Frequency Analysis And Filtering Of Surface Profile Data

1987 ◽  
Author(s):  
Scott L. DeVore
Keyword(s):  
Frequency Analysis ◽  
Surface Profile ◽  
Profile Data

RkRk material measure

2019 ◽  
Vol 86 (9) ◽  
pp. 478-486 ◽  
Author(s):  
Jörg Seewig ◽  
Matthias Eifler ◽  
Dorothee Hüser ◽  
Rudolf Meeß
Keyword(s):  
Surface Profile ◽  
Profile Data ◽  
Measuring Process ◽  
Suitable Material ◽  
Precision Turning ◽  
Functional Characterisation ◽  
Ultra Precision ◽  
Measured Profile ◽  
Material Measure ◽  
Comparison Measurements

AbstractThe standard ISO 13565-2 defines the Rk parameters for the functional characterisation of technical surfaces. So far, no particular material measures for the calibration of these parameters have been defined in the international standardization. For the application and the functional behaviour of technical surfaces the Rk parameters however have a critical significance, so there is a demand by the industry to calibrate these parameters as they are increasingly applied for the quality assessment of workpieces. In the present paper, a proposal for suitable material measures is presented. An algorithm is described, which transforms the data of a real measured profile in a way that the exact defined parameters of Rk, Rpk and Rvk are equated. The material measures geometry corresponds to its later application and the target parameters are almost freely selectable. The approach for transforming surface profile data with the aid of the Abbott curve is introduced generically, solves an inverse problem and considers the influences from the manufacturing and measuring process. The designed material measure is manufactured with the aid of ultra-precision turning. In matters of the aspired industrial application, comparison measurements are carried out in order to examine the practical abilities of the material measure and the repeatability of the approach is proven.

Modeling of Contact Area, Contact Force, and Contact Stiffness of Mechanical Systems With Friction

Tribology ◽  
2005 ◽  
Author(s):  
Jamil Abdo ◽  
Elhanafi Shamseldin
Keyword(s):  
Contact Force ◽  
Contact Area ◽  
Contact Stiffness ◽  
Surface Profile ◽  
Test Area ◽  
Contact Forces ◽  
Profile Data ◽  
Contact Parameter ◽  
Parameter Values ◽  
True Contact Area

It is well recognized that the contact stiffness, true contact area, and the contact force are among the key features in the study of friction system behavior. This paper presents the development of formulae for the mechanical component of dry-friction at the interface of two microscopic rough surfaces. Elastic deformation under the influence of the contact forces is considered. The elastic contact model formulation between interacting asperities is not assumed to occur only at asperity peaks, thus allowing the possibility of oblique contacts wherein the local contact surfaces are no longer parallel to the mean planes of the mating surfaces. It is shown that the approach enables the separation of the contact area into its normal and tangential projections and the contact force into its normal and tangential components. The mathematical model of contact is utilized to develop formulae for normal and tangential contact stiffness. The analytical method is used to estimate contact stiffness components. Contact parameter values for the sample are derived from the surface profile data taken from a 1.0-mm by 10-mm test area. The profile is measured using a Mahr profilometer. A computer program is written and used to analyze the profile data. The analysis yields the asperity density, average asperity radius, and the standard deviation for each test area.

Identification of Plastic Properties From Conical Indentation Using a Bayesian-Type Statistical Approach

2018 ◽  
Vol 86 (1) ◽  
Author(s):  
Yupeng Zhang ◽  
Jeffrey D. Hart ◽  
Alan Needleman
Keyword(s):  
Indentation Depth ◽  
Statistical Approach ◽  
Surface Profile ◽  
Uniaxial Stress ◽  
Strain Response ◽  
Profile Data ◽  
Stress Strain ◽  
Plastic Properties ◽  
Indentation Force ◽  
Depth Response

The plastic properties that characterize the uniaxial stress–strain response of a plastically isotropic material are not uniquely related to the indentation force versus indentation depth response. We consider results for three sets of plastic material properties that give rise to essentially identical curves of indentation force versus indentation depth in conical indentation. The corresponding surface profiles after unloading are also calculated. These computed results are regarded as the “experimental” data. A simplified Bayesian-type statistical approach is used to identify the values of flow strength and strain hardening exponent for each of the three sets of material parameters. The effect of fluctuations (“noise”) superposed on the “experimental” data is also considered. We build the database for the Bayesian-type analysis using finite element calculations for a relatively coarse set of parameter values and use interpolation to refine the database. A good estimate of the uniaxial stress–strain response is obtained for each material both in the absence of fluctuations and in the presence of sufficiently small fluctuations. Since the indentation force versus indentation depth response for the three materials is nearly identical, the predicted uniaxial stress–strain response obtained using only surface profile data differs little from what is obtained using both indentation force versus indentation depth and surface profile data. The sensitivity of the representation of the predicted uniaxial stress–strain response to fluctuations increases with increasing strain hardening. We also explore the sensitivity of the predictions to the degree of database refinement.

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