Monatshefte für Chemie / Chemical Monthly

, Volume 105, Issue 1, pp 156–168 | Cite as

Eine σ-Phase im System Chrom—Molybdän—Silicium

  • E. Rudy
  • H. Nowotny
Anorganische, Struktur- und Physikalische Chemie

A σ-phase in the system chromium—molybdenum—silicon

Abstract

A ternary σ-phase (Cr0.39–0.57Mo0.47–0.29Si0.14) has been detected in the chromium—molybdenum—silicon system at 1500 °C. The novel σ-phase, which displays only a small degree of ordering, undergoes eutectoid decomposition at ca. 1200 °C, into (Cr, Mo)+(Cr,Mo)3Si. The relative stability bility of the ternary σ-phase and the non-existing binary σ-phases (Cr−Si, Mo−Si) were estimated from the observed equilibria. With respect to the coexistent phases there is an amount of 2500 cal/g atom metal necessary for stabilizing of the ternary σ-phases at 1500 °C. The slight deviation from completely random distribution reflects on the entropy change and there is fair agreement with the entropy change calculated from the temperature dependency of ΔGz, σ.

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Copyright information

© Springer-Verlag 1974

Authors and Affiliations

  • E. Rudy
    • 1
    • 2
  • H. Nowotny
    • 1
    • 2
  1. 1.Department of Materials ScienceOregon Graduate CenterBeavertonUSA
  2. 2.Institut für Physikalische Chemie der UniversitätWienÖsterreich

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