Original scientific paper

Selective Oxidation of Zirconium in Zr₂Cu

Matija Paljević ; Ruđer Bošković Institute, PO.B. 1016, 10001 Zagreb, Croatia
Marijan Tudja ; Pliva d.d., Prilaz baruna Filipovića 25, 10000 Zagreb, Croatia

Abstract

The high-temperature oxidation of Zr₂Cu in dry oxygen is characterized by selective oxidation of zirconium. The excess of copper is accumulated in the matrix alloy at the alloy-oxide interface forming the Zr₈Cu₅ phase. The oxide layer consists of monoclinic ZrO₂ and a small amount of CuO. Additionally, tetragonal ZrO₂ appears up to 873 K at the surface, and Cu₂O is formed above 873 K, deeper in the oxide layer. The reaction kinetics obeys a parabolic rate law. An activation energy of 54.4 kJ/mol has been estimated in the temperature range 773-1123 K. An anomalous decrease of the oxidation rate occurs at 1155-1223 K, after a strong reaction at 1073-1150 K.

Keywords

corrosion; oxidation; alloys; Zr₂Cu; high temperature; selective

Hrčak ID:

132181

URI

https://hrcak.srce.hr/132181

Publication date:

1.9.1999.

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