International Journal of Thermophysics

, Volume 29, Issue 1, pp 126–138 | Cite as

A New Method for the Quantification and Correction of Thermal Effects on the Realization of Fixed Points



The temperature and flatness (shape) of a fixed-point plateau depend on both the amount and nature of specific impurities and on thermal effects that are influenced by the fixed-point cell design and furnace properties. A better understanding and experimental proof of the influence of specific impurities on fixed-point realizations require the separation of impurity influences from thermal effects. In this paper the influence of heat exchange between the thermometer and furnace is quantified via a method based on changing the furnace temperature during the fixed-point measurement. It will be shown that the corresponding correction of this thermal effect has a dominant influence on the plateau shape compared to the influence of impurities. This leads to an explanation for why the maximum of an induced freeze is the most reproducible temperature. A secondary outcome is an explanation of why natural freezes have less flat plateaux compared to induced freezes, resulting in fixed-point temperatures that are too low. Furthermore, the suggested procedure is the basis of the direct and quantitative comparison of fixed-point cells and the detection of weak points within a specific design. It allows optimization of fixed-point cells and furnaces, and helps to deepen the common understanding of the phase transition in fixed-point cells.


Heat conduction Induced freeze ITS-90 Temperature fixed points Thermal correction Uncertainty budget Natural freeze 


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  1. 1.
    Bureau International des Poids et Mesures, Supplementary Information for the ITS-90, (BIPM, Sèvres, 1990)Google Scholar
  2. 2.
    CCT-WG1: D. Ripple, B. Fellmuth, M. de Groot, Y. Hermier, K.D. Hill, P.P.M. Steur, A. Pokhodun, M. Matveyev, P. Bloembergen, Methodologies for the estimation of uncertainties and the correction of fixed-point temperatures attributable to the influence of chemical impurities. Working document of the Comité Consultatif de Thermométrie, CCT/0508 Google Scholar
  3. 3.
    Burton J.A., Prim R.C., Slichter W.P. (1953) J. Chem. Phys. 21:1987CrossRefADSGoogle Scholar
  4. 4.
    Smith V.G., Tiller W.A., Rutter J.W. (1955) Can. J. Phys. 33:723Google Scholar
  5. 5.
    Tiller W.A., Sekerka R.F. (1964) J. Appl. Phys. 35:2726CrossRefADSGoogle Scholar
  6. 6.
    Verhoeven J.D., Heimes K.A. (1971) J. Cryst. Growth 10:179CrossRefGoogle Scholar
  7. 7.
    Tiller W.A., Jackson K.A., Rutter J.W., Chalmers B. (1953) Acta Metall. 1:428CrossRefGoogle Scholar
  8. 8.
    CCT-WG1: B.W. Mangum, P. Bloembergen, M.V. Chattle, P. Marcarino, A.P. Pokhodun, Recommended techniques for improved realization and intercomparisons of defining fixed points. Working Document of the Comité Consultatif de Thermométrie, CCT/96–08, pp. 5–7Google Scholar
  9. 9.
    Pfann W.G. (1966) Zone Melting. Wiley, New YorkGoogle Scholar
  10. 10.
    Fellmuth B., Hill K.D. (2006) Metrologia 43:71CrossRefADSGoogle Scholar
  11. 11.
    Widiatmo J.V., Harada K., Yamazawa K., Arai M. (2006) Metrologia 43:561CrossRefADSGoogle Scholar
  12. 12.
    Ma C.K., Bedford R.E. (1996) Metrologia 33:319CrossRefADSGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.Physikalisch-Technische BundesanstaltBerlinGermany

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