0
Research Papers

Evaluation of Micro-Pillar Compression Tests for Accurate Determination of Elastic-Plastic Constitutive Relations

[+] Author and Article Information
Huiyang Fei, Amit Abraham

Mechanical and Aerospace Engineering, School for Engineering of Matter, Transport and Energy, Fulton Schools of Engineering,  Arizona State University, Tempe, AZ, 85287-8706

Nikhilesh Chawla

Mechanical and Aerospace Engineering, Materials Science and Engineering, School for Engineering of Matter, Transport and Energy, Fulton Schools of Engineering,  Arizona State University, Tempe, AZ, 85287-8706

Hanqing Jiang1

Mechanical and Aerospace Engineering, School for Engineering of Matter, Transport and Energy, Fulton Schools of Engineering,  Arizona State University, Tempe, AZ, 85287-8706hanqing.jiang@asu.edu

1

Corresponding author.

J. Appl. Mech 79(6), 061011 (Sep 17, 2012) (9 pages) doi:10.1115/1.4006767 History: Received July 31, 2011; Revised February 16, 2012; Posted May 03, 2012; Published September 17, 2012; Online September 17, 2012

The micro-pillar compression test is emerging as a novel way to measure the mechanical properties of materials. In this paper, we systematically conducted finite element analysis to evaluate the capability of using a micro-compression test to probe the mechanical properties of both elastic and plastic materials. We found that this test can provide an alternative way to accurately and robustly measure strain, and to some extent, stress. Therefore, this test can be used to measure some strain related quantities, such as strain to failure, or the stress-strain relations for plastic materials.

FIGURES IN THIS ARTICLE
<>
Copyright © 2012 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

(a) Schematic of the micro-pillar compression test, (b) schematic of focused ion beam (FIB), and (c) scanning electron microscopy (SEM) image of a micro-pillar on a single grain of Sn-Ag-Cu (SAC) alloy, with a taper angle of ∼4 deg

Grahic Jump Location
Figure 2

(a) Schematic of axisymmetric model of the micro-pillar, (b) geometry and mesh of the finite element model, and (c) the stress-strain curve for the plastic material used in this study

Grahic Jump Location
Figure 3

The deformation percentage of pillar, substrate, and indenter for (a) elastic and (b) plastic materials. For elastic material, Young’s modulus E = 50 GPa and Poisson’s ratio ν = 0.3. For plastic material, the stress-strain curve is given by Fig. 2. (c) Contours of equivalent plastic strain for a pillar subject to different pressure on top of the indenter (not shown here). The pressures are 1 MPa and 7 MPa for the left and right panels, respectively. The geometry of the micro-pillar compression in this figure is that the pillar is 3 μm in height and 0.5 μm in radius on a 50 μm × 50 μm substrate.

Grahic Jump Location
Figure 4

Indenter effect on the strain measurement. Strain error and relative strain errors of elastic pillars when the pressure is applied on (a) a diamond intender, and (b) a rigid indenter. (c) Strain errors and relative strain errors for a plastic material with stress-strain curve given by Fig. 2 as input.

Grahic Jump Location
Figure 5

Substrate size effect on the strain measurement, for (a) an elastic material with Young’s modulus 50 GPa and Poisson’s ratio 0.3, and (b) a plastic material with stress-strain curve given by Fig. 2

Grahic Jump Location
Figure 6

Aspect ratio effect on the strain measurement, for (a) an elastic material with Young’s modulus 50 GPa and Poisson’s ratio 0.3, and (b) a plastic material with stress-strain curve given by Fig. 2

Grahic Jump Location
Figure 7

Taper angle on the strain measurement, for (a) an elastic material with Young’s modulus 50 GPa and Poisson’s ratio 0.3, and (b) a plastic material with stress-strain curve given by Fig. 2

Grahic Jump Location
Figure 8

(a) Contours of pillar stress for a straight pillar (θ=0 deg) and a tapered one (θ=5 deg). The material is elastic, E = 50 GPa and ν = 0.3; the pillar geometry is 3 μm in height and 0.5 μm in top radius. The substrate size is 50 μm × 50 μm (not completely shown). (b) Taper angle effect of an elastic pillar on measuring the Young’s modulus. (c) Evaluation of different stress measurement for plastic pillars with different taper angles. (d) Taper angle effect of stress measurement on plastic pillars using Eq. 15. Black square points are stress-strain input from Fig. 2.

Grahic Jump Location
Figure 9

Aspect ratio effect of stress measurement on plastic pillar using Eq. 15. Black square points are stress-strain input from Fig. 2.

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In