Support and FAQs

Whether you need help choosing the right Phase Equilibrium Diagram Product or troubleshooting problems after your purchase, ACerS is there to give you support.  We offer the following FAQs, which should provide you the information you need.  If not, please do not hesitate to contact the following people.

Product questions and quotations

ACerS Customer Service,

Technical support

Phase support team,

Frequently Asked Questions

What is the ACerS-NIST Phase Equilibria Diagram product

The program provides 31,000 relevant, critically evaluated phase diagrams with commentaries for inorganic compounds (ceramics and glasses), including oxides, non-oxides, salts, carbides, nitrides, borides, compound semiconductors, pnictides and chalcogenides. Also included is the PED Viewer which simplifies the analysis of these complex graphs. This program is the result of a collaboration between the National Institute of Standards and Technology (NIST) and The American Ceramic Society (ACerS) that began more than 60 years ago.

The data are pertinent to a wide variety of applications and include systems of interest for renewable energy technologies (e.g. heat-storage/transfer materials, conversion phosphors, photovoltaics, molten electrolytes, advanced anode and electrolyte materials for battery applications, nuclear-reactor technology and radioactive waste recycling) and next-generation electronic, magnetic, photonic, and optoelectronic devices (e.g. proton conductors, luminescent hosts, solid-electrolyte membranes, liquid-crystal displays, electrochemical sensors, magnetic sensors, actuators, capacitors, transducers, thermoelectric elements, memory elements, fluorescent LED materials, laser hosts, optical fibers, magnetic refrigerators, thermoluminescent elements). The collection includes data for material systems of interest in other diverse applications such as antibacterial agents, bio-compatible ceramics, cutting materials, fluxes for metallurgical processing/electrolytic refining, improved cement, ceramic filters, semiconductor manufacturing, catalysts and photo-catalysts, thermal‐barrier coatings, pigments, and fuel cells.

What is new with Version 5.1?

The Version 5.1 content-update provides Volume 25 with 157 new Figures and 663 new diagrams – 117 of which are for material-systems not previously covered by the PED database.  The new content in this version reflects the explosion of research on the fundamental properties of materials needed to enable the transition to energy technologies that do not depend on fossil fuels.  New chemical systems and diagrams in v.5.1 are dominated by results from studies to develop low-cost, highly abundant, chemically stable materials for energy applications and include:  complex salt systems for advanced nuclear reactors (fuels, coolants), concentrated solar power (heat-transfer/storage), batteries, and fuel-cells; mixed oxide/non-oxide systems for electrodes (batteries, fuel-cells, photovoltaics); chalcogenide systems for electronic-ionic conductors (batteries, sensors); and semiconductor systems for solar-photovoltaics.  New diagrams added here also reflect increased research on the recycling/recovery of critical metals including rare earths, Sc, and key transition metals, as well as an uptick in studies of systems for ultra-lightweight structural materials for aerospace applications.

PHASE Version 5.1 uses the new PED Viewer for analyzing the diagrams. The browser-based programming in PHASE 5.1 is substantially easier to install, operate and maintain than previous versions.  This is on top of the user-friendly features already built into PHASE, For example, all Figures (the diagrams and commentary for a discrete ceramic materials system) are in .pdf file formats retrieved with a single click and formatted to be printable with book-quality resolution. 

PHASE 5.1 no longer requires JAVA. Thus online users can use any operating system such as Chrome, though a mouse (or other pointing device) and keyboard are still required. The USB version still requires PCs with Windows® operating systems.

Problems after installing PHASE 5.1 USB version

Some early users are reporting errors or "nothing" seems to be happening when starting the PHASE software after the initial installation. 

The most likely cause is software connections required for the operation are not being made successfully at installation. Specifically the application needs to be able to write to its folder C:\ProgramData\ACerS-NIST\ (or another folder if you altered the folder location during the setup away from the defaults). It is possible that there could be other restricted permissions later in the startup that would also cause problems.

Possible solutions:

  • Uninstall the PHASE software, then reinstall as an administrator
  • Ask IT group to check permissions on your system  
What are the technical requirements?
  • Web browser, Chrome or Firefox recommended
  • Document viewer for PDF files (Acrobat® or Foxit® or PDF enabled web browser)
  • Beginning with PHASE 5.0 (NIST SRD31) Java™ is no longer required. The analysis software uses a state-of-the-art browser-based graphics engine.  
  • PC running on Windows® 7 or 10 running in 64 bit mode (Phase USB does not install on 32 bit Windows, MACs, or other operating systems)
  • 2 GB RAM, 4 GB hard disk available, dual core processor 1.87 GHz or better
  • Ability to install programs as Administrator
What are the available formats for the PHASE product?

USB memory stick (PHASE USB) and web-based subscription (PHASE ONLINE).  Both have single-user and multi-user versions that use username/password verification. PHASE ONLINE has a Library version of that uses IP verification for access anywhere within an institutional or corporate network.

How do I choose the right format?

Answer four questions:

  • How many simultaneous workstations? More than one means multi-user or library version.
  • Will I use this on a MAC or other non-Windows PC workstation? Yes means PHASE ONLINE
  • Do I have a good internet connection? No means PHASE USB (yes means either will work)
  • Will my funding be ongoing or one-time only? One-time means PHASE USB (note that PHASE USB updates are not automatic and have additional costs per version)

For more information go to Compare and Purchase page

Are all published diagrams and commentaries included in the database?
The Phase Equilibria Diagrams database includes all ACerS/NIST commentaries and diagrams published by ACerS and/or NIST from the book Phase Diagrams for Ceramists Volume I through the current version of the PHASE database/software. 
Can I try before I buy?

Yes.  Go to the Free Phase Demo page to view demonstration videos and download the full software with limited trial database.

Which ceramic systems are included in the PED product?
  • Oxides and mixed systems with oxides
  • Chalcogenides (sulfides, selenides, tellurides)
  • Pnictides (N, P, As, Sb, Bi)
  • Carbides, Carbonates, Silicides, and Silicates
  • Actinides (U, Pu, Th)
  • Rare earths (Ce, Gd, Eu)
  • Oxy‐cation systems (molybdates, vanadates)
  • Semiconductors (Si, Ge, Sn)
  • Group 3 systems (B, Al, Ga, In, Tl)
  • Salts including mixed systems with salts
  • Others

Want to see if your ceramic or glass system is included? Download the Phase Demo.  The database contains the list of all ceramic systems found in the current version of PHASE.

How do I get more help?

If your questions were not answered, email us.

Why are phase equilibrium diagrams important?

Understanding phase equilibria in ceramic systems is central to the use and development of materials in refractories, glass, and other high-temperature technologies. Phase equilibria diagrams answer questions about flexibility and constraints of a ceramic or glass component in high-temperature or high-pressure environments. Phase boundaries also assist in the evaluation of the service stability of a ceramic material, both in the long and short time frames.  For an introdctory text on the use and interpretation of phase diagrams, please download General Discussions of Phase Diagrams by F.P. Hall, H. Insley, E.M. Levin, H.F. McMurdie and C.R. Robbins.


Am I permitted to republish the content contained in the ACerS-NIST Phase Equilibria Diagrams Search database?

Yes, but you must properly cite the source:

Phase Equilibria Diagrams Database (NIST Standard Reference Database 31), The American Ceramic Society and the National Institute of Standards and Technology, 2023. Figure Number(s) ____, ____; .