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Search Publications by: Jon R. Pratt (Fed)

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Displaying 51 - 75 of 115

Methods for transferring the SI unit of force from millinewtons to piconewtons

June 1, 2009
Author(s)
Gordon A. Shaw, Koo-Hyun Chung, Douglas T. Smith, Jon R. Pratt
The establishment of standards for small force measurement requires a link to an absolute measurement of force traceable to the international system of units (SI). To this end, a host of different means are being employed by the NIST small force

Accurate Picometers for DC and Low-Frequency Displacement Measurement

April 6, 2009
Author(s)
Jon R. Pratt, Douglas T. Smith, Lowell Howard
We have developed a fiber-optic interferometer optimized for best performance in the frequency range from DC to 1 kHz, with displacement linearity of 1 % over a range of 25 nm, and noise-limited resolution of 2 pm [1]. The interferometer uses a tunable

2nd Annual Tri-National Workshop on Standards for Nanotechnology - (NIST presentations)

December 10, 2008
Author(s)
Ronald G. Dixson, Jon R. Pratt, Vincent A. Hackley, James E. Potzick, Richard A. Allen, Ndubuisi G. Orji, Michael T. Postek, Herbert S. Bennett, Theodore V. Vorburger, Jeffrey A. Fagan, Robert L. Watters
A new era of cooperation between North American National Measurement Institutes (NMIs) was ushered by the National Research Council of Canada Institute for National Measurement Standards (NRC-INMS) on February 7, 2007 when the first Tri-National workshop

Comparison of NIST SI Force Scale to NPL SI Mass Scale

October 19, 2008
Author(s)
Christopher W. Jones, John A. Kramar, Stuart Davidson, Richard Leach, Jon R. Pratt
Small masses in the 1.0 mg to 0.1 mg range were developed and calibrated at NPL with traceability to the IPK. These masses were transported to NIST at Gaithersburg and used as deadweights on the NIST electrostatic force balance, to facilitate a mass-force

A New Microdevice for SI-Traceable Forces in Atomic Force Microscopy

June 2, 2008
Author(s)
Gregory W. Vogl, Jason J. Gorman, Gordon A. Shaw, Jon R. Pratt
A new self-excited micro-oscillator is proposed as a velocity standard for dissemination of nanoNewton-level forces that are traceable to the International System of Units (SI). The microfabricated oscillator is top-coated with magnetic thin films and

Spring constant calibration of AFM cantilevers with a piezosensor transfer standard

September 24, 2007
Author(s)
Eric Langlois, Gordon A. Shaw, John A. Kramar, Jon R. Pratt, Donna C. Hurley
We describe a method to calibrate the spring constants of cantilevers for atomic force microscopy (AFM). The method makes use of a piezosensor comprised of a piezoresistive cantilever and accompanying electronics. The piezosensor was calibrated before use

Direct Electrostatic Calibration of Hybrid Sensors for Small Force Measurement

June 4, 2007
Author(s)
Koo-Hyun Chung, Gordon A. Shaw, Jon R. Pratt
The measurement of forces from piconewtons to millinewtons is an area of interest from both an applied and pure research standpoint, however creating a link between small forces and the International System of Units (SI) has been difficult. In this work, a

Traceable Micro-Force Sensor for Instrumented Indentation Calibration

April 10, 2007
Author(s)
Douglas T. Smith, Gordon A. Shaw, R M. Seugling, D Xiang, Jon R. Pratt
Instrumented indentation testing (IIT), commonly referred to as nanoindentation when small forces are used, is a popular technique for determining the mechanical properties of small volumes of material. Sample preparation is relatively easy, usually

A Piezoresistive Cantilever Force Sensor for Direct AFM Force Calibration

April 8, 2007
Author(s)
Jon R. Pratt, John A. Kramar, Gordon A. Shaw, Douglas T. Smith, John M. Moreland
We describe the design, fabrication, and calibration testing of a new piezoresistive cantilever force sensor suitable for the force calibration of atomic force microscopes in a range between tens of nanonewtons to hundreds of micronewtons. The sensor is

Traceable Micro-Force Calibration for Instrumented Indentation Testing

February 13, 2007
Author(s)
Douglas T. Smith, Gordon A. Shaw, Richard Seugling, Jon R. Pratt, Dan Xiang
We describe the development, performance and application of an accurate SI-traceable force calibration and verification system for potential use in the field calibration of commercial instrumented indentation testing (IIT) instruments. The system consists

Prototype Cantilevers for SI Traceable NanoNewton Force Calibration

September 20, 2006
Author(s)
Richard S. Gates, Jon R. Pratt
A series of extremely uniform prototype reference cantilevers has been created that can be used to calibrate the spring constants of atomic force microscope (AFM) cantilevers and other micromechanical structures. By utilizing optimal combinations of

Prototype Cantilevers for SI-Traceable NanoNewton Force Calibration

September 20, 2006
Author(s)
Richard S. Gates, Jon R. Pratt
A series of extremely uniform prototype reference cantilevers have been created that can be used to calibrate the spring constants of atomic force microscope (AFM) cantilevers and other micromechanical structures. By utilizing optimal combinations of

New reference standards and artifacts for nanoscale physical property characterization

July 1, 2006
Author(s)
Jon R. Pratt, John A. Kramar, Gordon Shaw, Richard Gates, Paul Rice, John M. Moreland
This paper provides an overview of calibration artifacts being developed at the National Institute of Standards and Technology (NIST) that are intended to aid the accurate determination of nanoscale physical properties across a broad range of applications

Force Calibration Via Electrostatics

January 1, 2006
Author(s)
Jon R. Pratt, John A. Kramar, Gordon A. Shaw, Lee Kumanchik
We describe the electrical and length measurements necessary to realize micronewton forces in a fashion consistent with the International System of Units (SI). We first discuss instrumentation and procedures required to accurately characterize an

New Reference Standards and Artifacts for Nanoscale Physical Property Characterization

January 1, 2006
Author(s)
Jon R. Pratt, John A. Kramar, Gordon A. Shaw, Richard S. Gates, Paul Rice, John M. Moreland
This paper provides an overview of calibration artifacts being developed at the National Institute of Standards and Technology (NIST) that are intended to aid the accurate determination of nanoscale physical properties across a broad range of applications