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Guide to Rheological Nomenclature: Measurements in Ceramic Particulate Systems NfST Nisr National institute of Standards and Technology Technology Administration, U.S. Department of Commerce NIST Special Publication 946 Guide to Rheological Nomenclature: Measurements in Ceramic Particulate Systems Vincent A. Hackley and Chiara F. Ferraris rhe National Institute of Standards and Technology was established in 1988 by Congress to "assist industry in the development of technology . needed to improve product quality, to modernize manufacturing processes, to ensure product reliability . and to facilitate rapid commercialization ... of products based on new scientific discoveries." NIST, originally founded as the National Bureau of Standards in 1901, works to strengthen U.S. industry's competitiveness; advance science and engineering; and improve public health, safety, and the environment. One of the agency's basic functions is to develop, maintain, and retain custody of the national standards of measurement, and provide the means and methods for comparing standards used in science, engineering, manufacturing, commerce, industry, and education with the standards adopted or recognized by the Federal Government. As an agency of the U.S. Commerce Department's Technology Administration, NIST conducts basic and applied research in the physical sciences and engineering, and develops measurement techniques, test methods, standards, and related services. The Institute does generic and precompetitive work on new and advanced technologies. NIST's research facilities are located at Gaithersburg, MD 20899, and at Boulder, CO 80303. Major technical operating units and their principal activities are listed below. For more information contact the Publications and Program Inquiries Desk, 301-975-3058. 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NIST Special Publication 946 Guide to Rheological Nomenclature: Measurements in Ceramic Particulate Systems Vincent A. Hackley Ceramics Division Materials Science and Engineering Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899-8520 Chiara F. Ferraris Building Materials Division Building and Fire Research Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899-8621 January 2001 U.S. DEPARTMENT OF COMMERCE Norman Y. Mineta, Secretary TECHNOLOGY ADMINISTRATION Dr. Cheryl L. Shavers, Under Secretary of Commerce for Technology NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY Karen H. Brown, Acting Director National Institute of Standards and Technology Special Publication 945 Natl. Inst. Stand. Technol. Spec. Publ. 946, 31 pages (January 2001) CODEN: NSPUE2 U.S. GOVERNMENT PRINTING OFFICE WASHINGTON: 2001 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, DC 20402-9325 Guide to Rheological Nomenclature Preface Nomenclature is fundamentally important to the progress of science and technology. Because of the rapidly growing volume of available technical information, and the speed with which this information must now be processed, it is critical to have a uniform terminology in place for describing experimental methods and instrumentation, to facilitate the exchange of material property data and for sharing technical ideas and concepts. This is especially true for the ceramics industry because of its breadth and interdisciplinary nature. The present document addresses the issue of nomenclature for one important area of ceramic science: rheology and rheometric measurements. Ceramic suspensions, gels and pastes are the starting materials for a wide variety of applications, playing critical roles in the processing of products ranging from whitewares to concrete to paint and pigments to high-tech multilayer ceramic packages for the advanced electronics industry. Unfortunately, researchers and engineers working in these diverse fields often speak different languages, thus resulting in miscommunication and ambiguity. Even within the same field, variations in terminology are common. The need for widely accepted, uniform and precise nomenclature was emphasized recently by the Ceramic Processing Characterization Council^ (CPCC), a voluntary organization of participants representing industry, instrument companies, academia and government. CPCC members identified nomenclature as a high priority issue in the areas of dispersion and rheology. In response to this need, we have initiated a series of guides to help in the interpretation of nomenclature and data relating to particle-liquid ceramic systems. In compiling the present guide, we drew upon a number of sources, including books, review articles and published terminologies. To the extent possible, an effort was made to maintain a degree of uniformity with existing standards and conventions. To this end, definitions are generally consistent with nomenclatures published by the American Concrete Institute (ACI), the British Standards Institute (BSI), the International Union of Pure and Applied Chemistry (lUPAC) and the Society of Rheology. A complete bibliography of sources is provided. An international ad hoc committee was formed to review the technical content and language of the nomenclature and to offer input where needed. The committee members represent a broad spectrum of experts from industry, academia and government, and include (in alphabetical order) Lennart Bergstrom (YKI), John Dealy (McGill University), Ed Garboczi (NIST), Bob Hunter (University of Sydney), Kamal Khayat (University of Sherbrooke), FranQois de Larrard (Laboratoire Central des Ponts et Chaussees), Makio Naito (JFCC), Celik Ozyildirim (Virginia Transportation Research Council), Ponserril Somasundaran (Columbia University), and Abbas Zaman (University of Florida). Their efforts are gratefully acknowledged. It is our primary hope that this document will serve as a resource to those working in particle systems applications, particularly in the ceramic sciences. It is our further hope that this document will serve to promote the establishment of a commonly recognized system of terminology throughout the ceramics community. Formerly the Ceramic Processing Characterization Consortium iii 31 Guide to Rheological Nomenclature Table of Contents PREFACE iii 1. INTRODUCTION 1 2. FUNDAMENTAL RHEOLOGICAL PROPERTIES 1 3. FUNCTIONAL FORMS OF VISCOSITY 2 4. GLOSSARY OF BASIC TERMINOLOGY 4 5. CLASSIFICATION OF EQUILIBRIUM FLOW CURVES 7 6. EXPRESSIONS FOR DESCRIBING STEADY SHEAR NON-NEWTONIAN FLOW 8 7. TIME-DEPENDENT EFFECTS 11 8. OSCILLATORY MEASUREMENTS 13 Material Functions Derived from Oscillatory Tests 1 9. MEASUREMENT APPARATUS 15 Capillary Methods 16 Rotational Methods 17 10. CONCRETE AND OTHER COARSE-GRAINED MATERIALS 19 Glossary of Rheological Terms 20 Glossary of Test Methods 2 1 1 . UNITS AND SYMBOLS 23 Rheometric Units 23 List of Symbols 24 BIBLIOGRAPHY 25 Primary Sources 25 Other Sources 26 ACKNOWLEDGMENTS 27 AD HOC REVIEW COMMITTEE 27 INDEX 29 iv Guide to Rheological Nomenclature GUIDE TO RHEOLOGICAL NOMENCLATURE FOR LIQUID-BASED PARTICLE SYSTEMS 1. Introduction Measurements and standards play an integral role in the manufacture and utilization of ceramic powders, components, coatings and composites. They enhance reliability by providing a basis for quantifying and comparing material properties during each phase of the manufacturing process, from raw materials to the finished product. Equally important is the establishment of a uniform and widely accepted nomenclature to permit the efficient exchange of scientific and technical information, and to provide a sound basis on which to standardize measurement methods and data reporting practices. This document represents the second^ in a series of guides intended to serve the dual purpose
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