Phase Diagram FAQ
What is the ACerS-NIST Phase Equilibria Diagrams Program?
Program Origins: For nearly seventy years the National Institute of Standards and Technology (NIST) and The American Ceramic Society (ACerS) have collaborated on the publication of evaluated phase diagrams for ceramic systems. The joint Ceramic Phase Diagram program, representing a continuation and expansion of the effort to make ceramic phase diagram information readily and comprehensively available, was initiated in December 1982. The program goal is to support growth and progress in the ceramics industries by providing relevant, critically evaluated phase diagrams. To achieve this, a multiyear program was established to improve currency with the archival literature and to provide critically evaluated phase diagrams for oxides, non-oxides, salts, carbides, nitrides, borides, compound semiconductors, pnictides and chalcogenides.
Program Responsibility: To achieve the goals of the expanded program, a multiyear effort was established with support from NIST and other federal agency programs and from a fund-raising effort managed by ACerS. NIST provides overall coordination and technical guidance and ensures quality data coverage and evaluation. NIST also developed the original digitization software used to generate the graphics portion of the database. ACerS is responsible for the production aspects, dissemination of the data in printed form, maintenance of the electronic database, and development of the software to create the CD-ROM and other electronic formats.
Why are Phase Equilibria Diagrams important?
According to “Introduction to Phase Equilibria in Ceramics,” an understanding of phase equilibria in ceramic systems is central to the utilization and development of materials in refractories, glass, and other high-temperature technologies. Phase equilibria address significant questions related to the flexibility and constraints, dictated by forces of nature, on the evolution of phase assemblages in ceramics. Phase boundaries also assist in the evaluation of the service stability of a ceramic material, both in the long and short time frames. Thus, knowledge of the stability of a ceramic or glass component in high-temperature or high-pressure environments can often be obtained from an appropriate stable or metastable phase diagram.
“In the processing and manufacture of ceramic products, the reactions which occur are understood more clearly if the phase relations under equilibrium conditions are known. The chemical and physical properties of ceramic products are related to the number, composition, and distribution of the phases present. Temperature, pressure, and composition are the principal variables which determine the kinds and amounts of the phases present under equilibrium conditions. To ceramists, who much understand the effects of these variables on both the processing and the properties of the finished product, the phase equilibrium relations (usually presented in the form of phase diagrams) provide the necessary fundamental information.”
For a step-by-step introductory text on the use and interpretation of phase diagrams, please purchase “Introduction to Phase Equilibria in Ceramics” By Clifton G. Bergeron and Subash H. Risbud.
Download “General Discussions of Phase Diagrams” for free information on phase diagrams. “General Discussion of Phase Diagrams” was written by F.P. Hall, H. Insley, E.M. Levin, H.F. McMurdie and C.R. Robbins and is from “Phase Diagrams for Ceramists, Volume I;” edited by E.M. Levin, C.R. Robbins and H.F. McMurdie, pages 5-36, 1964.
What is the ACerS-NIST Phase Equilibria Diagrams Database?
The ACerS-NIST Phase Equilibria Diagrams Database is the primary product of the long-standing cooperative effort between the National Institute of Standards and Technology (NIST) and The American Ceramic Society (ACerS) to provide high-quality phase diagram data to the technical community. When the cooperative program was formalized in 1982, the computerization of all data activities was established as a major goal. As part of this effort, the Ceramic Phase Diagrams Data Center developed computer files for all references, commentaries, and chemical classification information, as well as the diagrams themselves, in graphics form. These computer files form the basis for the ACerS-NIST Phase Equilibria Diagrams Database.
What Ceramic Systems are included in the ACerS-NIST Phase Equilibria Diagrams Database?
