Strain and Stress Distribution in Vickers Indentation of Coated Materials

2006 ◽  
Vol 514-516 ◽  
pp. 1472-1476
Author(s):  
Jorge M. Antunes ◽  
Nataliya A. Sakharova ◽  
José Valdemar Fernandes ◽  
Luís Filipe Menezes
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Numerical Simulation ◽  
Young’S Modulus ◽  
Indentation Depth ◽  
Young's Modulus ◽  
Three Dimensional ◽  
Depth Sensing ◽  
Coated Materials ◽  
Film Substrate

Depth sensing indentation equipment allows the mechanical properties of thin films to be easily determined, particularly the hardness and Young’s modulus. In order to minimize the influence of the substrate on the measured properties, the indentation depth must be limited to a small fraction of the film’s thickness. However, for very thin films, the determination of the contribution of the substrate and the film to the measured mechanical properties becomes a hard task, because both deform plastically. The numerical simulation of ultramicrohardness tests can be a helpful tool towards better understanding of the influence of the parameters involved in the mechanical characterization of thin films. For this purpose, a three-dimensional numerical simulation home code, HAFILM, was used to simulate ultramicrohardness tests on coated substrates. Materials with different Young’s modulus film/substrate ratios were tested. Analyses of strain and stress distributions for several indentation depth values were performed, in order to clarify the composite behaviour.

Fluctuation Mechanism of Mechanical Properties of Electroplated-Copper Thin Films Used for Three Dimensional Electronic Modules

2007 ◽  
Vol 353-358 ◽  
pp. 2954-2957 ◽  
Author(s):  
Hideo Miura ◽  
Kazuhiko Sakutani ◽  
Kinji Tamakawa
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Bulk Material ◽  
Three Dimensional ◽  
Columnar Structure ◽  
Columnar Grains ◽  
Plane Distribution ◽  
Electroplated Copper

The mechanical properties of copper thin films deposited by sputtering and electroplating were compared using tensile test and nano-indentation. Both the Young’s modulus and tensile strength of the films were found to vary drastically depending on the microstructure of the deposited films. The Young’s modulus of the sputtered film was almost same as that of bulk material. However, the Young’s modulus of the electroplated thin film was about a fourth of that of bulk material. The micro structure of the electroplated film was polycrystalline and a columnar structure with a diameter of a few hundred-micron. The strength of the grain boundaries of the columnar grains seemed to be rather week. In addition, there was a sharp distribution of Young’s modulus along the thickness direction of the film. Though the modulus near the surface of the film was close to that of bulk material, it decreased drastically to about a fourth within the depth of about 1 micron. There was also a plane distribution of Young’s modulus near the surface of the film.

scholarly journals Multimodal Surface Instabilities in Curved Film–Substrate Structures

2017 ◽  
Vol 84 (8) ◽  
Author(s):  
Ruike Zhao ◽  
Xuanhe Zhao
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Numerical Simulation ◽  
Period Doubling ◽  
Tubular Structures ◽  
Modulus Ratio ◽  
Future Design ◽  
Mismatch Strain ◽  
Curved Structures ◽  
Film Substrate

Structures of thin films bonded on thick substrates are abundant in biological systems and engineering applications. Mismatch strains due to expansion of the films or shrinkage of the substrates can induce various modes of surface instabilities such as wrinkling, creasing, period doubling, folding, ridging, and delamination. In many cases, the film–substrate structures are not flat but curved. While it is known that the surface instabilities can be controlled by film–substrate mechanical properties, adhesion and mismatch strain, effects of the structures’ curvature on multiple modes of instabilities have not been well understood. In this paper, we provide a systematic study on the formation of multimodal surface instabilities on film–substrate tubular structures with different curvatures through combined theoretical analysis and numerical simulation. We first introduce a method to quantitatively categorize various instability patterns by analyzing their wave frequencies using fast Fourier transform (FFT). We show that the curved film–substrate structures delay the critical mismatch strain for wrinkling when the system modulus ratio between the film and substrate is relatively large, compared with flat ones with otherwise the same properties. In addition, concave structures promote creasing and folding, and suppress ridging. On the contrary, convex structures promote ridging and suppress creasing and folding. A set of phase diagrams are calculated to guide future design and analysis of multimodal surface instabilities in curved structures.

scholarly journals Influence of three-dimensional nanoparticle branching on the Young’s modulus of nanocomposites: Effect of interface orientation

