AI Article Synopsis
Article Abstract
B-doped diamond has become the ultimate material for applications in the field of microelectromechanical systems (MEMS), which require both highly wear resistant and electrically conductive diamond films and microstructures. Despite the extensive research of the tribological properties of undoped diamond, to date there is very limited knowledge of the wear properties of highly B-doped diamond. Therefore, in this work a comprehensive investigation of the wear behavior of highly B-doped diamond is presented. Reciprocating sliding tests are performed on micro- and nanocrystalline diamond (MCD, NCD) films with varying B-doping levels and thicknesses. We demonstrate a linear dependency of the wear rate of the different diamond films with the B-doping level. Specifically, the wear rate increases by a factor of 3 between NCD films with 0.6 and 2.8 at. % B-doping levels. This increase in the wear rate can be linked to a 50% decrease in both hardness and elastic modulus of the highly B-doped NCD films, as determined by nanoindentation measurements. Moreover, we show that fine-grained diamond films are more prone to wear. Particularly, NCD films with a 3× smaller grain size but similar B-doping levels exhibit a double wear rate, indicating the crucial role of the grain size on the diamond film wear behavior. On the other hand, MCD films are the most wear-resistant films due to their larger grains and lower B-doping levels. We propose a graphical scheme of the wear behavior which involves planarization and mechanochemically driven amorphization of the surface to describe the wear mechanism of B-doped diamond films. Finally, the wear behavior of the nucleation surface of NCD films is investigated for the first time. In particular, the nucleation surface is shown to be susceptible to higher wear compared to the growth surface due to its higher grain boundary line density.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acsami.6b08083 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Effects of computer-generated patterns with different temporal and spatial frequencies on choroidal thickness, retinal dopamine and candidate genes in chickens wearing lenses.
Front Med (Lausanne)
December 2024
Section of Neurobiology of the Eye, Ophthalmic Research Institute, University of Tübingen, Tübingen, Germany.
Purpose: Changes in choroidal thickness (ChT) are proposed to predict myopia development but evidence is mixed. We investigated time courses of choroidal responses, following different types of dynamic artificial stimulation in chicks with and without spectacle lenses, as well as changes in retinal dopamine metabolism and expression of candidate genes.
Methods: Chicks were kept in an arena surrounded by computer monitors presenting dynamic checkerboard fields of small, medium and large size.
Machine learning helps reveal key factors affecting tire wear particulate matter emissions.
Environ Int
December 2024
Tianjin Key Laboratory of Urban Transport Emission Research, College of Environmental Science and Engineering, Nankai University, 1st Floor, Nankai University Press, No.94 weijin Road, Nankai District, Tianjin 300071, China. Electronic address:
Tire wear particles (TWPs) are generated with every rotation of the tire. However, obtaining TWPs under real driving conditions and revealing key factors affecting TWPs are challenging. In this study, we obtained a TWPs dataset by simulating tire wear process under real driving conditions using a tire wear simulator and custom-designed test conditions.
View Article and Find Full Text PDFGraphene Mitigates Nanoscale Tribochemical Wear of Silica Glass in Water.
Small
December 2024
Department of Materials Science and Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India.
Despite the ubiquitous use of glasses, their simultaneous susceptibility toward scratch-induced defects and atmospheric hydration deteriorates their mechanical and chemical durability. Here, it is demonstrated that the deposition of a few-layer graphene provides unprecedented wear resistance to silica glass in aqueous conditions. To this extent, nanoscale scratch tests are carried out on graphene-glass surfaces via contact-mode atomic force microscopy with chemically inert and reactive tips.
View Article and Find Full Text PDFCurrent Knowledge on Craniodental Anatomy and Dental Pathology in Golden Snub-Nosed Monkeys (Rhinopithecus roxellana): A Comparative Review.
Zoo Biol
December 2024
Department of Stomatology, Tongji Medical College, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China.
The Sichuan golden snub-nosed monkey (Rhinopithecus roxellana) is a rare and endangered species endemic to China that occupies a particularly important position in the evolutionary history of Rhinopithecus species. Oral health is a crucial aspect of overall well-being in both humans and nonhuman primates. We review the current limited literature on the dental characteristics and dental pathologies related to the golden snub-nosed monkey, based on skeleton data and morphological evidence.
View Article and Find Full Text PDFExperimental and computational evaluation of knee implant wear and creep under in vivo and ISO boundary conditions.
Biomed Eng Online
December 2024
Laboratory for Mechanical Systems Engineering, Empa, Dübendorf, Switzerland.
Background: Experimental knee implant wear testing according to ISO 14243 is a standard procedure, but it inherently possesses limitations for preclinical evaluations due to extended testing periods and costly infrastructure. In an effort to overcome these limitations, we hereby develop and experimentally validate a finite-element (FE)-based algorithm, including a novel cross-shear and contact pressure dependent wear and creep model, and apply it towards understanding the sensitivity of wear outcomes to the applied boundary conditions.
Methods: Specifically, we investigated the application of in vivo data for level walking from the publicly available "Stan" data set, which contains single representative tibiofemoral loads and kinematics derived from in vivo measurements of six subjects, and compared wear outcomes against those obtained using the ISO standard boundary conditions.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!