RESEARCH ON CRITERIA FOR SELECTION OF ALLOYS AND SURFACE TREATMENTS FOR INHIBITION OF TUNGSTEN OXIDATION. PART III. STUDIES ON THE CHEMICAL AND PHYSICAL PROPERTIES OF TERNARY PHASES CONTAINING TUNGSTEN AND OXYGEN.
Abstract
Ternary Me-W-O systems are of interest because of the potential application of ternary phases as coatings for tungsten. Binary and ternary phase relations in three basic systems, Ti,Zr,Hf, tungsten and oxygen, were studied at temperatures up to 1700C. No compound formed along the TiO2-WO3 join in the Ti-W-O system. Binary mixtures begin melting at 1240C due to a eutectic at this temperature and 64 mole percent WO3. On the TiO2-WO2 join, a complete series of solid solution formed. For ternary compositions, metallic tungsten exists in equilibrium with all titanium oxides in various binary and ternary assemblages. In the Zr-W-O system, a cubic compound (ZrW2O8) forms above 1150C, and melts incongruently at 1257C to an assemblage consisting of ZrO2 and liquid. One eutectic and one pertectic were established in the binary system ZrO2-WO3, at 1231C and 74 mole percent WO3, and at 1257C and 71 mole percent WO3, respectively. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1966
- Accession Number
- AD0487348
Entities
People
- Bert Phillips
- Luke L. Y. Chang
- Margaret G. Scroger