TERNARY PHASE EQUILIBRIA IN TRANSITION METAL-BORON-CARBON-SILICON SYSTEMS. PART II. TERNARY SYSTEMS. VOL. 14. THE HAFNIUM-IRIDIUM-BORON SYSTEM
Abstract
Constitution diagrams of the binary hafnium-iridium and iridium-boron systems as well as an isothermal section of the hafnium-iridium-boron ternary system have been established by means of Pirani melting point investigations, metallography, Debye-Scherrer X-ray, and chemical analysis. There are three intermediate phases, Ir(3)B(2), IrB(0.89), and IrB(1.50) in the rather low melting iridium-boron system which contains four eutectics. Hf2Ir, Hf3Ir2, HfIr(1-x), HfIr, HfIr(1+x), and HfIr3 are the phases present in the hafnium- iridium system. The highest melting phase in this system is HfIr(3) whose melting point is 2460 C. The phase relationships in the central portion of the binary system are quite complex. The ternary hafnium-iridium-boron system has five ternary phases: Hf(.32)Ir(.46)B(.22), Hf(.19)Ir(.49)B(.32), Hf(.07)Ir(.51) B(.42), Hf(.07)Ir(.42)B(.51), and Hf(.02)Ir(.60)B(.38). HfIr3 has an extended solubility for boron. HfB2, which does not form a two-phase equilibrium with iridium, exhibits no solubility into the ternary field. High temperature application possibilities of hafnium-iridium-boron composite borides are briefly discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1967
- Accession Number
- AD0820649
Entities
People
- Charles E. Brukl
- Erwin Rudy
Organizations
- Aerojet Rocketdyne Holdings