THE VAPORIZATION AND PHYSICAL PROPERTIES OF CERTAIN REFRACTORIES. PART I. TECHNIQUES AND PRELIMINARY STUDIES

Technical Report · Mon Aug 01 04:00:00 EDT 1960

OSTI ID:4111323

Hasapis, A A; Panish, M B; Rosen, C

Simple effusion studies of the vaporization of rhodium, iridium, and osmium were undertaken by the Knudsen effusion technique. The rate of effusion was determined by condensing the molecular beam on a target. Rhodium was studied from 2051 to 2205 deg K. In this temperature range, its heat of vaporization was found to be 129 kcal/mole. Iridium was studied from 2600 to 2600 deg K. In this range, its tentative heat of vaporization is 155 plus or minus 5 kcal/mole. It was noted that some interaction between the iridium, the thoria liner, and the tungsten outer liner of the effusion cell may have occurred. No data were obtained for the vaporization of osmium because of extensive interaction between the thoria liner and the tungsten outer liner of the effusion cell. Mass spectrometric studies have been made of the vaporization of thoria from tungsten effusion cells. Interactions between thoria and tungsten at elevated temperatures were noted. Tentative data on the vaporization of thoria to ThO and ThO/sub 2/ were obtained and are presented. Mass spectrometric studies of the vaporizatlon of Al/sub 2/O/sub 3/ in contact with tungsten have been made in conjunction with compatibility studies of tungsten and Al/sub 2/O/sub 3/. Data are given for the vaporization of Al/sub 2/O)/sub 3/ in tungsten to yield Al, AlO, Al/sub 2/O, and WO/sub 2/. More information will be needed before thermodynamic calculations can be made for this system. The continuously monitered effusion apparatus, the null-point effusion apparatus, the oscillating cup viscometer, and the sessile drop equipment have been constructed and calibrated. The viscosity of fused silica was determined at temperatures up te 2560 deg C, where ? = 10/sup 4.4//sup 4/ poises. The viscosity of alumina has been measured using an iridium crucible up to 2200 deg C and determined to be approximately l3 poises. (auth)

• Research Organization: Avco Corp. Research and Advanced Development Div., Wilmington, Mass.
• NSA Number: NSA-15-005380
• OSTI ID: 4111323
• Report Number(s): WADD-TR-60-463(Pt.I)
• Country of Publication: United States
• Language: English

Related Subjects

ALUMINUM
ALUMINUM OXIDES
BEAMS
CRUCIBLES
DIFFUSION
EVAPORATION
EVAPORATION HEAT
FUSED SALTS
HIGH TEMPERATURE
IRIDIUM
KNUDSEN EFFUSION
LABORATORY EQUIPMENT
LIQUEFYING
MASS SPECTROMETERS
MEASURED VALUES
METALS, CERAMICS, AND OTHER MATERIALS
MOLECULES
OSMIUM
QUANTITATIVE ANALYSIS
RHODIUM
SILICON OXIDES
STANDARDS
TARGETS
THERMODYNAMICS
THORIUM OXIDES
TUNGSTEN
TUNGSTEN OXIDES
VISCOSITY