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The Boron-Carbon System: Final Technical Report, May 1, 1960 - April 30, 1961

Description: Abstract: The boron-carbon equilibrium diagram has been determined by X-ray, metallographic, and thermal analysis of sintered and arc-cast alloys. A single carbide having a range of solubility from approximately 9 to 20 a/o carbon and melting congruently exists in the system. The terminal solubility of carbon in boron is 0.1-0.2a/o. The freezing reaction at the composition and melting temperature of elemental boron; there is a eutectic reaction at 29a/o carbon and 2375 degrees Celcius. No allotropy of boron was observed.
Date: June 7, 1961
Creator: Elliott, Rodney P.

The Boron-Carbon System: Quarterly Report Number 1, May - June 1960

Description: Abstract: A definitive investigation of the boron-carbon equilibrium system is being made by X-ray diffraction, metallographic, and thermal analytical techniques. Alloys are being produced by sintering pressed powder aggregates with subsequent arc melting. Alloys have been made at two atomic percent intervals up to thirty atomic per cent carbon. In the future, higher carbon compositions are to be investigated. Techniques have been worked out for the metallographic preparation of the extremely hard and friable alloys.
Date: August 5, 1960
Creator: Elliott, Rodney P. & Van Thyne, R. J.

The Boron-Carbon System: Quarterly Report Number 2, August - October 1960

Description: Abstract: A definitive investigation of the boron-carbon equilibrium system is being made by X-ray diffraction, metallographic, and thermal analytical techniques. Additional baron-carbon alloys have been prepared by sintering and arc-melting compacts prepared from boron and high-purity graphite. Metallographic examinations of these alloys are in agreement with alloys previously preapred from lampblack. X-ray investigation of sintered compacts indicates that the solubility range of boron carbide extends almost to pure boron. Boron of various purities has been annealed for times up to four hours, but no structure other than beta-rhombohedral has been detected. Very high purity boron (10 ppm impurity) has been obtained for the study of allotropy and the equilibrium relationships at very dilute carbon contents.
Date: November 8, 1960
Creator: Elliott, Rodney P. & Van Thyne, R. J.

The Boron-Carbon System: Quarterly Report Number 3, November 1960 - January 1961

Description: Abstract: A definitive investigation of the boron-carbon equilibrium system is being made by X-ray diffraction, metallographic, and thermal analytical techniques. On the basis of metallographic and X-ray diffraction studies it is concluded that boron carbide has a range of solubility from approximately 10 to 20 atomic per cent carbon at 1500 degrees to 2000 degrees Celsius. The melting point of the carbide-graphite eutectic has been established as 2325-2350 degrees Celsius. No reversible allotropy of the beta-rhombohedral structure has been observed. The solubility of carbon in boron is very small. The melting point of dilute carbon alloys is found to be essentially the same as that of pure boron (2040 degrees to 2050 degrees). No metallographic evidence of a three-phase reaction of dilute alloys is observed.
Date: February 6, 1961
Creator: Elliott, Rodney P.

Contaminant Effects Study : Phase Report, January 5 to September 15, 1962

Description: From abstract: "This report describes and evaluates the variables affecting contamination of precise devices...In the present report these variables are discussed in more detail and the basis for their inclusion in the listing are given. The relative importance of the several parameters will be discussed in another report."
Date: October 9, 1962
Creator: Lieberman, A.

Delayed Failure Hydrogen Embrittlement of Zirconium: Quarterly Report Number 1, September - December 1961

Description: Abstract: "The purpose of this investigation is to determine the extent to which zirconium exhibits delayed failure (static fatigue) as caused by a combination of absorbed hydrogen and applied stress. Both notched and unnotched specimens of unalloyed zirconium and Zircaloy-2 are being initially hydrogenated to 200 ppm by means of a modified Sieverts apparatus, and delayed failure studies are proceeding at room-temperature. Thus far only preliminary data on unnotched, unalloyed zirconium are available; at the 200 ppm hydrogen level, this material appears to be relatively insensitive to delayed failure at room-temperature."
Date: January 3, 1962
Creator: Weinstein, Daniel & Holtz, F. C.

Delayed Failure Hydrogen Embrittlement of Zirconium: Quarterly Report Number 2, December 1961 - March 1962

Description: Abstract: "The purpose of this investigation is to determine the extent to which zirconium and zirconium alloys exhibit delayed failure (static fatigue) as caused by a combination of absorbed hydrogen and applied stress. Both notched and unnotched specimens of unalloyed zirconium and Zircaloy-2 have been hydrogenated to 200 ppm by means of a modified Sieverts apparatus; specimens were evaluated at room temperature. Thus far, no time-dependent fracture has been observed which can be attributed to the delayed failure phenomenon; it appears that these materials are relatively insensitive to static fatigue. The effects of grain size, temperature, cold deformation, and superheated water and steam corrosion on susceptibility to delayed failure are being determined."
Date: March 30, 1962
Creator: Weinstein, Daniel & Holtz, F. C.

