Evaluation of the surface topography after precision machining
Wojciech Kacalak
Robert Tomkowski
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Abstract
Analysis of the geometric features and determination of the condition of the surfaces machined during an abrasive process is of crucial importance for evaluation of their wear properties. Numerous parameters can be used for assessing topography of technical surfaces. Many of them contain information that is general or poorly correlated with the wear features. The group of parameters used for such purpose should include those that do not cause information redundancy and provide distinct information. Evaluation of the surface geometric structure after precision machining is a difficult process due to the limited scope of unevenness heights that fit within the range of a few micrometers to a few nanometers. In this paper the synthetic indexes of the evaluation of extra smooth surfaces were created, taking into consideration numerous elementary parameters. The value of the synthetic index was determined as the geometric average of the partial indexes which, when compared to the arithmet...
Key takeaways
- • In the first step the surface parameters must be determined, e.g. amplitude parameters, i.e.
- The last partial coefficient that refers to the summit dispersal on the surface is the ratio of the average distance between the summits and the maximal distance (8).
- This results from the fact that the standard parameters (authors mean the normalized parameters) often do not reflect the character of the surface.
- The next step was analyzing the surface topography using the evaluation coefficients developed by the authors.
- Parameter Sz indirectly informs about the unevenness height and it is not sensitive to the influence of single random summits and pits.
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