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Thermal Expansion of Technical Solids at Low Temperatures; a Compilation

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Thermal Expansion of Technical Solids at Low Temperatures; a Compilation National Bureau of Standards Library, H.W. Bldg JUN 5 1961 NBS MONOGRAPH 29 Thermal Expansion of Technical Solids at Low Temperatures A Compilation From the Literature U.S. DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS THE NATIONAL BUREAU OF STANDARDS Functions and Activities The functions of the National Bureau of Standards are set forth in the Act of Congress, March 3, 1901, as amended by Congress in PubUc Law 619, 1950. These include the develop- ment and maintenance of the national standards of measm-ement and the provision of means and methods for making measurements consistent with these standards; the determination of physical constants and properties of materials; the development of methods and instruments for testing materials, devices, and structures; advisory services to government agencies on scientific and technical problems; invention and development of devices to serve special needs of the Govern- ment; arid the development of standard practices, codes, and specifications. The work includes basic and applied research, development, engineering, instrumentation, testing, evaluation, cali- bration services, and various consultation and information services. Research projects are also performed for other government agencies when the work relates to and supplements the basic program of the Bureau or when the Bureau's imique competence is required. The scope of activities is suggested by the listing of divisions and sections on the inside of the back cover. Publications The results of the Bm-eau's work take the form of either actual equipment and devices or published papers. These papers appear either in the Bureau's own series of pubHcations or in the journals of professional and scientific societies. The Bureau itself pubhshes three periodicals available from the Government Printing Office: The Journal of Research, published in four separate sections, presents complete scientific and technical papers; the Technical News Bulletin presents summary and prehminary reports on work in progress; and Basic Radio Propagation Predictions provides data for determining the best frequencies to use for radio communications throughout the world. There are also five series of nonperiodical publications: Monographs, Applied Mathematics Series, Handbooks, Miscellaneous Publications, and Technical Notes. Information on the Bureau's pubHcations can be found in NBS Circular 460, Publications of the National Bureau of Standards ($1.25) and its Supplement ($1.50), available from the Superintendent of Documents, Government Printing Office, Washington 25, D.C. UNITED STATES DEPARTMENT OF COMMERCE • Luther H. Hodges, Secretary NATIONAL BUREAU OF STANDARDS • A. V. Astin, Director Thermal Expansion of Technical Solids at Low Temperatures A Compilation From the Literature Robert J. Corruccini and John J. Gniewek National Bureau of Standards Monograph 29 Issued May 19, 1961 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington 25, D.C. - Price 20 cents I Thermal Expansion of Technical Solids at Low Temperatures * A Compilation From the Literature Robert J. Corruccini and John J. Gniewek Tables are given of the linear contraction relative to Table 3 gives data on some miscellaneous sub- 293 °K, (Lin — Lt) I L293, and the linear expansion coefficient, stances that did not fit into the format of table 2. dLIL^ndT, of thirty elements, forty-five alloys, twenty-two other inorganic substances and twenty plastics and elas- It was not practical to extend these data in any tomers in the temperature range, 0 to 300 °K. way, and so they are quoted almost verbatim from the original sources. Introduction Materials of construction often are anisotropic as a result of forming operations. This is espe- This publication was intended to fill a need cially noticeable with among designers of cryogenic equipment for a metals having highly aniso- tropic crystal compilation of thermal expansion data on cryo- lattices, such as zinc, and with plastics based chain polymers. genic materials. The literature search relied on The degree of preferred orientation in such materials be un- primarily on Physics Abstracts and is believed to may controlled and, consequently, measurements of provide complete coverage of the published liter- the linear thermal expansion greatly ature through 1958. It was found that very few may vary with sample history orientation. additional references were derived from subse- and Measure- that are in only direction quently searchijig other sources. ments made one of such a material can be given little weight. Wherever possible, data have been presented Wherever a complete set of linear expansions along mutually