MICROSTRUCTURE EVOLUTION OF GOLD ATOMIC AGGREGATES FABRICATED ON SILICONE OIL SURFACE

Gold atomic aggregates are fabricated by vapor-depositing Au atoms onto a silicone oil surface and the microstructure evolution is investigated by atomic force microscopy (AFM) observation. It is found that the Au aggregates are composed of Au circular nanoparticles with diameter around 45 nm, which is independent with the nominal film thickness d. As d increases from 1 nm to 15 nm, the height of the nanoparticles increases from 15 nm to 25 nm, indicating the geometric shape of the Au nanoparticles evolves from plateau to spherical. Furthermore, the roughness analysis shows that the mean surface roughness increases linearly with d in the range of 1 nm–15 nm, which is quite different from the findings in Ag system. The anomalous microstructure evolution of Au aggregates suggests that the growth of Au aggregates may be dominated by the shadowing effect.

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Assessing the Functional Properties of TiZr Nanotubular Structures for Biomedical Applications, through Nano-Scratch Tests and Adhesion Force Maps

Molecules ◽

10.3390/molecules26040900 ◽

2021 ◽

Vol 26 (4) ◽

pp. 900

Author(s):

Maria Vardaki ◽

Aida Pantazi ◽

Ioana Demetrescu ◽

Marius Enachescu

Keyword(s):

Surface Roughness ◽

Functional Properties ◽

Bacterial Adhesion ◽

Biomedical Applications ◽

Adhesion Force ◽

Roughness Parameters ◽

Force Microscopy ◽

Atomic Force ◽

The Mean ◽

Scratch Tests

In this work we present the results of a functional properties assessment via Atomic Force Microscopy (AFM)-based surface morphology, surface roughness, nano-scratch tests and adhesion force maps of TiZr-based nanotubular structures. The nanostructures have been electrochemically prepared in a glycerin + 15 vol.% H2O + 0.2 M NH4F electrolyte. The AFM topography images confirmed the successful preparation of the nanotubular coatings. The Root Mean Square (RMS) and average (Ra) roughness parameters increased after anodizing, while the mean adhesion force value decreased. The prepared nanocoatings exhibited a smaller mean scratch hardness value compared to the un-coated TiZr. However, the mean hardness (H) values of the coatings highlight their potential in having reliable mechanical resistances, which along with the significant increase of the surface roughness parameters, which could help in improving the osseointegration, and also with the important decrease of the mean adhesion force, which could lead to a reduction in bacterial adhesion, are providing the nanostructures with a great potential to be used as a better alternative for Ti implants in dentistry.

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TEMPERATURE EFFECT ON MICROSTRUCTURE AND AGGREGATION BEHAVIOR OF GOLD ATOMIC AGGREGATES ON SILICONE OIL SURFACE

Surface Review and Letters ◽

10.1142/s0218625x16500530 ◽

2016 ◽

Vol 23 (06) ◽

pp. 1650053

Author(s):

YUANXIN FENG ◽

CHUHANG ZHANG

Keyword(s):

Au Nanoparticles ◽

Silicone Oil ◽

Three Dimensional ◽

Average Height ◽

Average Width ◽

Thermal Evaporation Method ◽

Aggregation Mechanism ◽

Force Microscopy ◽

Atomic Force ◽

Atomic Force Microscopy Observation

By thermal evaporation method, gold (Au) atomic aggregates were fabricated on a silicone oil surface and the aggregation mechanism was investigated. It is found that the apparent surface coverage ([Formula: see text]) of the Au aggregates dropped obviously, from 15% to 12% as the oil temperature (T) increased from 285[Formula: see text]K to 353[Formula: see text]K. Meanwhile, the average width of the aggregates gradually increased from 0.36[Formula: see text][Formula: see text]m to 0.50[Formula: see text][Formula: see text]m, indicating the aggregates combine with each other as T increased. By the atomic force microscopy observation, Au nanoparticles with diameter around 45.0 nm were observed in the aggregates, which were independent with T. Similarly, the average height of the aggregates found remain unchanged at around 10.0[Formula: see text]nm as T increased. The anomalous aggregation mechanism of Au aggregates suggests that a compact microstructure for Au aggregates is preferred at high T rather than three-dimensional (3D) growth, which is quite different from that of Ag aggregates.

