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Flexure-based micromechanical testing machines

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Abstract

The successful design and fabrication of structures and systems at the small scale require robust methods for characterizing the mechanical behavior of materials at the same scale. In this paper we describe the design of two flexure-based micromechanical testers capable of measuring forces with an accuracy of 25 μN over a range of 1–30 N, and specimen extensions with an accuracy of 20 nm over a range of 1–5 mm. These force and displacement resolutions and ranges are required in a wide variety of material characterization applications, such as microtensile testing of micrometer-dimensioned films, foils and wires, bending of millimeter-sized beams, as well as micro-indentation. The novel feature of our machines is that they are based on the use of two compound flexures in an integrated monolithic frame: one flexure functioning as a precision guide for actuation, and the other fexure as a linear spring for force measurement. Two machines, one with a maximum load capacity of 1.5 N and the other of 30 N, have been constructed based on this concept. Details of their design, construction, and typical test results are presented in this paper.

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Abbreviations

k :

spring constant of flexure spring

E :

Young's modulus

I :

area moment of inertia of beams in flexure mechanism

L :

length of beams in flexure mechanism

δ max :

maximum allowable deflection of flexure mechanism

σ f :

strength of material of construction of flexure mechanism

S :

factor of safety

h :

width of beams in flexure mechanism perpendicular to neutral axis

F T :

total force applied by actuator

K A :

spring constant of actuator flexure

δ A :

deflection of actuation-flexure

K L :

spring constant of load-cell-flexure

δ L :

deflection of load cell flexure

δ S :

specimen elongation

K S :

instantaneous stiffness of specimen (based on its tangent modulus)

References

  1. Spearing, M., “Materials Issues in Microelectromechanical Systems,”Acta Materialia,48,179–196 (2000).

    Article  Google Scholar 

  2. Arzt, E., “Size Effects in Materials Due to Microstructural and Dimensional Constraints: A Comparative Review,”Acta Materialia,46,5611–5626 (1998).

    Article  Google Scholar 

  3. Sharma, P., Ganti, S., andBhate, N., “Effect of Surfaces on the Size-dependent Elastic State of Nano-inhomogeneities,”Applied Physics Letters,82,535–537 (2003).

    Article  Google Scholar 

  4. Ruud, J., Josell, D., Greer, A.L., andSpaepen, F., “The Elastic Moduli of Silver Thin Films Measured with a New Microtensile Tester,”MRS Symposium Proceedings,239,239–243 (1992).

    Google Scholar 

  5. Sharpe, W.N., Yuan, B., andEdwards, R.L., “A New Technique for Measuring the Mechanical Properties of Thin Films,”Journal of Microelec-tromechanical Systems,6,193–198 (1997).

    Article  Google Scholar 

  6. Read, D.T., andDally, J.W., “Strength, Ductility and Fatigue Life of Aluminum Thin Films,”The International Journal of Microcircuits and Electronic Packaging,16,313–318 (1993).

    Google Scholar 

  7. Smith, S.T. andChetwynd, D.G., Foundations of Ultraprecision Mechanism Design, Gordon and Breach, London (1992).

    Google Scholar 

  8. Jones, R.V., “Parallel and Rectilinear Spring Movements,”Journal of Scientific Instrumentation,28,38–41, (1951).

    Article  Google Scholar 

  9. Jones, R.V., “Some Parasitic Deflections in Parallel Spring Movements,”Journal of Scientific Instrumentation,33,11–15 (1956).

    Article  Google Scholar 

  10. Gudlavalleti, S.T.E., Mechanical Testing of Solid Materials at the Microscale, M.S., Thesis, MIT (2002).

  11. Kojic, N., Kojic, M., Gudlavalleti, S., andMcKinley, G., “Solvent Removal During Synthetic and Nephila Fiber Spinning,”Biomacromolecules,5 (5),1698–1707, (2004).

    Article  Google Scholar 

  12. Su, C. andAnand, L., “A New Digital Image Correlation Algorithm for Whole-field Displacement Measurement,”Singapore-MIT Alliance Symposium 2003: Innovation in Manufacturing Systems and Technology, Hardt, D., andChee Yoon Yee, eds National University of Singapore, Singapore (2003).

    Google Scholar 

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Author information

Authors and Affiliations

  1. General Electric Global Research, 1 Research Circle, 12309, Niskayuna, NY, USA

    S. Gudlavalleti (Research Enginger)

  2. Department of Mechanical Engineering, Massachusetts Institute of Technology, 02139, Cambridge, MA, USA

    B. P. Gearing (Associated with Weil, Gotshal and Manges LLP) & L. Anand (Professor)

Authors
  1. S. Gudlavalleti
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  2. B. P. Gearing
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  3. L. Anand
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Gudlavalleti, S., Gearing, B.P. & Anand, L. Flexure-based micromechanical testing machines. Experimental Mechanics 45, 412–419 (2005). https://doi.org/10.1007/BF02427988

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  • DOI: https://doi.org/10.1007/BF02427988

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