The ACerS-NIST Phase Equilibria Diagrams CD-ROM Database Version 3.4 contains 892 new entries with approximately 1,400 new diagrams, bringing the total number of diagrams to approximately 24,800. This searchable CD includes all the information printed in the 21 hard-copy volumes as well as “virtual” Volume 15. The 889 new figures in this release include 616 in (virtual) Volume 16 and 271 in special Volume P (phosphorus-containing), and comprise the largest-ever update of Phase Equilibria Diagrams (NIST Standard Reference Database 31).The new content includes:
- Phosphates – batteries, laser and other optoelectronic materials
- Chalcogenides – semiconducting sulfides, selenides and tellurides for thermoelectrics, optoelectronics, photovoltaics
- Pnictide systems – nitrides, phosphides,
arsenides, bismuthides, and antimonides for bandgap-engineered optical
materials, electron-transport devices, sensors, detectors,
- Actinides – (U, Pu, Th) and actinide-surrogates (Ce)
- Oxide and mixed systems with oxides – electrode
processing, catalysis, electroceramics, magneto-resistors, thermistors,
capacitors, nuclear fuel and nuclear waste, ionic conductors, fuel-cell
- Oxycation systems – molybdates and vanadates
- Semiconductors – Si, Ge, Sn
- Group 3 systems – B, Al, Ga, In, Tl
- Salts – including mixed systems with salts
How Do I Access the ACerS-NIST Phase Equilibria Diagrams Database?
There are two primary ways to access ACerS-NIST Phase Diagrams:
What is the Phase Equilibria Diagrams CD-ROM Database, Version 3.4?
Phase Equilibria Diagram CD-ROM Database 3.4 includes 892 new figures and approximately 1400 new phase diagrams and provides experimental and calculated data for an unprecedented range of non-organic material-types pertinent to a wide variety of applications. Version 3.4 is available in single and multiple user licenses. Version 3.4 includes over 2,500 electronic-only diagrams published since 2008 as well as the information previously printed in the 21-volume book series.
Which license option is right for me?
There are two licenses available for the ACerS-NIST Phase Equilibria Diagrams CD-ROM Database, Version 3.4:
- Single User License – Select this license if you only need to have ACerS-NIST Phase Equilibria Diagrams CD-ROM Database on one computer.
- Multiple User License – Select this license if more than one person in your organization needs to have access to ACerS-NIST Phase Equilibria Diagrams CD-ROM Database, or if you would like to put it on a computer network.
What are the System Requirements for ACerS-NIST Phase Equilibria Diagrams CD-ROM Database, Version 3.4?
- Microsoft Windows 98, ME, NT 4.0, Windows 2000, XP or Server 2003
- Although the database is developed to run on Microsoft Windows XP, users have been able to run the database successfully on Microsoft Vista and Windows 7
- 450 MB available hard-disk space
- Internet Explorer 5, 6, or 7 to enable full utilization of the Help files (installation of the latest service packs is recommended)
- CD-ROM drive (if installation is done from a CD-ROM)
- Super VGA (800 x 600) or higher-resolution monitor with 256 colors (true-color 32 bit is required for full utilization of lever-rule and curve-follow functions)
- Adobe Acrobat Reader (available for free at www.adobe.com) is required for viewing .pdf files
What is the ACerS-NIST Phase Equilibria Diagrams Online?
Phase Online features 23,000 evaluated phase diagrams of ceramic systems specifically addressing oxides, salts, carbides, nitrides, boride, compound semiconductors and chalcogenides. New diagrams (labeled as volume 15) include oxide as well as non-oxide systems such as chalcogenides and pnictides, phosphates, salt systems, and mixed systems of these various ceramic materials classes. Anyone may search the entire database using the search function on the homepage, and view a thumbnail sketch of each diagram; however, a subscription is required to fully view diagrams and commentaries. For more information, visit http://phase.ceramics.org
Which Subscription option is right for me?
ACerS-NIST Phase Equilibria Diagrams Online offers three types of licenses:
- Single User – Single user subscription options include (a) 1 diagram, (b) one month, unlimited diagrams, and (c) one year, unlimited diagrams.
- Multiple User – Select this option if you have up to 10 people in your organization who need one-year password protected access to Phase Online.
- Library - Select this option if you are an institution that wants to provide IP based access to your clients.
What if I only need certain ceramic phase diagrams?
Access approximately 24,800 evaluated Phase Diagrams online, anytime, anywhere in a convenient, flexible and affordable manner. Visit http://phase.ceramics.org to search the extensive database and purchase only the diagrams you need.
How do I order a phase diagram product for ceramic systems?
Visit the Phase Diagram section and select which of the four products (CD, Online, Technical Books or Topical CDs) works for you. Follow the links to place an order or contact customer service at firstname.lastname@example.org or inside the U.S. at 866-721-3322; outside the U.S. at 240-646-7054 for more information.
What if I have a question that isn’t answered here?
Contact Mark Mecklenborg at email@example.com