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Mechanical fabrication, heat treatment, and machining of uranium alloys

Description: From conference on physical metallurgy of uranium alloys; Vail, Colorado, USA (12 Feb 1974). A review of the state of the art is presented on the fabrication and properties of U-rich alloys in which the alloying elements are highly miscible in gamma -U (Nb, Zr, Ti, Mo). Processing of both low alloys (which will not retain a metastable gamma phase when quenched) and high alloys (which will retain a metastable gamma phase, usually greater than 6% Mo or Nb) is treated. Forging, extrusion, deep drawing, shear spinning, single-point turning, milling, drilling, tapping, and electrical discharge machining are discussed. Heat treatments (metastable, solution treatment, age hardening) to yield the desired mechanical properties are also discussed. (18 figures, 6 tables, 57 references) (DLC)
Date: January 1, 1974
Creator: Boland, J.F. & Sandstrom, D.J.
Partner: UNT Libraries Government Documents Department

Calculations concerning precipitate growth during impact extrusion

Description: An analysis of carbide particle growth during impact extrusion of 440A stainless steel was made and it was concluded that diffusion enhancements of the order of 8000 or more would be needed to produce particles with 25 A radii under such conditions. Deformation-induced excess vacancy enhanced diffusion was examined for the conditions of impact extrusion and it was learned that significant diffusion enhancement would not occur by this mechanism. Finally, dislocation ''pipe'' diffusion as a possible diffusion enhancement mechanism was evaluated. Although it would appear that ''pipe'' diffusion is capable of providing large enhancements, the experimental results were contradictory to the behavior predicted by the ''pipe'' diffusion model. The overall conclusion is that carbide particles cannot grow to physically meaningful sizes during impact extrusion. (auth)
Date: December 1, 1975
Creator: Scott, T.E.
Partner: UNT Libraries Government Documents Department

Interrelationships between process parameters, structure, and properties of CVD tungsten and tungsten--rhenium alloys

Description: From conference on structure-property relationships in thick film and bulk coatings; San Francisco, California, USA (28 Jan The development of CVD techniques for fabricating free-standing tungsten and tungsten - rhenium alloy structures is reviewed. Relationships between plating parameters, kinetics, morphology, microstructure, and properties of thick polycrystalline deposits are discussed. It is emphasized that porosity may be grown into the grain boundaries when the deposition rate is cortrolled by gas phase diffusion, and that fully dense deposits are generally obtained when the rate is limited by a surface process. The origin and control of many of the microstructural features peculiar to CVD are also discussed. (11 figures) (auth)
Date: December 1, 1973
Creator: Holman, W.R. & Huegel, F.J.
Partner: UNT Libraries Government Documents Department

Calculation of soil hydraulic conductivity from soil--water retention relationships

Description: A computer program has been written to solve the modified Millington and Quirk equation for computing the hydraulic conductivity curve for partially saturated soil from the moisture retention versus suction measurements. This document describes the equation and computer programs. It also shows plots of test results and compares them with physically measured data. (auth)
Date: January 1, 1973
Creator: Reisenauer, A.E.
Partner: UNT Libraries Government Documents Department

Diamond-turning HP-21 beryllium to achieve an optical surface

Description: Investigation of diamond turning on beryllium was made in anticipation of obtaining an optical finish. Although results of past experiences were poor, it was decided to continue diamond turning on beryllium beyond initial failures. By changing speed and using coolant, partial success was achieved. Tool wear was the major problem. Tests were made to establish and plot wear as a function of cutting speed and time. Slower speeds did cause lower wear rates, but at no time did wear reach an acceptable level. The machine, tools, and procedure used were chosen based on the results of preliminary attempts and on previous experience. It was unnecessary to use an air-bearing spindle because tool failure governed the best finish that could be expected. All tools of diamond composition, whether single crystal or polycrystalline, wore at unacceptable rates. Based on present technology, it must be concluded that beryllium cannot be feasibly diamond turned to achieve an optical finish. (22 fig.) (auth)
Date: September 25, 1975
Creator: Allen, D.K.; Hauschildt, H.W. & Bryan, J.B.
Partner: UNT Libraries Government Documents Department

Welding austenitic steel clads for fast reactor fuel pins

Description: ABS>From symposium on fuel and elements for fast reactors; Brussels. Belgium (2 Jul 1973). Developmental programs aimed at fabrication of stainless steelclad PuO/sub 2/ fuel pins are described. Information and data are included on welding fast reactor fuel cans, methods of reducing the incidence of weld cracking, effects of weld stresses, and fuel plug design. (JRD)
Date: January 1, 1973
Creator: Papeleux, P.; Flipot, A.J. & Lafontaine, I.
Partner: UNT Libraries Government Documents Department