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Abstract

This paper presents application of optical microscope for evaluation of microtexture changes of coarse aggregate during simulated polishing in laboratory. Observations of the apparent changes on surfaces of seven different aggregates are presented. Simulation polishing of aggregate was performed in accordance with PN-EN 1097-8:2009. lmages of the aggregate surface were taken with the optical microscope in the reflection mode in particular stages of polishing. Digital images were analyzed. Standard deviation was determined on the basis of the histogram of intensities from digital images of the surfaces of aggregate grains which was assurned as the measure of changes in microtexture during simulated polishing (namely the σh parameter). Statistical analysis has shown that the changes of the σh parameter between the particular stages of polishing confirm certain trends related to the petrographic characteristic of the rocks. Aggregates which included minerals of similar hardness (granodiorite, dolomile, basalt) were more prone to polishing than gabbro and postglacial. Regeneration of the microtexture, the recovery to its original asperity, occurred in the case of quartz sandstone and steelmaking slag.

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Authors and Affiliations

W. Gardziejczyk
M. Wasilewska
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Abstract

WC-8Co cemented carbide was prepared by a high-temperature liquid phase sintering in argon at 5-200 Pa. Three microtextured grooves with a spacing of 500, 750, and 1000 μm were prepared on the surface of WC-8Co cemented carbide. TiAlCrSiN multi-element hard coating was deposited on the WC-8Co cemented carbide microtextured surface with multi-arc ion plating technology. The Vickers hardness and fracture toughness of coated and uncoated WC-8Co cemented carbide with or without a microtextured surface were investigated. The effect of different microtextured spacing on the interface bonding strength of the TiAlCrSiN coating was analyzed. The results show that with the reduction of the microtextured spacing, the Vickers hardness of the cemented carbide slightly decreases, and the fracture toughness slightly increases. The microtextured surface can improve the interface bonding strength between the coating and the substrate. The smaller the microtextured spacing, the larger the specific surface area and the higher the surface energy, so the interface bonding strength between the coating and the substrate increases.
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Authors and Affiliations

ManFeng Gong
1 2
GuangFa Liu
1 2
Meng Li
1 3
XiaoQun Xia
1
Lei Wang
1
ORCID: ORCID
JianFeng Wu
1 2
ShanHua Zhang
1 2
Fang Mei
1

  1. Lingnan Normal University, School of Mechatronics Engineering, Zhanjiang 524048, China
  2. Guangdong Ocean University, School of Mechanical Engineering, Zhanjiang 524088, China
  3. Northwestern Polytechnical University, School of Materials Science and Engineering, Xian 710072, China
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Abstract

Eighteen sediment samples from a 36 cm long sediment core retrieved from a proglacial lake (namely P 11) situated in the Schirmacher Oasis, East Antarctica, were analysed for the study of quartz grain morphology and microtexture, along with sand percentage, to reconstruct the paleoenvironmental changes in the lake during the Holocene. The age of the core ranges from 3.3 ka BP to 13.9 ka BP. The quartz grain morphology and microtexture reveal significant evidences of glacial transport along with some eolian and aqueous activities. On the basis of predominance of these signatures and the zonation from CONISS Cluster Analysis on the percentages of characteristic grain morphology and microtextures, the entire core has been subdivided into three major zones. From the paleoenvironmental perspective, it can be concluded that there is an onset of interglacial period at the advent of Holocene (12.3 ka BP), which reigned until 5.3 ka BP and thereafter, again a glacial environment prevailed until 3.3 ka BP with some variations in-between. The results indicate probable alternative colder and less colder phases in the study area, which are also well supported by the respective sand percentages in the sediments. © 2017 Polish Academy of Sciences 2017.
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Authors and Affiliations

Abhijit Mazumder
Pawan GOVIL
Ratan Kar
Narath Meethal Gayathri
RAGHURAM
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Abstract

The present research work involves the study of the 3-D surface microtexture of sputtered indium tin oxide (ITO) prepared on glass substrates by DC magnetron at room temperature. The samples were annealed at 450°C in air and were distributed into five groups, dependent on ambient combinations applied, as follows: I group, using argon (Ar); II group, using argon with oxygen (Ar+O2); III group, using argon with oxygen and nitrogen (Ar+O2+N2); IV group, using argon with oxygen and hydrogen (Ar+O2+H2); and V group, using argon with oxygen, nitrogen, and hydrogen (Ar+O2+N2+H2). The characterization of the ITO thin film surface microtexture was carried out by atomic force microscopy (AFM). The AFM images were stereometrically quantitatively analyzed to obtain statistical parameters, by ISO 25178-2: 2012 and ASME B46.1-2009. The results have shown that the 3-D surface microtexture parameters change in accordance with different fabrication ambient combinations.
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Authors and Affiliations

Ş. Ţălu
1
ORCID: ORCID
S. Kulesza
2
ORCID: ORCID
M. Bramowicz
2
ORCID: ORCID
K. Stępień
3
ORCID: ORCID
D. Dastan
4

  1. Technical University of Cluj-Napoca, The Directorate of Research, Development and Innovation Management (DMCDI), Cluj-Napoca, 400020, Romania
  2. University of Warmia and Mazury in Olsztyn, Faculty of Technical Sciences, 11 Oczapowskiego Str., 10-719 Olsztyn, Poland
  3. Kielce University of Technology, Faculty of Mechatronics and Mechanical Engineering, Aleja 1000-lecia Państwa Polskiego 7, 25-314 Kielce, Poland
  4. Georgia Institute of Technology, School of Materials Science and Engineering, Atlanta, Georgia 30332, USA

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