The interaction of cells and bacteria with surfaces structured at the nanometre scale.

https://www.kubiak.co.uk/publication/Kubiak2011.pdf

Wettability versus roughness of engineering surfaces

The paper reviews published data which address the effect of machining (conventional and non-conventional processes) and the resulting workpiece surface topography/integrity on fatigue performance, for a variety of workpiece materials. The effect of post-machining surface treatments, such as shot peening, are also detailed. The influence of amplitude height parameters (Ra, Rt), amplitude distribution (Rsk) and shape (Rku) parameters, as well as spatial (Std, Sal) and hybrid (Ssc) measures, are considered.

There is some disagreement in the literature about the correlation between workpiece surface roughness and fatigue life. In most cases, it has been reported that lower roughness results in longer fatigue life, but that for roughness values in the range 2.5–5 μm Ra it is primarily dependent on workpiece residual stress and surface microstructure, rather than roughness. In the absence of residual stress, machined surface roughness in excess of 0.1 μm Ra has a strong influence on fatigue life. Temperatures above 400 °C reduce the effects of both residual stress and surface roughness on fatigue, due to stress relieving and the change in crack initiation from the surfaces to internal sites. The presence of inclusions an order of magnitude larger than the machined surface roughness generally overrides the effect of surface topography.

The effect of machined topography and integrity on fatigue life

This book draws upon the science of tribology to understand, predict and improve abrasive machining processes. Pulling together information on how abrasives work, the authors, who are renowned experts in abrasive technology, demonstrate how tribology can be applied as a tool to improve abrasive machining processes. Each of the main elements of the abrasive machining system are looked at, and the tribological factors that control the efficiency and quality of the processes are described. Since grinding is by far the most commonly employed abrasive machining process, it is dealt with in particular detail. Solutions are posed to many of the most commonly experienced industrial problems, such as poor accuracy, poor surface quality, rapid wheel wear, vibrations, work-piece burn and high process costs. This practical approach makes this book an essential tool for practicing engineers. Uses the science of tribology to improve understanding and of abrasive machining processes in order to increase performance, productivity and surface quality of final products. A comprehensive reference on how abrasives work, covering kinematics, heat transfer, thermal stresses, molecular dynamics, fluids and the tribology of lubricants. Authoritative and ground-breaking in its first edition, the 2nd edition includes 30 per cent new and updated material, including new topics such as CMP (Chemical Mechanical Polishing) and precision machining for micro-and nano-scale applications.

Tribology of Abrasive Machining Processes

Modern landscape ecology is based on the patch mosaic paradigm, in which landscapes are conceptualized and analyzed as mosaics of discrete patches. While this model has been widely success- ful, there are many situations where it is more meaningful to model landscape structure based on continuous rather than discrete spatial heterogeneity. The growing field of surface metrology offers a variety of surface metrics for quantifying landscape gradients, yet these metrics are largely unknown and/ or unused by landscape ecologists. In this paper, we describe a suite of surface metrics with potential for landscape ecological application. We assessed the redundancy among metrics and sought to find groups of similarly behaved metrics by examining metric performance across 264 sample landscapes in western Turkey. For comparative purposes and to evaluate the robustness of the observed patterns, we examined 16 different patch mosaic models and 18 different landscape gradient models of landscape structure. Surface metrics were highly redundant, but less so than patch metrics, and consistently aggregated into four cohesive clusters of similarly behaved metrics representing surface roughness, shape of the surface height distribution, and angular and radial surface texture. While the surface roughness metrics have strong analogs among the patch metrics, the other surface components are largely unique to landscape gradients. We contend that the surface properties we identified are nearly universal and have potential to offer new insights into landscape pattern-process relationships.

https://www.fs.fed.us/rm/pubs_other/rmrs_2009_mcgarigal_k001.pdf

Surface metrics: an alternative to patch metrics for the quantification of landscape structure

1. Updating introduction to this revised reprint 2. An integrated approach to the assessment of 3-D micro-topography 3. Techniques and fidelity of data collection 4. Measurement strategy of the stylus instrument 5. Effects of stylus geometry and loading 6. Fidelity of the measurement datum 7. The selection of sampling conditions 8. Specification for a unified data file format 9. Reference for 3-D topography characterisation 10. Digital filtering of 3-D surface topography 11. Characterisation techniques 12. Parameters for characterising 3-D surfaces 13. The effects of quantisation on 3-D topography characterisation 14. Functional characterisation of engineering surfaces 15. Calibration of surface topography instruments.

K J Stout

Papers

Development of methods for the characterisation of roughness in three dimensions