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Tantalum-Rich Alloys of Tuballoy

Description: Report discussing "methods for the manufacture of refractory crucibles for use in high temperature work in general." Additionally, "preliminary experiments with the induction furnace to test the action of tantalum on tantalum carbide at 2900°C are described."
Date: January 15, 1946
Creator: Sausville, J. W. & Larson, C. E.
Partner: UNT Libraries Government Documents Department

One-piece, composite crucible with integral withdrawal/discharge section

Description: A one-piece, composite open-bottom casting mold with integral withdrawal section is fabricated by thermal spraying of materials compatible with and used for the continuous casting of shaped products of reactive metals and alloys such as, for example, titanium and its alloys or for the gas atomization thereof.
Date: July 30, 2002
Creator: Besser, Matthew (Iowa State Univ., Ames, IA); Terpstra, Robert L. (Iowa State Univ., Ames, IA); Sordelet, Daniel J. (Iowa State Univ., Ames, IA); Anderson, Iver E. (Iowa State Univ., Ames, IA); Hartman, Alan D.; Argetsinger, Edward R. et al.
Partner: UNT Libraries Government Documents Department

Complex Adaptive Systems of Systems (CASoS) engineering and foundations for global design.

Description: Complex Adaptive Systems of Systems, or CASoS, are vastly complex ecological, sociological, economic and/or technical systems which must be recognized and reckoned with to design a secure future for the nation and the world. Design within CASoS requires the fostering of a new discipline, CASoS Engineering, and the building of capability to support it. Towards this primary objective, we created the Phoenix Pilot as a crucible from which systemization of the new discipline could emerge. Using a wide range of applications, Phoenix has begun building both theoretical foundations and capability for: the integration of Applications to continuously build common understanding and capability; a Framework for defining problems, designing and testing solutions, and actualizing these solutions within the CASoS of interest; and an engineering Environment required for 'the doing' of CASoS Engineering. In a secondary objective, we applied CASoS Engineering principles to begin to build a foundation for design in context of Global CASoS
Date: January 1, 2012
Creator: Brodsky, Nancy S.; Finley, Patrick D.; Beyeler, Walter Eugene; Brown, Theresa Jean; Linebarger, John Michael; Moore, Thomas W. et al.
Partner: UNT Libraries Government Documents Department

Processing of Special Metal for Hanford

Description: The object of this project is to reduce the impurities and raise the density of rejected slugs and briquetted turnings from these slugs by recasting the material. Summary and conclusions are (1) slugs and briquettes made from turnings produced when these slugs were machined can be recast with great improvement in quality; (2) casting this material is quite hard on graphite crucibles, but a long-range program might point the way to better graphite usage; (3) this metal run alone gives fair yields (88.8% to 94.8%) if heated to 2500 F and then cooled to 2400 F before pouring. Mixing with virgin metal improves the final quality, but does not materially increase the yield; (4) briquettes should not be mixed with magnesium before recasting.
Date: March 10, 1947
Creator: Oppold, William A.
Partner: UNT Libraries Government Documents Department

Canyon dissolution of sand, slag, and crucible residues

Description: An alternative to the FB-Line scrap recovery dissolver was desired for the dissolution of sand, slag, and crucible (SS{ampersand}C) residues from the plutonium reduction process due to the potential generation of hydrogen gas concentrations above the lower flammability limit. To address this concern, a flowsheet was developed for the F-Canyon dissolvers. The dissolvers are continually purged with nominally 33 SCFM of air; therefore the generation of flammable gas concentrations should not be a concern. Following removal of crucible fragments, small batches of the remaining sand fines or slag chunks containing less than approximately 350 grams of plutonium can be dissolved using the center insert in each of the four annular dissolver ports to address nuclear criticality safety concerns. Complete dissolution of the sand fines and slag chunks was achieved in laboratory experiments by heating between 75 and 85 degrees Celsius in a 9.3M nitric acid/0.013M (hydrogen) fluoride solution. Under these conditions, the sand and slag samples dissolved between 1 and 3 hours. Complete dissolution of plutonium and calcium fluorides in the slag required adjusting the dissolver solution to 7.5 wt% aluminum nitrate nonahydrate (ANN). Once ANN was added to a dissolver solution, further dissolution of any plutonium oxide (PuO2) in successive charges was not practical due to complexation of the fluoride by aluminum. During the laboratory experiments, well mixed solutions were necessary to achieve rapid dissolution rates. When agitation was not provided, sand fines dissolved very slowly. Measurement of the hydrogen gas generation rate during dissolution of slag samples was used to estimate the amount of metal in the chunks. Depending upon the yield of the reduction, the values ranged between approximately 1 (good yield) and 20% (poor yield). Aging of the slag will reduce the potential for hydrogen generation as calcium metal oxidizes over time. The potential for excessive ...
Date: December 1, 1997
Creator: Rudisill, T.S.; Gray, J.H.; Karraker, D.G. & Chandler, G.T.
Partner: UNT Libraries Government Documents Department

