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Prices are Down, Value is Up: The Newly Expanded ACerS-NIST Database

Typical phase equilibria diagram developed at NIST

Typical phase equilibria diagram developed at NIST, this one for a combination of titanium dioxide and barium oxide. Discovery of ceramics processed in the narrow region indicated by the cross-hatched section in yellow was essential for operation of the first cell phones.

Credit: NIST

One of the most influential collections of materials data at the National Institute of Standards and Technology (NIST) is now not only bigger than ever but also—thanks to a 68 percent price drop—more affordable than ever. Under a new agreement with its partner, the American Ceramic Society (ACerS), NIST is now offering single-user licenses to the ACerS-NIST Phase Equilibria Diagrams database for $950, down from $2,995.

Many of the high-tech materials that make modern technology possible are inorganic compounds—carefully formulated and processed combinations of two or more starting materials. Both the formulation and the processing conditions—temperature especially—are critical to the difference between an ordinary ceramic and one that is, say, a high-temperature superconductor. Phase equilibria diagrams tell you which is which. Painstakingly developed from masses of data and models, the diagrams tell the engineer what sorts of compounds and crystal structures will result from mixing a set of starting materials in given ratios at a given temperature.

Often, these conditions fall within very narrow limits. Phase diagram data were essential, for example, in the development of a durable material now used worldwide in more than 500 million catalytic converters to control emissions from cars and trucks. They are an essential tool for designing new materials for an astonishing breadth of modern technology, including batteries, lasers, optoelectronics, sensors, fuel cells, semiconductors, protective coatings, telecommunications devices and industrial chemical catalysts. Phase diagrams are not only vital to understanding the behavior of ceramics and metal alloys; they are also essential for manufacturing the materials reproducibly, effectively and economically.

The Phase Equilibria Diagrams database dates to a 1933 collaboration between researchers at NIST and ACerS who put together the first compilation of 178 phase diagrams. Over the years, the collaboration continued and the database expanded, eventually moving from printed collections to a computerized database. The newly released version (3.4) has approximately 24,800 diagrams, including 892 new entries with approximately 1,400 new diagrams.

As a result of a new agreement with ACerS, NIST is now able to offer the ACerS-NIST Phase Equilibria Diagrams database on CDROM (NIST Standard Reference Database 31) at dramatic price reductions.

A free demonstration CDROM, which includes a comprehensive cumulative index for the entire database, is available upon request or can be downloaded, along with ordering and pricing information, from the NIST website.

Released July 11, 2012, Updated February 1, 2023