throughout the range, 0 to 300 °K. However, perpendicular directions were available, we cal- the region below 100° K is of predominant culated the linear expansion for presentation importance in cryogenic engineering, and, hence, mean in table 2. This quantity is to a very good many substances of interest have been omitted approximation one-third the volume expansion and because data were not available below 100 °K. is the linear expansion that would be observed in Certain substances which are usually used as the absence of preferred orientation. Although fluids in cryogenics have been omitted. These such a condition may not often be perfectly realiz- are helium, hydrogen, deuterium, neon, nitrogen, able, it represents average behavior and is a carbon monoxide, fluorine, argon, oxygen, air, and precisely defined physical quantity. In order to methane. Various properties of aU phases of show the maximum possible variation in the linear these substances are being compiled separately at expansion with orientation we have given in table this laboratory. 4 representative values along the principal crys- The published data usually consisted of mi- tallographic axes for some of the more anisotropic smoothed values of length change. It was elements. These data were taken directly from necessary to adjust these to our adopted reference the literature without smoothing. temperature of 293 °K, to smooth and interpolate cycling of polycrystalline materials in at rounded values of temperatm-e, and to differ- Thermal which the crystallites are anisotropic produces in- entiate. Most of the results are given in table 2. cases plastic defor- The references on which the resulting data were ternal stresses. In extreme can result. This has been observed in tin, based are indicated in each table as "Sources of mation zinc Boas and Honeycombe above data". All other sources of low temper- cadmium, and by in graphite by Hidnert [1934] and ature data for each substance are listed as "Other [1947] and and Meyer [1955]. references". The selection of best sources will Baskin classes of experiniental not be justified in detail. In general it was based There are two main lattice pa- on the precision of the data, the original authors' methods using macroscopic and X-ray In a few cases estimates of accuracy, and the quality of the rameter techniques, respectively. appreciable samples. The bibliography gives complete refer- [Glover, 1954; Gott, 1942; Smith, 1954] the two ences to the sources associated with the tables of differences in thermal expansion by found, amounting to over 10 data. In addition, it contains selected references methods have been others have found on theory, experimental techniques, and measure- percent at the worst. However, experimental error except ments of other substances which were outside our no difference exceeding Saini, Weigle, and scope but which were thought to be of more than near the melting point [Austin, Connell and Martin, average interest. The bibliography attempts to Pierce, 1940; Berry, 1953; Galen, 1957; Feder and be complete only with regard to the substances 1951; van Duijn and van Hume-Rothery and Andrews, 1942; listed in table 1. Nowick, 1958; Hume-Rothery and Boultbee, 1949; Hume-Roth- •This work was partly supported by Wright Air Development Center, and Baluffi, Air Research and Development Command U.S. Air Force. ery and Strawbridge, 1947; Simmons 1 — . 1959, 1960; Wagner and Beyer, 1936]. Such the specific heat due to electrons is appreciable. differences, if real, would require high concentra- Mikura [1941] and Visvanathan [1951] have shown tions of vacancies or nonuniform distribution of that a corresponding linear term in dLjLdT should lattice defects. The dimensional effects produced appear, but the coefficient of this term has been by lattice defects have been analyzed by Eshelby calculated only for the free-electron case. [1953, 1954, 1956], Miller and Russell [1952, 1953], Anomalies in the thermal expansion may occur and Toupin and Rivlin [I960]. The effect of im- for various reasons. In fact, dilatometry is a purities in metals is illustrated by measurements useful tool for exploring solid-state transforma- due to Hume-Rothery and Boultbee [1949]. The tions. Some examples of substances showing low efl'ect of elastic strain has been examined by temperature anomalies are Dy (ferromagnetic Rosenfield and Averbach [1956] and the effect of Curie point), KH2PO4 (ferroelectric Curie point), plastic deformation has been examined by Hordon, MnO (anti-ferromagnetic transformation or Neel Lement, and Averbach [1958]. point), N2 (fii'st order phase change), CH4 (rota- Smoothing and interpolation were necessary tional transition) and soft rubbers ("glass" with many substances in order to obtain tables transition) that were sufficiently detailed to be useful. It Articles by Bijl [1957],
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