Observation of Size Effect and Measurement of Mechanical Properties of Ti Thin Film by Bulge Test

This paper will discuss two different techniques to measure mechanical properties of thin film, bulge test and nano-indentation test. In the bulge test, uniform pressure applies to one side of thin film. Measurement of the membrane deflection as a function of the applied pressure allows one to determine the mechanical properties such as the elastic modulus and the residual stress. Nano-indentation measurements are accomplished by pushing the indenter tip into a sample and then withdrawing it, recording the force required as a function of position. . In this study, modified King’s model can be used to estimate the mechanical properties of the thin film in order to avoid the effect of substrates. Both techniques can be used to determine Young’s modulus or Poisson’s ratio, but in both cases knowledge of the other variables is needed. However, the mathematical relationship between the modulus and Poisson's ratio is different for the two experimental techniques. Hence, achieving agreement between the techniques means that the modulus and Poisson’s ratio and Young’s modulus of thin films can be determined with no a priori knowledge of either.

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Mechanical properties of polymer thin film measured by the bulge test

Thin Solid Films ◽

10.1016/j.tsf.2007.01.058 ◽

2007 ◽

Vol 515 (18) ◽

pp. 7222-7226 ◽

Cited By ~ 41

Author(s):

C.K. Huang ◽

W.M. Lou ◽

C.J. Tsai ◽

Tung-Chuan Wu ◽

Hung-Yi Lin

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Bulge Test ◽

Polymer Thin Film

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Analysis of the accuracy of the bulge test in determining the mechanical properties of thin films

Journal of Materials Research ◽

10.1557/jmr.1992.1553 ◽

1992 ◽

Vol 7 (6) ◽

pp. 1553-1563 ◽

Cited By ~ 201

Author(s):

Martha K. Small ◽

W.D. Nix

Keyword(s):

Thin Film ◽

Thin Films ◽

Mechanical Properties ◽

Finite Element ◽

Material Properties ◽

Deformation Behavior ◽

Initial Conditions ◽

Standard Technique ◽

Bulge Test ◽

The Finite Element Method

Since its first application to thin films in the 1950's the bulge test has become a standard technique for measuring thin film mechanical properties. While the apparatus required for the test is simple, interpretation of the data is not. Failure to recognize this fact has led to inconsistencies in the reported values of properties obtained using the bulge test. For this reason we have used the finite element method to model the deformation behavior of a thin film in a bulge test for a variety of initial conditions and material properties. In this paper we will review several of the existing models for describing the deformation behavior of a circular thin film in a bulge test, and then analyze these models in light of the finite element results. The product of this work is a set of equations and procedures for analyzing bulge test data that will improve the accuracy and reliability of this technique.

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Re-Examining the Bulge Test: Methods for Improving Accuracy and Reliability

MRS Proceedings ◽

10.1557/proc-239-257 ◽

1991 ◽

Vol 239 ◽

Cited By ~ 7

Author(s):

Martha K. Small ◽

Joost J. Vlassak ◽

William D. Nix

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Tensile Tests ◽

Test Methods ◽

Tension Test ◽

Bulge Test ◽

Test Results ◽

Bulk Materials ◽

Test Technique ◽

Improving Accuracy

ABSTRACTSince its first application to thin films in the 1950's, the bulge test has had a prominent place in the field of thin film mechanical properties. The major appeal of the technique is that it is analogous to the familiar uniaxial tension test, which is commonly applied to bulk materials. At the same time, it avoids the sample tearing and alignment problems associated with micro-tensile tests. Unfortunately, bulge test results have been sometimes controversial and difficult to reproduce. In this paper we address possible causes for mese inconsistencies and describe a method by which the bulge test technique can be made to produce accurate and reliable results.

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Nanoindentation study of size effect and loading rate effect on mechanical properties of a thin film metallic glass Cu49.3Zr50.7

Physica B Condensed Matter ◽

10.1016/j.physb.2011.10.050 ◽

2012 ◽

Vol 407 (3) ◽

pp. 340-346 ◽

Cited By ~ 25

Author(s):

Jian-Jun Pang ◽

Ming-Jen Tan ◽

K.M. Liew ◽

Christopher Shearwood

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Metallic Glass ◽

Size Effect ◽

Loading Rate ◽

Rate Effect

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Measurement of Effects of Different Substrates on the Mechanical Properties of Submicron Titanium Nickel Shape Memory Alloy Thin Film Using the Bulge Test

Micromachines ◽

10.3390/mi12010085 ◽

2021 ◽

Vol 12 (1) ◽

pp. 85

Author(s):

