 3D coordinates related to the sensor coordinate system. [A. Weckenmann et al. / CIRP Annals - Manufacturing Technology 58 (2009), 710]




Photogrammetry is a metrology technique in which the shape, size and position of objects are determined from cross-domain fusion of measurements made on two-imensional images. It can also be classified as a passive triangulation principle, where three- dimensional coordinates of points of interest are calculated via optical triangulation from two or more images taken from different locations. [A. Weckenmann et al. / CIRP Annals - Manufacturing Technology 58 (2009), 709]



pin on disc experiment 

Within the investigations the tribological performance of surfaces with geometrically defined microdimples has been evaluated by pin-on-disc experiments on a tribometer. [B. Denkena et al. / CIRP Annals - Manufacturing Technology 59 (2010), 68] (BILD EINFÜGEN CIRPA_799_fig4)



poincaré half space model          

Simulations based on the half space model help to analyse the elastoplastic contact behavior of abrasive surfaces. As the simulation is wokring with the surfaces and not with the volumes as e.g. FEM analysis the calcualation time is significantly shorter. The half space model was validated and calibration by experimetal tests. []




In particular, PCD micro tools are attractive candidates for micromachining silicon materials, and can achieve a high surface integrity in ductile mode machining. [K. Katahira et al. / CIRP Annals - Manufacturing Technology 60 (2011), 591]




The simulation of plasticity takes place by an elastic predictor, all plastic shares are initially "frozen" for the load step. If the yield condition is fulfilled, the stress and deformation can be changed in the plastic corrector.



probing diviation             

radial deviation range of measures to a compensating sphere



process (engineering)   

set of interrelations or actions that are interrelated that transforms input into results



process model 

A proces model illustrates the stages, roles, documents, methods, tooles and activities that are typically used to pass a process




positive trend of a status



quality gate       

Defined checkpoints (e.g. in a project) that target dates to evluate on the base of preassigned indicators. Requirements has to be fullfiled to be able to continue with the project or process



radial return map            

In the predictor-corrector method, the current deformation and stress variables are projected back in the case of a plastic step on an elastic region. This back projection is orthogonal to a defined flow area which encloses the elastic area.



reference degree of deformation           

see degree of deformation



reference model (for processes)             

is an abstract framework or domain-specific ontology consisting of an interlinked set of clearly defined concepts produced by an expert or body of experts in order to encourage clear communication. A reference model can represent the component parts of any consistent idea, from business functions to system components, as long as it represents a complete set.



residual stresses             

The rise of friction coefficient increase the surface residual stresses level in the direction of tensile stress due to the high non-linearly coupled thermal effect (increased surface temperatures, especially at small ploughed depths and mechanical effect (more surface deformations at large ploughed depths). [Y.B. Guo et al. / CIRP Annals - Manufacturing Technology 58 (2009), 83f]




the capability of an optical or other sensor to discern small objects or measurements [, 08.10.2015]



Schmid's law (Schmid factor)     

In the field of crystal plasticity these critical Schmid strains are responsibel for the shearing of metal atoms within the slip system.



sensitivity analysis          

The technique is applied as a method of obtaining sensitivity of information, based on criticality described before. [R. Roy et al. / CIRP Annals - Manufacturing Technology 58 (2009), 172]



sharpness / picture definition   

In the context of structured light projection is the minimum allowed focus defined by the maximum of the evaluable area.



sheet-bulk metal forming           

The process “sheet-bulk metal forming” is investigated to produce functional components with complex geometric features out of a sheet metal by using bulk forming processes like upsetting or extrusion. [M. Merklein & S. Opel / Investigation Of Tailored Blank Production By The Process Class Sheet Bulk Metal Forming (2011)]



Superimposed oscillation            

Introduction of dynamic forces in the main power flow of machine.



surface deformation     

A principal objective of machining is creation of component surfaces with specific attributes that enable functionality of products. From a surface integrity standpoint, deformation levels and microstructure are perhaps the most critical, since these determine mechanical and physical properties. [Y. Guo et al. / CIRP Annals - Manufacturing Technology 60 (2011), 137]



surface pressure             

Two parts with surface contact are suqeezed together what results in surface pressure



tailored blank   

So-called tailored blanks are usually made of different materials or sheet thicknesses. A common way of joining diverse blanks is welding. In most cases the joining has a significant influence on the consecutively forming process due to varying local mechanical properties. [M. Merklein & S. Opel / Investigation Of Tailored Blank Production By The Process Class Sheet Bulk Metal Forming (2011)]


