Effect of Film Thickness on the Rheological Properties of Asphalts in Contact with Aggregate Surface

1998 ◽  
Vol 1638 (1) ◽  
pp. 31-39 ◽  
Author(s):  
Shin-Che Huang ◽  
Jan F. Branthaver ◽  
Raymond E. Robertson ◽  
Sang-Soo Kim
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Rheological Properties ◽  
Thickness Effect ◽  
Asphalt Binders ◽  
Shear Rates ◽  
Service Environment ◽  
Asphalt Mix ◽  
Plate Geometry ◽  
Low Shear

The effect of the interaction between aggregate and asphalt on asphalt mix properties has been a subject of many studies. However, studies using compacted mixtures cannot isolate the pure effects of the asphalt-aggregate interactions, while studies using mixtures of asphalt and fines cannot determine the asphalt rheology at the interface. In this study, direct measurement of asphalt rheology at the interface is investigated using the sliding plate geometry with machined aggregate plates. Significant differences in the behavior of asphalts in contact with aggregate plates have been observed, especially at low shear rates. One asphalt shows substantial aggregate surface-induced structuring, while another asphalt shows essentially none. In addition, the film thickness effect on the rheological properties of asphalt binders and asphalt aggregate mixtures was investigated. The results strongly show that thin films of asphalt on an aggregate surface have substantially changed rheological properties that are asphalt composition–dependent, and that asphalts that are graded alike as bulk materials do not have the same rheological properties as thin films, in this service environment.

Dependence of Film Thickness on Properties of Al Doped ZnO Thin Films

2011 ◽  
Vol 194-196 ◽  
pp. 2305-2311
Author(s):  
Ying Ge Yang ◽  
Dong Mei Zeng ◽  
Hai Zhou ◽  
Wen Ran Feng ◽  
Shan Lu ◽  
...  
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Electrical Parameter ◽  
Substrate Surface ◽  
Rf Magnetron Sputtering ◽  
Thickness Effect ◽  
Visible Range ◽  
Glass Substrates ◽  
Doped Zno

In this study high quality of Al doped ZnO (ZAO) thin films were prepared by RF magnetron sputtering on glass substrates at room temperature in order to study the thickness effect upon their structure, electrical and optical properties. XRD results show that the films are polycrystalline and with strongly preferred (002) orientation perpendicular to substrate surface whatever the thickness is. The crystallite size was calculated by Williamson-Hall method, while it increases as the film thickness increased. The lattice stress is mainly caused by the growth process. Hall measurements revealed electrical parameter very dependent upon thickness when the thickness of ZAO film is lower than 700 nm. The resistivity decreased and the carrier concentration and Hall mobility increases as the film thickness increased. When film thickness becomes larger, only a little change in the above properties was observed. All the films have high transmittance above 90% in visible range. Red shift of the absorption edge was observed as thickness increased. The optical energy bandgap decreased from 3.41eV to 3.30 eV with the increase of film thickness.

Film thickness effect on texture and residual stress sign transition in sputtered TiN thin films

2017 ◽  
Vol 43 (15) ◽  
pp. 11992-11997 ◽  
Author(s):  
Yeting Xi ◽  
Kewei Gao ◽  
Xiaolu Pang ◽  
Huisheng Yang ◽  
Xiaotao Xiong ◽  
...  
Keyword(s):  
Thin Films ◽  
Residual Stress ◽  
Film Thickness ◽  
Thickness Effect ◽  
Tin Thin Films

Film Thickness Effect on Tensile Properties and Microstructures of Submicron Aluminum Thin Films on Polyimide

1996 ◽  
Vol 436 ◽  
Author(s):  
Y. S. Kang ◽  
P. S. Ho ◽  
R. Knipe ◽  
J. Tregilgas
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Film Thickness ◽  
Metal Film ◽  
Tensile Force ◽  
Thickness Effect ◽  
Published Data ◽  
Free Standing ◽  
Aluminum Films ◽  
Flexible Polymer

AbstractThe mechanical behavior of the metal film on a polymer substrate becomes an important issue in microelectronics metallization. The metal/polymer structure is also useful to investigate the deformation behavior of very thin free-standing metal film since the flexible polymer serves as a deformable substrate. The tensile force-elongation curves have been measured using a microtensile tester for aluminum thin films, deposited on a PMDA-ODA polyimide film, in the thickness range from 60 rum to 480 nm. The stress-strain curves for aluminum films were constructed by subtracting these curves with polyimide curves measured separately. Tensile strength increases linearly with decreasing film thickness from 196 MPa to 408 MPa within the film thickness range studied. This is in good agreement with the published data for free-standing aluminum films in the same thickness range. The measured Young's modulus is lower than the bulk modulus and exhibits no systematic dependence on the film thickness. The microstructures of aluminum films have been examined using a transmission electron microscope (TEM). These films posses the (111)-textured columnar grain structures. Grain sizes exhibit log-normal distributions and the mean grain size increases monotonically with the film thickness. An attempt is made to evaluate the effect of film thickness and grain size on the strength of aluminum thin film and the result is discussed.

