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Thermodynamics

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

Projects and Programs

Platform for Realizing Integrated Molecule Experiments (PRIME)

Ongoing
Blackbodies realize a clear relationship between radiated power and temperature through Planck’s law. While a reliable instrument for temperature and power calibrations, blackbodies are afflicted with a plethora of systematics (e.g., non-ideal emissivity, propagation loss, temperature gradients

Reliable Vaccine Storage

Completed
Our group examines best practices for the storage and monitoring of vaccines in partnership with the Centers for Disease Control and Prevention’s (CDC) Vaccine Supply and Assurance Branch. Vaccines are highly temperature sensitive, and inappropriate storage conditions can render them ineffective

Flow Metering and Properties for Semiconductor Process Gases

Ongoing
A type of flow meter called a mass flow controller (MFC) is used to regulate gas flow in order to produce the desired structures during chip fabrication. As semiconductor manufacturing advances, the requirements on MFC performance are increasingly strict: any process variation can reduce device

Acoustic Thermometry

Completed
Data from the NIST acoustic thermometer will form an improved basis for the equations used with platinum resistance thermometry, which is the primary mechanism to disseminate accurate temperature standards. Objective: To obtain measurements of thermodynamic temperature in the range between 273 K and

Publications

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 directly

Vacuum Gauges

Most calibrations of vacuum gauges are based on a known gas flow rate that is generated by one of two flow meters that operate at constant pressure. The "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

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

Awards