2015 ◽  
Vol 112 (21) ◽  
pp. 6533-6538 ◽  
Author(s):  
Shilpa N. Raja ◽  
Andrew C. K. Olson ◽  
Aditya Limaye ◽  
Kari Thorkelsson ◽  
Andrew Luong ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Three Dimensional ◽  
Elastic Stiffness ◽  
Limited Attention ◽  
Unexpected Finding ◽  
Covalent Bonds ◽  
Lattice Spring Model ◽  
Common Block

With the availability of nanoparticles with controlled size and shape, there has been renewed interest in the mechanical properties of polymer/nanoparticle blends. Despite the large number of theoretical studies, the effect of branching for nanofillers tens of nanometers in size on the elastic stiffness of these composite materials has received limited attention. Here, we examine the Young's modulus of nanocomposites based on a common block copolymer (BCP) blended with linear nanorods and nanoscale tetrapod Quantum Dots (tQDs), in electrospun fibers and thin films. We use a phenomenological lattice spring model (LSM) as a guide in understanding the changes in the Young's modulus of such composites as a function of filler shape. Reasonable agreement is achieved between the LSM and the experimental results for both nanoparticle shapes—with only a few key physical assumptions in both films and fibers—providing insight into the design of new nanocomposites and assisting in the development of a qualitative mechanistic understanding of their properties. The tQDs impart the greatest improvements, enhancing the Young's modulus by a factor of 2.5 at 20 wt.%. This is 1.5 times higher than identical composites containing nanorods. An unexpected finding from the simulations is that both the orientation of the nanoscale filler and the orientation of X-type covalent bonds at the nanoparticle-ligand interface are important for optimizing the mechanical properties of the nanocomposites. The tQD provides an orientational optimization of the interfacial and filler bonds arising from its three-dimensional branched shape unseen before in nanocomposites with inorganic nanofillers.

Young's modulus of thin films using depth-sensing indentation

2010 ◽  
Vol 90 (1) ◽  
pp. 9-22 ◽  
Author(s):  
J.V. Fernandes ◽  
J.M. Antunes ◽  
N.A. Sakharova ◽  
M.C. Oliveira ◽  
L.F. Menezes
Keyword(s):  
Thin Films ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Depth Sensing

Possible Artefacts in Measurement of Hardness and Elastic Modulus on Superhard Coatings and the Verification of the Correctness of the Data

2002 ◽  
Vol 750 ◽  
Author(s):  
S. Veprek ◽  
S. Mukherjee ◽  
P. Karvankova ◽  
H.-D. Männling ◽  
J. L. He ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Young’S Modulus ◽  
Indentation Depth ◽  
Brillouin Scattering ◽  
Young's Modulus ◽  
Linear Extrapolation ◽  
Depth Sensing ◽  
Vibrating Reed ◽  
Superhard Coatings ◽  
Scanning Electron

ABSTRACTMeasurements of the hardness and Young's modulus of superhard coatings (HV≥40 GPa) by means of automated load-depth-sensing indentation technique can be subject to a number of errors that are discussed and exemplified here. Only load-independent values of hardness for loads larger than 30–50 mN can be considered reliable when the technique of Doerner and Nix (linear extrapolation of the unloading curve) is used to determine the corrected indentation depth. The results are compared with values of Vickers hardness calculated from the contact area of the remaining plastic deformation which was measured by means of calibrated scanning electron microscope. The values of Young's modulus obtained from the indentation are close to the zero-pressure shear modulus of the coatings as measured by means of Vibrating Reed and surface Brillouin scattering techniques.

Nanoindentation Measurements on Low-k Porous Silica Thin Films Spin Coated on Silicon Substrates

2003 ◽  
Vol 125 (4) ◽  
pp. 361-367 ◽  
Author(s):  
Xiaoqin Huang ◽  
Assimina A. Pelegri
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Mechanical Properties ◽  
Young’S Modulus ◽  
Microelectromechanical Systems ◽  
Young's Modulus ◽  
Porous Silica ◽  
Silicon Substrates ◽  
Silica Thin Films ◽  
Low K

MEMS (MicroElectroMechanical Systems) are composed of thin films and composite nanomaterials. Although the mechanical properties of their constituent materials play an important role in controlling their quality, reliability, and lifetime, they are often found to be different from their bulk counterparts. In this paper, low-k porous silica thin films spin coated on silicon substrates are studied. The roughness of spin-on coated porous silica films is analyzed with in-situ imaging and their mechanical properties are determined using nanoindentation. A Berkovich type nanoindenter, of a 142.3 deg total included angle, is used and continuous measurements of force and displacements are acquired. It is shown, that the measured results of hardness and Young’s modulus of these films depend on penetration depth. Furthermore, the film’s mechanical properties are influenced by the properties of the substrate, and the reproduction of the force versus displacement curves depends on the quality of the thin film. The hardness of the studied low-k spin coated silica thin film is measured as 0.35∼0.41 GPa and the Young’s modulus is determined as 2.74∼2.94 GPa.