Nhat Minh Dang ◽

Zhao-Ying Wang ◽

Ti-Yuan Wu ◽

Tra Anh Khoa Nguyen ◽

Ming-Tzer Lin

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Thermal Cycling ◽

Shape Memory ◽

Physical Vapor Deposition ◽

Phase Changes ◽

Bulge Test ◽

Alloy Thin Film ◽

Adhesion Layer ◽

Titanium Nickel

This study investigated the effects of different substrates on the mechanical properties of Ti-60at%Ni shape memory alloys (SMA). Two types of samples were prepared for this experiment: (1) a Ti-60at%Ni deposited on SiNx, and (2) a Ti-60at%Ni deposited on SiNx/Cr; both had a 600 nm thick film of Ti-60at%Ni. Deposition was done using the physical vapor deposition (PVD) process, and the microstructural changes and crystallization phase changes were observed through scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that the TiNi thin film with a Cr adhesion layer had better mechanical properties. The bulge test showed that TiNi thin film with a Cr adhesion had a higher Young’s modulus and lower residual stress. From the thermal cycling experiment, it was found that the Cr adhesion layer buffered the mismatch between TiNi and SiNx. Additionally, the thermal cycling test was also used to measure the thermal expansion coefficient of the films, and the fatigue test showed that the Cr layer significantly improved the fatigue resistance of the TiNi film.

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Novel technique for measuring the mechanical properties of porous materials by nanoindentation

Journal of Materials Research ◽

10.1557/jmr.2006.0088 ◽

2006 ◽

Vol 21 (3) ◽

pp. 715-724 ◽

Cited By ~ 79

Author(s):

Xi Chen ◽

Yong Xiang ◽

Joost J. Vlassak

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Porous Materials ◽

Bulge Test ◽

Indentation Hardness ◽

Plastic Properties ◽

Dielectric Thin Film ◽

Porous Thin Films ◽

A New Technique ◽

Low Permittivity

A new technique for measuring the elastic-plastic properties of porous thin films by means of nanoindentation is proposed. The effects of porosity on indentation hardness and modulus are investigated through finite element analyses based on the Gurson model for plastic deformation of ductile porous materials. Intrinsic mechanical properties of the thin film are obtained by eliminating both substrate and densification effects. The technique is applied to the special case of a porous, low-permittivity dielectric thin film. The results are in good agreement with those obtained independently using the plane-strain bulge test.

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Microstructural and fractographic characterization of B4C-Al cermets tested under dynamic and static loading

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154780 ◽

1989 ◽

Vol 47 ◽

pp. 562-563

Author(s):

Gyeung Ho Kim ◽

Mehmet Sarikaya ◽

D. L. Milius ◽

I. A. Aksay

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Fracture Toughness ◽

Static Loading ◽

Carbon Deposition ◽

Full Density ◽

Unique Combination ◽

Strong Component ◽

Reaction Products

Cermets are designed to optimize the mechanical properties of ceramics (hard and strong component) and metals (ductile and tough component) into one system. However, the processing of such systems is a problem in obtaining fully dense composite without deleterious reaction products. In the lightweight (2.65 g/cc) B4C-Al cermet, many of the processing problems have been circumvented. It is now possible to process fully dense B4C-Al cermet with tailored microstructures and achieve unique combination of mechanical properties (fracture strength of over 600 MPa and fracture toughness of 12 MPa-m1/2). In this paper, microstructure and fractography of B4C-Al cermets, tested under dynamic and static loading conditions, are described.The cermet is prepared by infiltration of Al at 1150°C into partially sintered B4C compact under vacuum to full density. Fracture surface replicas were prepared by using cellulose acetate and thin-film carbon deposition. Samples were observed with a Philips 3000 at 100 kV.

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Experimental Study on the Mechanical Properties and Compression Size Effect of Recycled Aggregate Concrete

Materials ◽

10.3390/ma14092323 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2323

Author(s):

Yubing Du ◽

Zhiqing Zhao ◽

Qiang Xiao ◽

Feiting Shi ◽

Jianming Yang ◽

...

Keyword(s):

Mechanical Properties ◽

Size Effect ◽

Compressive Stress ◽

Failure Modes ◽

Recycled Concrete ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Aggregate Concrete ◽

Substitution Ratio ◽

The Impact

To explore the basic mechanical properties and size effects of recycled aggregate concrete (RAC) with different substitution ratios of coarse recycled concrete aggregates (CRCAs) to replace natural coarse aggregates (NCA), the failure modes and mechanical parameters of RAC under different loading conditions including compression, splitting tensile resistance and direct shear were compared and analyzed. The conclusions drawn are as follows: the failure mechanisms of concrete with different substitution ratios of CRCAs are similar; with the increase in substitution ratio, the peak compressive stress and peak tensile stress of RAC decrease gradually, the splitting limit displacement decreases, and the splitting tensile modulus slightly increases; with the increase in the concrete cube’s side length, the peak compressive stress of RAC declines gradually, but the integrity after compression is gradually improved; and the increase in the substitution ratio of the recycled aggregate reduces the impact of the size effect on the peak compressive stress of RAC. Furthermore, an influence equation of the coupling effect of the substitution ratio and size effect on the peak compressive stress of RAC was quantitatively established. The research results are of great significance for the engineering application of RAC and the strength selection of RAC structure design.

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