Physical Chemistry

Metallurgical and Materials Transactions A

, Volume 27, Issue 7, pp 1919-1924

Gibbs energies of formation of chromium carbides

  • S. AnthonysamyAffiliated withIndira Gandhi Centre for Atomic Research
  • , K. AnanthasivanAffiliated withIndira Gandhi Centre for Atomic Research
  • , I. KaliappanAffiliated withIndira Gandhi Centre for Atomic Research
  • , V. ChandramouliAffiliated withIndira Gandhi Centre for Atomic Research
  • , P. R. Vasudeva RaoAffiliated withIndira Gandhi Centre for Atomic Research
  • , C. K. MathewsAffiliated withIndira Gandhi Centre for Atomic Research
  • , K. T. JacobAffiliated withDepartment of Metallurgy, Indian Institute of Science

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

The carbon potentials corresponding to the two-phase mixtures Cr + Cr23C6, Cr23C6 + Cr7C3, and Cr7C3 + Cr3C2 in the binary system Cr-C were measured in the temperature range 973 to 1173 K by using the methane-hydrogen gas equilibration technique. Special precautions were taken to prevent oxidation of the samples and to minimize thermal segregation in the gas phase. The standard Gibbs energies of formation of Cr23C6, Cr7C3, and Cr3C2 were derived from the measured carbon potentials. These values are compared with those reported in the literature. The Gibbs energies obtained in this study agree well with those obtained from solid-state cells incorporating CaF2 and ThO2(Y2O3) as solid electrolytes and sealed capsule isopiestic measurements reported in the literature.