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Surface Roughness

Tribology on the Small Scale ◽

10.1093/oso/9780199609802.003.0002 ◽

2019 ◽

pp. 28-53

Author(s):

C. Mathew Mate ◽

Robert W. Carpick

Keyword(s):

Surface Roughness ◽

Atomic Force Microscopy ◽

Contact Friction ◽

Radius Of Curvature ◽

Roughness Parameters ◽

Force Microscopy ◽

Fractal Surfaces ◽

Atomic Force ◽

The Mean ◽

Physical Phenomena

When two surfaces are brought into contact, they first touch where the summits of the surface asperities make contact. Consequently, surface roughness or topography strongly influences those physical phenomena associated with contact: friction, adhesion, and wear. This chapter discusses techniques for measuring the roughness of surfaces and the parameters frequently used to characterize this roughness. As atomic force microscopy (AFM) and optical interferometry are currently the predominant tools for characterizing roughness, these techniques are discussed at some length. Examples are given for determining not only the standard roughness parameters (the standard deviation of surface heights, the mean radius of curvature of asperity summits, waviness, and the average and rms of surface heights), but also for determining the surface roughness power spectrum, which has gained importance in recent tribology theories. The topography of self-affine fractal surfaces is also discussed along with the tribological importance of these surfaces.

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Comparative effect of three polishing systems on porcelain surface roughness after orthodontic bracket debonding and composite resin removal: An atomic force microscopy

APOS Trends in Orthodontics ◽

10.25259/apos_7_2019 ◽

2019 ◽

Vol 9 ◽

pp. 223-229

Author(s):

Faeze Qabel ◽

Riehane Talaei ◽

Saeedeh Saeedi ◽

Raheb Ghorbani ◽

Nazila Ameli

Keyword(s):

Surface Roughness ◽

Atomic Force Microscopy ◽

Composite Resin ◽

Cost Effective ◽

Orthodontic Bracket ◽

Force Microscopy ◽

Atomic Force ◽

The Mean ◽

Level Of Significance ◽

One Way Anova

Purpose: Porcelain polishing after orthodontic bracket debonding and resin removal is imperative to eliminate surface roughness and minimize the risk of plaque accumulation, periodontal disease, and porcelain discoloration. This study aimed to assess the effect of three polishing systems on porcelain surface roughness after orthodontic bracket debonding. Materials and Methods: Thirty porcelain blocks were divided into three groups. Surface roughness of the samples was first measured using atomic force microscopy (AFM) and recorded as baseline. Orthodontic brackets were bonded to blocks by composite resin. After bracket debonding, resin remnants were removed by tungsten carbide bur. The blocks were then polished with Sof-Lex discs, Meisinger, and Jota porcelain polishing kit. Surface roughness was measured again using AFM. The Shapiro–Wilk test, one-way ANOVA, and Tukey’s post hoc test were used for data analysis through SPSS version 18.0. Level of significance was set at 5%. Results: The mean change in surface roughness after polishing with Jota kit (56.6 nm) was significantly greater than that compared to Sof-Lex discs (10.7 nm) (P = 0.003) and Meisinger kit (26.6 nm) (P = 0.024). The mean change in surface roughness was not significantly different between Sof-Lex and Meisinger groups. Surface roughness significantly increased in all three groups (P < 0.05). Conclusion: Meisinger polishing kit and Sof-Lex discs were not significantly different in terms of the resultant surface roughness. Thus, the conventional use of Sof-Lex discs seems to be more cost-effective due to their lower cost.

