Accession Number : AD0671550

Title :   TERNARY PHASE EQUILIBRIA IN TRANSITION METAL-BORON-CARBON-SILICON SYSTEMS. PART 1. BINARY SYSTEMS. VOLUME 13. THE ZIRCONIUM-SILICON AND HAFNIUM-SILICON SYSTEMS

Descriptive Note : Documentary rept.

Corporate Author : AEROJET-GENERAL CORP SACRAMENTO CA MATERIALS RESEARCH LAB

Personal Author(s) : Brukl, C E

PDF Url : AD0671550

Report Date : May 1968

Pagination or Media Count : 73

Abstract : The zirconium-silicon and hafnium-silicon binary systems were investigated by means of Debye-Scherrer X-ray analysis, metallography, melting points, differential analysis techniques, and chemical analysis. Both silicide systems contain a D8(8)-type phase which is stabilized by trace impurities of oxygen and nitrogen. The binary phases present are: Zr4Si, Zr2Si, Zr3Si2, Zr5Si4, alpha- and Beta-ZrSi, and ZrSi2; in the hafnium system: Hf2Si, Hf3Si2, Hf5Si4, and HfSi2. The ZrSi phase undergoes an allotropic transformation at 1550C; the high temperature form is of the CrB type while the low temperature crystal structure is of the FeB type. Complete phase diagrams from 1100C up to melting are given.

Descriptors :   *HAFNIUM ALLOYS, *REFRACTORY MATERIALS, *SILICON ALLOYS, *ZIRCONIUM ALLOYS, CHEMICAL ANALYSIS, CRYSTAL STRUCTURE, DIFFERENTIAL THERMAL ANALYSIS, MELTING POINT, METALLOGRAPHY, PHASE DIAGRAMS, PHASE STUDIES, REFRACTORY METAL ALLOYS, TRANSFORMATIONS, X RAY DIFFRACTION

Subject Categories : Ceramics, Refractories and Glass
      Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE