Experimental Mechanics

, Volume 31, Issue 2, pp 98–103 | Cite as

Micro-interferometry for measurement of thermal displacements at fiber/matrix interfaces

  • N. R. Sottos
  • W. R. Scott
  • R. L. McCullough


A micro-interferometric technique for measuring out-of-plane thermal displacements on a scale commensurate with the dimensions of the fiber/matrix unit cell is described. A scanning micro-interferometer is used to image surface displacements of samples containing a single-pitch-based carbon fiber embedded in an epoxy matrix. The interferometer design gives the necessary resolution to detect small changes in thermal displacements in the fiber/matrix interface region. The samples were heated electrically through the fiber to create radially symmetric temperature and displacement fields. Repeatable displacement measurements were obtained on a radial line across the interface region with an accuracy of ±25 Å. A sharp expansion of the matrix surrounding the fiber was observed with each heating. Overall, the experiments demonstrate the utility of micro-interferometry for measuring submicron displacements.


Epoxy Mechanical Engineer Fluid Dynamics Carbon Fiber Displacement Field 
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Copyright information

© Society for Experimental Mechanics, Inc. 1991

Authors and Affiliations

  • N. R. Sottos
    • 1
  • W. R. Scott
    • 2
  • R. L. McCullough
    • 3
  1. 1.216 Talbot LaboratoryUniversity of IllinoisUrbana
  2. 2.Naval Air Development CenterWarminster
  3. 3.Department of Chemical EngineeringUniversity of DelawareNewark

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