Design of surface forces apparatus for tribology studies combined with nonlinear optical spectroscopy

Journal Article · Sun Jun 01 04:00:00 EDT 1997 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.1148148· OSTI ID:509127

Frantz, P; Wolf, F; Xiao, X; Chen, Y; Bosch, S; Salmeron, M ^[1]

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1. Materials Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 (United States)

We describe the design, calibration, and performance of surface forces apparatus with the capability of illumination of the contact interface for spectroscopic investigation using optical techniques. The apparatus can be placed in the path of a Nd-YAG laser for studies of the linear response or the second harmonic and sum-frequency generation from a material confined between the two surfaces. In addition to the standard fringes of equal chromatic order technique, which we have digitized for accurate and fast analysis, the distance of separation can be measured with a fiber-optic interferometer during spectroscopic measurements (2 {Angstrom} resolution and 10 ms response time). The sample approach is accomplished through application of a motor drive, piezoelectric actuator, or electromagnetic lever deflection for variable degrees of range, sensitivity, and response time. To demonstrate the operation of the instrument, the stepwise expulsion of discrete layers of octamethylcyclotetrasiloxane from the contact is shown. Lateral forces may also be studied by using piezoelectric bimorphs to induce and direct the motion of one surface. {copyright} {ital 1997 American Institute of Physics.}

• Research Organization: Lawrence Berkeley National Laboratory
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 509127
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 6 Vol. 68; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
CALIBRATION
DESIGN
HARMONICS
INTERFEROMETERS
INTERFEROMETRY
LASER SPECTROSCOPY
LASERS
MEASURING INSTRUMENTS
MEASURING METHODS
OPTICAL SPECTROMETERS
PERFORMANCE
SURFACES
TRIBOLOGY