T V Vorburger,

J Song,

N Petraco

Surface Topography: Metrology and Properties, Год журнала: 2015, Номер 4(1), С. 2 - 35

Опубликована Окт. 6, 2015

The application of surface topography measurement methods to the field of firearm and toolmark analysis is fairly new. The field has been boosted by the development of a number of competing optical methods, which has improved the speed and accuracy of surface topography acquisitions. We describe here some of these measurement methods as well as several analytical methods for assessing similarities and differences among pairs of surfaces. We also provide a few examples of research results to identify cartridge cases originating from the same firearm or tool marks produced by the same tool. Physical standards and issues of traceability are …

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Larisa R G DeSantis

Surface Topography: Metrology and Properties, Год журнала: 2016, Номер 4(2), С. 1 - 12

Опубликована Апрель 1, 2016

Dietary information of fossil mammals can be revealed via the analysis of tooth morphology, tooth wear, tooth geochemistry, and the microscopic wear patterns on tooth surfaces resulting from food processing. Although dental microwear has long been used by anthropologists and paleontologists to clarify diets in a diversity of mammals, until recently these methods focused on the counting of wear features (e.g., pits and scratches) from two-dimensional surfaces (typically via scanning electron microscopes or low-magnification light microscopes). The analysis of dental microwear textures can instead reveal dietary information in a broad range of herbivorous, omnivorous, and carnivorous mammals by characterizing microscopic …

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Abhijeet Gujrati,

Tevis D. B. Jacobs,

Antoine Sanner,

Subarna R. Khanal,

Nicolaie Moldovan,

Hongjun Zeng,

Lars Pastewka

Surface Topography: Metrology and Properties, Год журнала: 2021, Номер 9(1), С. 1 - 1

Опубликована Янв. 1, 2021

The surface topography of diamond coatings strongly affects surface properties such as adhesion, friction, wear, and biocompatibility. However, the understanding of multi-scale topography, and its effect on properties, has been hindered by conventional measurement methods, which capture only a single length scale. Here, four different polycrystalline diamond coatings are characterized using transmission electron microscopy to assess the roughness down to the sub-nanometer scale. Then these measurements are combined, using the power spectral density (PSD), with conventional methods (stylus profilometry and atomic force microscopy) to characterize all scales of topography. The results demonstrate the critical importance of measuring topography across all …

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Ping Lu,

Robert J K Wood

Surface Topography: Metrology and Properties, Год журнала: 2020, Номер 8(4), С. 1 - 1

Опубликована Янв. 1, 2020

Surface textures have been of great interest within the tribology community with nearly 1500 papers published on this topic in the past two decades. With the pursuit of low emissions and environmental sustainability, the application of surface texturing to mechanical systems to lower friction and control wear is attracting increasing attention. There is no doubt that certain textured surfaces can have a beneficial effect on tribological performance but it is widely agreed that the optimization of textures should be carried out based on specific requirements of applications. The purpose of this review article is to summarize the current state of …

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Mark A Purnell,

Laurent P G Darras

Surface Topography: Metrology and Properties, Год журнала: 2015, Номер 4(1), С. 1 - 1

Опубликована Янв. 1, 2015

An understanding of how extinct animals functioned underpins our understanding of past evolutionary events, including adaptive radiations, and the role of functional innovation and adaptation as drivers of both micro- and macroevolution. Yet analysis of function in extinct animals is fraught with difficulty. Hypotheses that interpret molariform teeth in fishes as evidence of durophagous (shell-crushing) diets provide a good example of the particular problems inherent in the methods of functional morphology. This is because the assumed close coupling of form and function upon which the approach is based is weakened by, among other things, behavioural flexibility and the absence of …

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S Lou,

Z Zhu,

W Zeng,

C Majewski,

P J Scott,

X Jiang

Surface Topography: Metrology and Properties, Год журнала: 2021, Номер 9(1), С. 1 - 1

Опубликована Сен. 1, 2021

Surface topography of additively manufactured components often contains 3D features, e.g. particles, open surface pores. X-ray computed topography can capture these features, allowing measurement data to be used for 3D surface texture characterisation. On the basis of the newly developed 3D surface texture parameters, this paper investigates material ratio curves of the surfaces produced by additive manufacturing processes, i.e. selective laser melting and high speed sintering. The material ratio curves of these surfaces vary in their shapes, depending on the specific process and associated process parameters, as well as surface orientations. Re-entrant topography features can result in recess shapes on …

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