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Characterization of Healthy and Fluorotic Enamel by Atomic Force Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927610093748 ◽

2010 ◽

Vol 16 (5) ◽

pp. 531-536 ◽

Cited By ~ 4

Author(s):

Verónica Zavala-Alonso ◽

Gabriel A. Martínez-Castanon ◽

Nuria Patiño-Marín ◽

Humberto Terrones ◽

Kenneth Anusavice ◽

...

Keyword(s):

Surface Roughness ◽

Atomic Force Microscopy ◽

Depth Profile ◽

Positive Association ◽

Clinical Findings ◽

Mean Values ◽

Force Microscopy ◽

Atomic Force ◽

The Mean

AbstractThe aim was to characterize the external structure, roughness, and absolute depth profile (ADP) of fluorotic enamel compared with healthy enamel. Eighty extracted human molars were classified into four groups [TFI: 0, control (C); 1–3, mild (MI); 4–5, moderate (MO); 6–9, severe fluorosis (S)] according to the Thylstrup-Fejerskov Index (TFI). All samples were analyzed by atomic force microscopy.The mean values of enamel surface roughness (ESR) in nm were: Group C, 92.6; Group MI, 188.8; Group MO, 246.9; and Group S, 532.2. The mean values of absolute depth profile in nm were: C, 1,065.7; MI, 2,360.7; MO, 2,536.7; and S, 6,146.2. The differences between mean ESR and mean ADP among groups were statistically significant (p < 0.05). This structural study confirms at the nanometer level that there is a positive association between fluorosis severity, ESR, and ADP, and there is an association with the clinical findings of fluorosis measured by TFI as well.

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Investigating the Effect of Process Parameters in Incremental Sheet Forming Process

Advances in Civil and Industrial Engineering - Data-Driven Optimization of Manufacturing Processes ◽

10.4018/978-1-7998-7206-1.ch003 ◽

2021 ◽

pp. 24-36

Author(s):

Manish Oraon ◽

Manish Kumar Roy ◽

Vinay Sharma

Keyword(s):

Surface Roughness ◽

Process Parameters ◽

Sheet Forming ◽

Incremental Sheet Forming ◽

Forming Process ◽

Batch Production ◽

Force Microscopy ◽

Atomic Force ◽

Roughness Analysis ◽

Step Down

Incremental sheet forming (ISF) is an emerging technique of sheet metal working that comes into the picture in the last two decades. The ISF involved the forming of shapes without using the dedicated dies. ISF is suitable for customized products, rapid prototyping, and low batch production. The study aims to investigate the effect of process parameters on the surface roughness. The experiments are conducted on aluminum AA3003-O grade with six parameters, and the trials are performed according to the design of experiment (DOE). The atomic force microscopy (AFM) technique is used for measuring the surface roughness. Analysis of variance (ANOVA) is used for analyzing the effect of process parameters in ISF. The result shows that the step-down size, feed rate of the tool, and wall angle are significant process parameter and their contributions for ISF are 85.86%, 1.12%, and 12.29%, respectively.

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Anisotropy of Surface Roughness on Aluminium Sheet Studied by Atomic Force Microscopy

Microscopy and Microanalysis ◽

10.1007/s100059910013 ◽

2000 ◽

Vol 6 (2) ◽

pp. 137-144 ◽

Cited By ~ 2

Author(s):

George W. Ryan

Keyword(s):

Surface Roughness ◽

Rolling Direction ◽

Rolling Process ◽

Root Mean Square Roughness ◽

Force Microscopy ◽

Aluminium Sheet ◽

Atomic Force ◽

Lubrication Performance ◽

Microscope Images ◽

The Mean

Atomic force microscope images of aluminium sheet are used to calculate the mean roughness Ra and the root mean square roughness Rq for different directions ([theta]) across the samples. The angle determined values of Ra([theta] and Rq([theta]) are significantly lower in the rolling direction than in any other direction. The results provide a clear demonstration of the vector nature of surface roughness. Local features in an angle determined Rq([theta]) profile are also compared with the positions of peaks and valleys in the matching topographical crosssection of the surface running at right angles to [theta]. It is further found that the distribution of z heights for an imaged sample is usually not Gaussian in shape unless the z heights are measured about mean lines constructed across the surface parallel with the rolling direction. The results are relevant for controlling lubrication performance in the aluminium rolling process.

