A multi-axis confocal rheoscope for studying shear flow of structured fluids

Lin, Neil Y. C.; McCoy, Jonathan H.; Cheng, Xiang; Leahy, Brian; Israelachvili, Jacob N.; Cohen, Itai

A multi-axis confocal rheoscope for studying shear flow of structured fluids

Type

Article

Authors

Lin, Neil Y. C.
McCoy, Jonathan H.
Cheng, Xiang
Leahy, Brian
Israelachvili, Jacob N.
Cohen, Itai

KAUST Grant Number

KUS-C1-018-02

Date

2014-03

Abstract

We present a new design for a confocal rheoscope that enables uniform uniaxial or biaxial shear. The design consists of two precisely positioned parallel plates with a gap that can be adjusted down to 2 ±0.1 μm, allowing for the exploration of confinement effects. By using our shear cell in conjunction with a biaxial force measurement device and a high-speed confocal microscope, we are able to measure the real-time biaxial stress while simultaneously imaging the material three-dimensional structure. We illustrate the importance of the instrument capabilities by discussing the applications of this instrument in current and future research topics in colloidal suspensions. © 2014 AIP Publishing LLC.

Citation

Lin NYC, McCoy JH, Cheng X, Leahy B, Israelachvili JN, et al. (2014) A multi-axis confocal rheoscope for studying shear flow of structured fluids. Review of Scientific Instruments 85: 033905. Available: http://dx.doi.org/10.1063/1.4868688.

Acknowledgements

The authors would like to acknowledge J. Mergo, T. Beatus, and Y.-W. Lin for technical help and useful discussions on apparatus design. Because this technique took years to develop many individuals contributed to its design. The original prototype was developed by I. C. in collaboration with T. G. Mason and D. A. Weitz. The current version of the multiaxis piezo actuator and uniaxial FMD were developed by J. H. M., J.N.I., and I. C., the biaxial shear protocols and FMD were developed by N.L., J.N.I, and I. C. In addition, the arduous work of developing mechanical and optical calibrations, method development, and developing operating procedures were worked on by N.L., X. C., B. L., and J. H. M. This publication was based on work supported by Award No. KUS-C1-018-02, made by King Abdullah University of Science and Technology (KAUST), the National Science Foundation (NSF) under Grant No. DMR 1056662; the (U.S.) Department of Energy (DOE), Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award No. ER46517, and in part under National Science Foundation CBET-PMP Award No. 1232666. J. H. M. was funded in part by Colby College, B. L. acknowledges the DoD, (U.S.) Air Force Office of Scientific Research (USAFOSR), National Defense Science and Engineering Graduate (NDSEG) Fellowship 32 CFR 168a. J.N.I was supported by the Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, under Award No. DE-FG02-87ER-45331, and by the National Science Foundation Grant No. CHE-1059108.