Tailored surfaces             

This paper describes the adaptation of the ring crush test by the terms of sheet-bulk metal forming, in order to qualify Tailored Surfaces and coatings in terms of their influence on the tribological material flow. In addition, innovative processes for the preparation of tailored surfaces and coatings on tool surfaces are explained. By using practical examples and simulation-based studies it is shown how Tailored Surfaces of tools and parts can influence the material flow in sheet-bulk metal forming. []




By analysing the Structure Tensor S of small image regions based on the eigenvector matrix concept, it is possible to determine the local pixel orientation. The tensor defines the orientation of a region, considering the deviation of the grey value course using the fact that the gradients perpendicular to the fibres are higher than in fibre direction. [C. Mersmann / CIRP Annals - Manufacturing Technology 60 (2011), 511]




Topography (surface topography) describes the dimensional shape and onstitution of a mechanical part. It can be meassured by tactil and optical meassurement methods.



Triangulation (chordal graph)     

A triangualtion is a graph whose arcs are combining the set of generator points to triangle-sided figures or in a spatial view they are combined to tetrahedrons.



tribological appearance

Tribological appearances are the characteristical modifications of the contact bodies' surface as well as the formation of wear debris. They depend on the occuring wear mechanisms and on the types of wear.



tribological load               

Quality and type of lubrication which are required to realize tool workpiece separation and friction reduction depend strongly on the tribological loads that appear in a specific process. The tribological load can be mainly characterized by the following parameters: contact normal stresses, surface enlargement, relative velocity between tool and workpiece as well as initial temperature. [N. Bay et al. / CIRP Annals - Manufacturing Technology 59 (2010), 761]



tribological systems       

all technical systems that contain friction and wear processes are called tribological systems. These systems consit of a main body, an antibody, an intermediate and an ambient medium.



true stress         

The rheological tests generate the true stress–true strain curves of the bar material. These curves are then implemented through a rheological law in the FE model of the process in order to provide accurate predictions of the thermal and mechanical parameters in the piercing operation, especially in the material zone where cavities develop.[A. Ghiotti et al. / CIRP Annals - Manufacturing Technology 58 (2009), 256]


true value          

value consistent with the definition of a given particular quantity [Guide to the expression of uncertainty in measurement (2008), 32]



Upsetting / axial forming             

belongs to the main group of forming processes [DIN 8582] Free-form shaping is called axial formning when a workpiece dimension between flat, parallel active surfaces is reduced.[DIN 8583-3]




The assurance that a product, service, or system meets the needs of the customer and other identified stakeholders. It often involves acceptance and suitability with external customers. [IEEE guide--adoption of the Project Management Institute (PMI®) standard (2011), 452]




The evaluation of whether or not a product, service, or system complies with a regulation, requirement, specification, or imposed condition. It is often an internal process. [IEEE guide--adoption of the Project Management Institute (PMI®) standard (2011), 452]



Vertex (graph theory) (node)   

This preprocessing step optimizes the results of the segmentation, during which each vertex of a dataset is classified as plane or notplane. For this classification the normals of neighboring triangles are compared and a vertex is declared as plane, if the variance of the normals lies under a certain threshold. [L. Shaw, A. Weckenmann / CIRP Annals - Manufacturing Technology 60 (2011), 541]




The visualization encompasses all techniques for creating graphics, diagrams and animations for the communication of information. What helps to take actions and make decisions.



Volumetrisch-deviatorischer Split            

For some materials, it is useful to divide the material response in a volume-changing fraction and a volume loyal fraction because they behave different characteristics concerning compression and shear behavior.



von Mises yield criterion (equivalent stress)       

The von Mises yield criterion is used to transfer yield stress of an uniaxial stress state to a multi-axial stress state.



Voronoi diagram             

The Voronoi algorithm utilizes a set of statistically distributed points (seeds) to partition space into region, i.e., Voronoi cells, one per point and hence to approximate a random microstructure. The Voronoi cells are created by considering each point and its nearest neighbours by application of a Delaunay triangulation algorithm. [M. Abouridouane et al. / CIRP Annals - Manufacturing Technology 61 (2012), 73] duality: the voronoi diagram is the dual graph to the delaunay triangulation



Voronoi partition            

see also Voronoi diagram



wall ironing / ironing      

is the reduction in thickness of drawn shell walls by pulling them through tight dies [Machinery’s Handbook 29th Edition].