Effects of the Substrate on the Determination of SEBS Thin Film Mechanical Properties by Nanoindentation

2006 ◽  
Vol 315-316 ◽  
pp. 766-769
Author(s):  
Yong Zhi Cao ◽  
Ying Chun Liang ◽  
Shen Dong ◽  
T. Sun ◽  
Bo Wang
Keyword(s):  
Thin Film ◽  
Mechanical Properties ◽  
Polymer Film ◽  
Young’S Modulus ◽  
Penetration Depth ◽  
Young's Modulus ◽  
Polymer Film Substrate ◽  
Film Substrate ◽  
Composite Hardness

In order to investigate nanoindentation data of polymer film-substrate systems and to learn more about the mechanical properties of polymer film-substrate systems, SEBS (styreneethylene/ butylene-styrene) triblock copolymer thin film on different substrate systems have been tested with a systematic variation in penetration depth and substrate characteristics. Nanoindentation experiments were performed using a Hysitron TriboIndenter with a Berkvoich tip. The resulting data were analyzed in terms of load-displacement curves and various comparative parameters, such as hardness and Young’s modulus. The results obtained by the Oliver and Pharr method show how the composite hardness and Young’s modulus are different for different substrates and different penetration depth.

Mechanical Properties of Poly 3C-SiC Thin Films According to Carrier Gas (H2) Concentration

2008 ◽  
Vol 600-603 ◽  
pp. 867-870
Author(s):  
Gwiy Sang Chung ◽  
Ki Bong Han
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Mechanical Properties ◽  
Surface Roughness ◽  
Atomic Force Microscope ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Carrier Gas ◽  
Nano Indentation ◽  
Atomic Force

This paper presents the mechanical properties of 3C-SiC thin film according to 0, 7, and 10 % carrier gas (H2) concentrations using Nano-Indentation. When carrier gas (H2) concentration was 10 %, it has been proved that the mechanical properties, Young’s Modulus and Hardness, of 3C-SiC are the best of them. In the case of 10 % carrier gas (H2) concentration, Young’s Modulus and Hardness were obtained as 367 GPa and 36 GPa, respectively. When the surface roughness according to carrier gas (H2) concentrations was investigated by AFM (atomic force microscope), when carrier gas (H2) concentration was 10 %, the roughness of 3C-SiC thin was 9.92 nm, which is also the best of them. Therefore, in order to apply poly 3C-SiC thin films to MEMS applications, carrier gas (H2) concentration’s rate should increase to obtain better mechanical properties and surface roughness.

Measurement of Mechanical Properties for Thin Film Using Visual Image Tracing Method

2007 ◽  
Vol 124-126 ◽  
pp. 1701-1704 ◽  
Author(s):  
Sang Joo Lee ◽  
Seung Woo Han ◽  
Jae Hyun Kim ◽  
Hak Joo Lee
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Mechanical Properties ◽  
Young’S Modulus ◽  
Measurement System ◽  
Strain Measurement ◽  
Poisson’S Ratio ◽  
Young's Modulus ◽  
Visual Image ◽  
Poisson's Ratio

It is quite difficult to accurately measure the mechanical properties of thin films. Currently, there are several methods (or application) available for measuring mechanical properties of thin films. Their properties, however, have been determined by indirect methods such as cantilever beam test and diaphragm bulge test. This paper reports the efforts to develop a direct strain measurement system for micro/nano scale thin film materials. The proposed solution is the Visual Image Tracing (VIT) strain measurement system coupled with a micro tensile testing unit, which consists of a piezoelectric actuator, load cell, microscope and CCD cameras. The advantage of this system is the ability to monitor the real time images of specimen during the test in order to determine its Young’s modulus and Poisson’s ratio at the same time. Stress-strain curve, Young’s modulus, yield strength and Poisson’s ratio of copper thin film measured using VIT system are presented.

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