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Effect of Dental Finishing Instruments on the Surface Roughness of Composite Resins as Elucidated by Atomic Force Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927608080768 ◽

2008 ◽

Vol 14 (5) ◽

pp. 380-386 ◽

Cited By ~ 18

Author(s):

Ana Carolina Botta ◽

Sillas Duarte ◽

Pedro Iris Paulin Filho ◽

Simoni Maria Gheno

Keyword(s):

Surface Roughness ◽

Composite Resin ◽

Composite Resins ◽

Contact Mode ◽

Force Microscopy ◽

Diamond Bur ◽

Atomic Force ◽

The Mean ◽

Student’S T ◽

Student’S T Test

AbstractRoughness increases significantly after finishing procedures. The aim of this study was to assess by the atomic force microscope (AFM) the effect of finishing instruments on the surface roughness of composite resins. A nanofiller composite resin (Filtek Supreme, 3M–F) and a microhybrid composite resin (Point 4, Kerr–P) were selected. The finishing procedures were done with a 30-blade carbide bur (C) and a 30-μm finishing diamond bur (D). Standardized specimens were produced and divided into six experimental groups (n= 4) according to (1) composite resin, (2) absence of finishing (Mylar matrix–M), and (3) finishing instrument (FM, PM, FC, FD, PC, PD). The mean surface roughness was evaluated by AFM in the contact mode. FM and PM groups were assessed statistically by the Student's T test, and FC, FD, PC, PD groups were submitted to variance analysis (ANOVA), both at 5% significance. The mean surface roughness values, in nanometers, were FM, 23.63 (b); FC, 283.88 (c); FD, 510.55 (d); PM, 12.52 (a); PC, 343.98 (c); PD, 531.64 (d). Microhybrid composite displayed less roughness than nanofiller composite in the absence of finishing procedures. The 30-blade carbide bur produced less roughness compared to the extra fine diamond bur.

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Pt Hillock Formation and Decay

MRS Proceedings ◽

10.1557/proc-361-257 ◽

1994 ◽

Vol 361 ◽

Cited By ~ 25

Author(s):

Scott R. Summerfelt ◽

Dave Kotecki ◽

Angus Kingon ◽

H.N. Al-Shareef

Keyword(s):

Surface Roughness ◽

Electron Beam Evaporation ◽

Dielectric Thickness ◽

Force Microscopy ◽

Si Substrates ◽

Atomic Force ◽

Hillock Formation ◽

Roughness Analysis ◽

High Dielectric

ABSTRACTThe formation of Pt hillocks during high temperature processing is a problem when using Pt as a bottom electrode for high dielectric constant materials. The hillock height is frequently larger than the dielectric thickness, degrading the leakage current of the device. In this work, Pt was deposited by electron beam evaporation on in-situ formed 40 nm ZrO2 coated SiO2 / Si substrates. The samples were then annealed at temperatures between 400°C and 700°C for times ranging from 2 min to 40 min. The surface roughness was measured by atomic force microscopy (AFM). The surface was characterized using Ra, RMS and Zmax over 5 μm × 5μm regions. Zmax is sensitive to hillock formation and Ra is sensitive to changes in general surface roughness. Analysis of Zmax indicates that 100 nm Pt / ZrO2 deposited at 315°C forms hillocks above 450°C during initial heatup. Subsequently, the hillocks decay for temperatures of 600°C and above such that they are almost gone after a 30 min air anneal. In-situ wafer stress measurements of Pt / ZrO2 were performed in O2 at temperatures up to 650°C. The Pt relaxes above 500°C in O2.

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