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Advanced ceramics and inorganic materials are critically enabling elements in devices and systems across many technology sectors, such as telecommunications and energy. The objective of this project is to determine, compile and evaluate phase equilibrium data for NIST Standard Reference Database 31.

Technical One Pagers Drafts
The data, consisting of graphical diagrams, provide equilibrium chemical and structural behaviors. NIST Standard Reference Database 31 disseminates readily accessible and searchable data electronically in partnership with the American Ceramic Society ( ACerS ).

A free demonstration CD is available upon request or can be downloaded from the website:


Impact and Customers:

Every deliberate effort to develop a new ceramic or to improve processing begins with chemical composition and the conditions (temperature, pressure) under which pure compounds and their mixtures are stable (an equilibrium phase diagram). In the absence of such information, developers must resort to trial-and-error approaches or conduct their own studies to obtain the data.

NIST ACerS Phase Equilibria Diagrams
  • 24,800 diagrams in 21 hard-copy volumes, CD-ROM versions and a new web platform; more than 60,000 units sold worldwide
  • About 1,000 new diagrams released annually
  • Annual sales of $200,000 to $300,000
  • 300 to 400 website hits per month at
  • 40 to 60 downloads per month of demonstration version from NIST Standard Reference Data website
  • Customers: Materials developers in industry, government and academia


NIST Standard Reference Database 31, published from 1964 to 1992 as the well-known Phase Diagrams for Ceramists "blue books," is the result of a long-standing collaboration between NIST and The American Ceramic Society to develop and maintain a state-of-the-art database of critically evaluated phase equilibria data for industrial and academic customers. In 1992, the title was changed to the more general "Phase Equilibria Diagrams" to emphasize that the data are useful to the broader inorganic materials community. Standard Reference Database 31 serves as the only "Mapquest" database for ceramic and inorganic systems: The diagrams provide maps of the equilibrium chemical and structural behaviors exhibited by materials and provide critical starting information for the rational design of materials-processing schemes and for quality assurance efforts and optimization of the physical and chemical properties of advanced materials.

Major Accomplishments

start screen srd31 4.2
The 2012 release is the largest-ever update of Standard Reference Database 31 and includes 900 new figures with more than 1,400 new phase diagrams, in addition to all the information previously printed in the 21 hard-copy volumes of the series. The new content includes experimental and calculated data for an unprecedented range of non-organic material types, including phosphates (batteries, laser and other optoelectronic materials), chalcogenides (semiconducting sulfides, selenides and tellurides for thermoelectrics, optoelectronics and photovoltaics), pnictides (nitrides, phosphides, arsenides and antimonides for bandgap-engineered optical materials, electron-transport devices, sensors, detectors, photovoltaics and thermoelectrics), halides (nuclear applications, scintillation detectors), and oxide/metal+oxide systems (electrode processing, catalysis, electroceramics, magneto-resistors, thermistors, capacitors, nuclear fuel and waste, ionic conductors, and fuel-cell electrolytes).

By way of illustration, if one searches for phase diagrams containing: SrO, TiO2 and Nb2O5, we uncover Fig. 11446, a phase diagram for the ternary system (below). An extensive commentary details the experimental data presented within the diagram. This is just one example of the more than 24,000 diagrams present in SRD 31.

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Created October 24, 2008, Updated November 29, 2017