Delayed Failure Hydrogen Embrittlement of Zirconium : Summary Report, September 15, 1961 to September 14, 1962

Description: The following report summarizes an investigation made to determine the extent to which zirconium and zirconium alloys exhibit delayed failure as caused by a combination of absorbed hydrogen and applied stress during the period September 15, 1961, to September 14, 1962.
Date: October 10, 1962
Creator: Weinstein, Daniel & Holtz, F. C.

Development and Evaluation of High-Temperature Tungsten Alloys : Final Report, October 1, 1960 - September 30, 1960

Description: This report summarizes investigations taken between October 1, 1959, to September 30, 1960 with the objectives of developing high-tungsten alloys which are readily fabricable into massive and complex shapes and which possess adequate strength for operation at temperatures up to 2000 F. Within this report, studies are divided into two main categories: alloy development and material fabrication techniques
Date: December 14, 1960
Creator: Holtz, F. C. & Van Thyne, R. J.

Development and Evaluation of High-Temperature Tungsten Alloys : Summary Report

Description: Abstract: "Tungsten-rich alloys, developed for use at temperatures up to 2000F, exhibit ductility, fabricability and joinability not found in commercially-available materials. An envelope type of microstructure was produced in compositions containing at least 90 wt% tungsten by liquid-phase sintering of cold-pressed powders in hydrogen. At room temperature the alloys could be rolled extensively, and tensile elongations up to 25% were noted. Strength properties of a W-Ni-Fe base were improved by small quaternary additions. The ultimate tensile strength of a 90W-4.8Ni-3.2Fe-2Ru alloy was 46,700 psi at 2000F, compared to 30,000 - 35,000 psi for unalloyed tungsten or W-Ni-Fe; the 100-hour stress-rupture strength at 1600F was 15,000 psi. Excellent joints were produced by spot welding and localized induction heating. The oxidation resistance of unprotected 90 wt% tungsten compositions was not significantly affected by alloying."
Date: November 12, 1959
Creator: Holtz, F. C. & Van Thyne, R. J.

Electrostatic Classification of Submicron Airborne Particles : Final Report, August 16, 1961 to January 31, 1963

Description: From abstract: "This project was a study of electrostatic classification of submicron aerosols. Classification of particles as small as 0.006-[mu]-diameter was shown to be feasible, and good classification of atmospheric dust was achieved. However, a practical solution to the problem of overlapping between particles larger and smaller than 0.1 [mu], the point of minimum electric mobility, was not found."
Date: January 31, 1963
Creator: Langer, G.

Electrostatic Classification of Submicron Airborne Particles : Progress report, April 1 to June 1, 1962

Description: The following report focuses on the study of electrostatic classification of submicron aerosols, with emphasis on particles below 0.1 micron. During the period this work was concerned with detailed studies of the ARF charger, the Whitby ionizer used as a charger or neutralizer, and the high-volume classifier.
Date: 1962
Creator: Langer, G.

Electrostatic Classification of Submicron Airborne Particles : Progress Report, April 15 to June 15, 1961

Description: Abstract: "This program is a study of the basic variables that affect electrostatic classification of heterogeneous aerosols of submicron size,especially below 0.1[mu]. The variables of interest are particle size, concentration, composition, shape, and initial charge. During this period research was concerned with classifying particles as small as 0.01[mu]. This research included work on an aerosol generator for monodispersed 0.015-[mu] gold particles. The performance of the charger was further improved by studying its basic electrical characteristics. Tests with the electrostatic classifier showed very clearly the interference due to the stabilizer material associated with polystyrene latex suspensions. These suspensions are used to produce monodispersed aerosols for calibration."
Date: 1961
Creator: Langer, G.

Electrostatic Classification of Submicron Airborne Particles : Progress Report, August 1 to October 1, 1962

Description: Introduction: "This study is concerned with the classification of submicron aerosols by electrostatic means. The controlled charging of the particles without undue aerosol losses is of principal interest. We are investigating means of eliminating the interference due to the deposition of small and large particles in the same area. The sampler is to be developed to classify atmospheric dust particles at a rate approaching 1 cfm. During the period covered by this report, work was concerned with the charger and with bringing the high-volume classifier into routing operation. Further tests were made on the classification of atmospheric dust."
Date: 1962
Creator: Langer, G.