Thermal analysis of amalgams

S. Tsutsumi, M. Nakamura, Jack Ferracane, T. L. Schiller, T. Hanawa, T. Okabe

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

This study provides further information about the thermal behavior of dental amalgams. A differential thermal analyzer with a thermogravimetric analyzer, and a differential scanning calorimeter (DSC) were employed to examine the thermal stability and phase changes of low and high-copper amalgams. The analysis was performed in air over a temperature range of 25-130°C. Within experimental error (TG sensitivity=20 μg), there was no weight change in any of the amalgams tested. It is suggested that a film formed on the amalgam surface that kept mercury release to a minimum. As previously reported, DSC thermograms have indicated the existence of a phase transformation in both low and high-copper amalgams. Near 80°C, the γ1 in low-copper amalgam transformed to a liquid phase as a result of a solid-state reaction between the existing phases. In high-copper amalgam, the phase transformation occurred at a higher temperature, approximately 100°C, due to the reaction between γ1 and γ and the lack of γ2 in the amalgam. In both cases, the γ1 phase transformed to β1 at the endothermic peak. The heat of reaction estimated from integration of the endothermic peak in each DSC thermogram was approximately the activation energy for diffusion of mercury in amalgam phases and the heat of fusion of γ1 and γ2 in the amalgams.

Original languageEnglish (US)
Pages (from-to)307-311
Number of pages5
JournalDental Materials
Volume4
Issue number5
DOIs
StatePublished - 1988
Externally publishedYes

Fingerprint

Mercury amalgams
Thermoanalysis
Hot Temperature
Copper
Mercury
Calorimeters
Dental Amalgam
Mercury (metal)
Temperature
Scanning
Dental amalgams
Phase transitions
Air
Weights and Measures
Solid state reactions
Thermodynamic stability
Fusion reactions
Activation energy

Keywords

  • amalgam, thermal stability, phase change

ASJC Scopus subject areas

  • Mechanics of Materials
  • Materials Science(all)
  • Dentistry(all)

Cite this

Tsutsumi, S., Nakamura, M., Ferracane, J., Schiller, T. L., Hanawa, T., & Okabe, T. (1988). Thermal analysis of amalgams. Dental Materials, 4(5), 307-311. https://doi.org/10.1016/S0109-5641(88)80027-7

Thermal analysis of amalgams. / Tsutsumi, S.; Nakamura, M.; Ferracane, Jack; Schiller, T. L.; Hanawa, T.; Okabe, T.

In: Dental Materials, Vol. 4, No. 5, 1988, p. 307-311.

Research output: Contribution to journalArticle

Tsutsumi, S, Nakamura, M, Ferracane, J, Schiller, TL, Hanawa, T & Okabe, T 1988, 'Thermal analysis of amalgams', Dental Materials, vol. 4, no. 5, pp. 307-311. https://doi.org/10.1016/S0109-5641(88)80027-7
Tsutsumi S, Nakamura M, Ferracane J, Schiller TL, Hanawa T, Okabe T. Thermal analysis of amalgams. Dental Materials. 1988;4(5):307-311. https://doi.org/10.1016/S0109-5641(88)80027-7
Tsutsumi, S. ; Nakamura, M. ; Ferracane, Jack ; Schiller, T. L. ; Hanawa, T. ; Okabe, T. / Thermal analysis of amalgams. In: Dental Materials. 1988 ; Vol. 4, No. 5. pp. 307-311.
@article{2130436a0424426f9f5a8eb2b61ad70e,
title = "Thermal analysis of amalgams",
abstract = "This study provides further information about the thermal behavior of dental amalgams. A differential thermal analyzer with a thermogravimetric analyzer, and a differential scanning calorimeter (DSC) were employed to examine the thermal stability and phase changes of low and high-copper amalgams. The analysis was performed in air over a temperature range of 25-130°C. Within experimental error (TG sensitivity=20 μg), there was no weight change in any of the amalgams tested. It is suggested that a film formed on the amalgam surface that kept mercury release to a minimum. As previously reported, DSC thermograms have indicated the existence of a phase transformation in both low and high-copper amalgams. Near 80°C, the γ1 in low-copper amalgam transformed to a liquid phase as a result of a solid-state reaction between the existing phases. In high-copper amalgam, the phase transformation occurred at a higher temperature, approximately 100°C, due to the reaction between γ1 and γ and the lack of γ2 in the amalgam. In both cases, the γ1 phase transformed to β1 at the endothermic peak. The heat of reaction estimated from integration of the endothermic peak in each DSC thermogram was approximately the activation energy for diffusion of mercury in amalgam phases and the heat of fusion of γ1 and γ2 in the amalgams.",
keywords = "amalgam, thermal stability, phase change",
author = "S. Tsutsumi and M. Nakamura and Jack Ferracane and Schiller, {T. L.} and T. Hanawa and T. Okabe",
year = "1988",
doi = "10.1016/S0109-5641(88)80027-7",
language = "English (US)",
volume = "4",
pages = "307--311",
journal = "Dental Materials",
issn = "0109-5641",
publisher = "Elsevier Science",
number = "5",