Rheological Properties of Multi-Block Associative Polyelectrolytes Obtained by Nitroxide-Mediated Solution Polymerization

2014 ◽  
Vol 1613 ◽  
pp. 143-149
Author(s):  
Alejandro Coronado ◽  
Areli I. Velazquez ◽  
Enrique J. Jiménez
Keyword(s):  
Rheological Properties ◽  
Creep Compliance ◽  
Viscoelastic Behavior ◽  
Degree Of Polymerization ◽  
Shear Rates ◽  
Linear Response Regime ◽  
Copolymer Structure ◽  
Rheological Experiments ◽  
Polymer Bearing ◽  
Low Shear

ABSTRACTA multi-block associative polyelectrolyte based on poly(methacrylic acid-ra-styrene) [MAA-S] and poly(octadecyl methacrylate) [ODMA] was synthesized through stepwise nitroxide-mediated solution polymerizations. The obtained polymer has a heptablock copolymer structure, alternating MAA-S as hydrophilic blocks (theoretical degree of polymerization [DPT] of 250), and ODMA as hydrophobic blocks (DPT = 15). Rheological properties, in the linear-response regime, of aqueous solutions (polymer content = 1.5 wt.%) were studied as a function of the amount of blocks on the polymer using steady-shear and creep-compliance experiments. Rheological experiments demonstrate that the viscoelastic behavior of the polymer bearing an ODMA block in terminal position greatly differs from that of the polymer with MAA-S block terminations. The former behaves as a newtonian fluid on a wider range of shear rates than the latter, which exhibit a shear-thinning behavior, even at low shear rates, independently of the molecular weight and number of blocks.

Effects of Thickness on the Responses of Piezoresponse Force Microscopy for Piezoelectric Film/Substrate Systems

2017 ◽  
Vol 84 (12) ◽  
Author(s):  
J. H. Wang ◽  
C. Q. Chen
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Empirical Formula ◽  
Piezoelectric Coefficient ◽  
Surface Displacement ◽  
Piezoresponse Force Microscopy ◽  
Thickness Effect ◽  
Image Charge ◽  
Force Microscopy ◽  
Semi Empirical

Piezoresponse force microscopy (PFM) extends the conventional nano-indentation technique and has become one of the most widely used methods to determine the properties of small scale piezoelectric materials. Its accuracy depends largely on whether a reliable analytical model for the corresponding properties is available. Based on the coupled theory and the image charge model, a rigorous analysis of the film thickness effects on the electromechanical behaviors of PFM for piezoelectric films is presented. When the film is very thick, analytical solutions for the surface displacement, electric potential, image charge, image charge distance, and effective piezoelectric coefficient are obtained. For the infinitely thin (IT) film case, the corresponding closed-form solutions are derived. When the film is of finite thickness, a single parameter semi-empirical formula agreeing well with the numerical results is proposed for the effective piezoelectric coefficient. It is found that if the film thickness effect is not taken into account, PFM can significantly underestimate the effective piezoelectric coefficient compared to the half space result. The effects of the ambient dielectric property on PFM responses are also explored. Humidity reduces the surface displacement, broadens the radial distribution peak, and greatly enlarges the image charge, resulting in reduced effective piezoelectric coefficient. The proposed semi-empirical formula is also suitable to describe the thickness effects on the effective piezoelectric coefficient of thin films in humid environment. The obtained results can be used to quantitatively interpret the PFM signals and enable the determination of intrinsic piezoelectric coefficient through PFM measurement for thin films.

Thickness Effect on Microstructure and Residual Stress of Annealed Copper Thin Films

2011 ◽  
Vol 681 ◽  
pp. 139-144 ◽  
Author(s):  
Renaud Vayrette ◽  
Christian Rivero ◽  
Sylvain Blayac ◽  
Karim Inal
Keyword(s):  
Thin Films ◽  
Residual Stress ◽  
Film Thickness ◽  
Crystallite Size ◽  
Annealing Temperature ◽  
Stress Generation ◽  
Thickness Effect ◽  
Electron Backscattered Diffraction ◽  
Electroplated Copper ◽  
Stress Models

In this work, coupled effects of thickness and annealing temperature on both microstructure and residual stress of electroplated copper thin films are studied. Microstructure is investigated by Electron Backscattered Diffraction (EBSD) and residual stress is estimated from samples curvature. All films exhibit highly twinned grains. Except for several microns films, median crystallite size grows with both film thickness and annealing temperature. Concerning residual stress, it decreases, first as the increase of film thickness, and secondly as the decrease of annealing temperature. The comparison between experiments and stress models demonstrates that the root mechanisms of residual stress generation change with annealing temperature. As well as annealing temperature, film thickness determines the level of residual stress through control of microstructure. Furthermore, EBSD investigations confirmed that the relevant microstructural length to define mechanical properties of thin copper films is the median crystallite size.

Film thickness effect on fractality of tin-doped In2O3 thin films

2015 ◽  
Vol 11 (5) ◽  
pp. 749-757 ◽  
Author(s):  
Ştefan Ţălu ◽  
Sebastian Stach ◽  
Davood Raoufi ◽  
Fayegh Hosseinpanahi
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Thickness Effect
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