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Thermodynamics

Overview

Thermodynamics research at NIST helps our industrial and scientific partners develop more efficient and reliable processes by improving our understanding of how the arrangement of matter and energy impact the properties of physical and chemical systems.

Thermodymic Data Included in Phase-Based Data Repository

MGI-Logo

An essential part of the MGI is the development of phase-based data repository. Phase-based data are important for many applications, including the development of CALPHAD-based multicomponent databases. The phase-based data include zero-dimensional, one-dimensional, two-dimensional, and three-dimensional data. Examples of some of the phase-data included are phase transformation temperatures (e.g. melting, solidus, solvus), lattice parameters, thermal expansion, elastic constants, and diffusion coefficients and compositions profiles. These data are reported as functions of composition, temperature and/or pressure.

This repository consists of three data sources:

  • Curated experimental and computational multicomponent alloy data in support of the development Co-based superalloys. Currently the data are focus on diffusion data and transition temperatures. These data are curated using the NIST Materials Data Curation System. This collection is being developed in conjunction with CHiMaD.
  • Thermodynamic Research Center Data provides access to thermophysical property data with a focus on unary, binary, and ternary metal systems through a free online web application and associated API. All data are from original experimental publications and include full provenance and critically evaluated uncertainty.
  • Self diffusion and impurity diffusion coefficient data (experimental and computational) are searchable via the periodic table.

News and Updates

Sounding Out a New Way to Measure Gas Flow

Researchers at NIST have developed a new — and sound — way to accurately measure the rate at which gas flows in and out of a vessel. The technique, which uses

Reliable Flow for Chip Makers

Researchers at the National Institute of Standards and Technology (NIST) have begun an ambitious project to attack a vexing problem in the semiconductor

Projects and Programs

Reliable Vaccine Storage

Completed
We study provider-level vaccine storage and temperature monitoring methods to develop best practice guidance for public health audiences.

Fixed Point Development : Non-Metals

Ongoing
We are developing new fixed points and new maintenance systems for use with Standard Platinum Resistance Thermometers (SPRTs) below the triple point of water

Publications

Ab initio Calculation of Fluid Properties for Precision Metrology

Author(s)
Giovanni Garberoglio, Christof Gaiser, Roberto Maria Gavioso, Allan H. Harvey, Robert Hellmann, Bogumil Jeziorski, Karsten Meier, Michael R. Moldover, Laurent Pitre, Krzysztof Szalewicz, Robin Underwood
Recent advances regarding the interplay between ab initio calculations and metrology are reviewed, with particular emphasis on gas-based techniques used for

Tools and Instruments

Leak Artifacts

Leak artifacts are calibrated in the range 1 x 10 -6 to 1 x 10 -13 mol/s (2 x 10 -2 to 2 x 10 -9 std. cm 3 /s at 0 °C). The calibration can be performed

Piston gauges and pressure transducers

Piston gauges are used to calibrate customer piston gauges and pressure sensing devices. Piston gauges are calibrated via a direct comparison to another piston

Low Pressure Gauges

NIST has developed best-in-the-world primary standard pressure measurement capabilities for pressures spanning the range of 0.01 Pa to 360 kPa through the

Awards