}

TY - JOUR

T1 - Thermal analysis of amalgams

AU - Tsutsumi, S.

AU - Nakamura, M.

AU - Ferracane, Jack

AU - Schiller, T. L.

AU - Hanawa, T.

AU - Okabe, T.

PY - 1988

Y1 - 1988

N2 - This study provides further information about the thermal behavior of dental amalgams. A differential thermal analyzer with a thermogravimetric analyzer, and a differential scanning calorimeter (DSC) were employed to examine the thermal stability and phase changes of low and high-copper amalgams. The analysis was performed in air over a temperature range of 25-130°C. Within experimental error (TG sensitivity=20 μg), there was no weight change in any of the amalgams tested. It is suggested that a film formed on the amalgam surface that kept mercury release to a minimum. As previously reported, DSC thermograms have indicated the existence of a phase transformation in both low and high-copper amalgams. Near 80°C, the γ1 in low-copper amalgam transformed to a liquid phase as a result of a solid-state reaction between the existing phases. In high-copper amalgam, the phase transformation occurred at a higher temperature, approximately 100°C, due to the reaction between γ1 and γ and the lack of γ2 in the amalgam. In both cases, the γ1 phase transformed to β1 at the endothermic peak. The heat of reaction estimated from integration of the endothermic peak in each DSC thermogram was approximately the activation energy for diffusion of mercury in amalgam phases and the heat of fusion of γ1 and γ2 in the amalgams.

AB - This study provides further information about the thermal behavior of dental amalgams. A differential thermal analyzer with a thermogravimetric analyzer, and a differential scanning calorimeter (DSC) were employed to examine the thermal stability and phase changes of low and high-copper amalgams. The analysis was performed in air over a temperature range of 25-130°C. Within experimental error (TG sensitivity=20 μg), there was no weight change in any of the amalgams tested. It is suggested that a film formed on the amalgam surface that kept mercury release to a minimum. As previously reported, DSC thermograms have indicated the existence of a phase transformation in both low and high-copper amalgams. Near 80°C, the γ1 in low-copper amalgam transformed to a liquid phase as a result of a solid-state reaction between the existing phases. In high-copper amalgam, the phase transformation occurred at a higher temperature, approximately 100°C, due to the reaction between γ1 and γ and the lack of γ2 in the amalgam. In both cases, the γ1 phase transformed to β1 at the endothermic peak. The heat of reaction estimated from integration of the endothermic peak in each DSC thermogram was approximately the activation energy for diffusion of mercury in amalgam phases and the heat of fusion of γ1 and γ2 in the amalgams.

KW - amalgam, thermal stability, phase change

UR - http://www.scopus.com/inward/record.url?scp=0024102618&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0024102618&partnerID=8YFLogxK

U2 - 10.1016/S0109-5641(88)80027-7

DO - 10.1016/S0109-5641(88)80027-7

M3 - Article

C2 - 3248696

AN - SCOPUS:0024102618

VL - 4

SP - 307

EP - 311

JO - Dental Materials

JF - Dental Materials

SN - 0109-5641

IS - 5

ER -