CSER 96-013: Cementation Process, glovebox HA-20MB at PFP

Description: This evaluation provides criticality safety controls for the cementation processing in Glovebox HA-2OMB at the Plutonium Finishing Plant. Slag and crucible residues from Pu button making will be blended with Portland cement in 5k-in. diam. x 7-in. tall cans, for eventual disposition in special DOT 17C drums. A maximum of 180 g Pu is allowed per liquid-bearing container (mixing bowl, filter funnel, or cement can). In this SD revision, three separate areas with 500 g Pu limits each are established; the airlock cell for input S&C cans, the reaction- and mixing-process area, and a cemented-can storage area. Number and spacing of containers within an area is not restricted, for areas spaced 6 inches apart. Acid addition in the reaction stage is allowed to the extent that plutonium dissolution will not occur.
Date: September 1, 1996
Creator: Hess, A.L.
Partner: UNT Libraries Government Documents Department

Flowsheet modifications for dissolution of sand, slag, and crucible residues in the F-canyon dissolvers

Description: An initial flowsheet for the dissolution of sand, slag, and crucible (SS{ampersand}C) was developed for the F- Canyon dissolvers as an alternative to dissolution in FB-Line. In that flowsheet, the sand fines were separated from the slag chunks and crucible fragments. Those two SS{ampersand}C streams were packaged separately in mild-steel cans for dissolution in the 6.4D dissolver. Nuclear safety constraints limited the dissolver charge to approximately 350 grams of plutonium in two of the three wells of the dissolver insert and required 0.23M (molar) boron as a soluble neutron poison in the 9.3M nitric acid/0.013M fluoride dissolver solution. During the first dissolution of SS{ampersand}C fines, it became apparent that a significant amount of the plutonium charged to the 6.4D dissolver did not dissolve in the time predicted by previous laboratory experiments. The extended dissolution time was attributed to fluoride complexation by boron. An extensive research and development (R{ampersand}D) program was initiated to investigate the dissolution chemistry and the physical configuration of the dissolver insert to understand what flowsheet modifications were needed to achieve a viable dissolution process.
Date: December 1, 1997
Creator: Rudisill, T.S.; Karraker, D.G. & Graham, F.R.
Partner: UNT Libraries Government Documents Department

Apparatus and Method for Increasing the Diameter of Metal Alloy Wires Within a Molten Metal Pool

Description: In a dip forming process the core material to be coated is introduced directly into a source block of coating material eliminating the need for a bushing entrance component. The process containment vessel or crucible is heated so that only a portion of the coating material becomes molten, leaving a solid portion of material as the entrance port of, and seal around, the core material. The crucible can contain molten and solid metals and is especially useful when coating core material with reactive metals. The source block of coating material has been machined to include a close tolerance hole of a size and shape to closely fit the core material. The core material moves first through the solid portion of the source block of coating material where the close tolerance hole has been machined, then through a solid/molten interface, and finally through the molten phase where the diameter of the core material is increased. The crucible may or may not require water-cooling depending upon the type of material used in crucible construction. The system may operate under vacuum, partial vacuum, atmospheric pressure, or positive pressure depending upon the type of source material being used.
Date: January 29, 2002
Creator: Hartman, Alan D.; Argetsinger, Edward R.; Hansen, Jeffrey S.; Paige, Jack I.; King, Paul E. & Turner, Paul C.
Partner: UNT Libraries Government Documents Department

BRIQUETTING OF MACHINED PLUTONIUM TURNINGS FOR RECYCLE TO THE CASTING OPERATION. Final Report-Production Test 235-6

Description: Twenty-four briquettes of Pu turnings were pressed in a He atmosphere and made into eight castings. Six castings were processed to final form and were comparable to normally processed material. Two castings were recy-cled due to causes other than briquetting. Casting y-ieids. (wt. of casting/wt. of briquettes). were approximately 90%; approximately 10% of the Pu in the briquettes remaining in the melting and pouring crucible as skull. (auth)
Date: November 7, 1952
Creator: Chandler, B. A.
Partner: UNT Libraries Government Documents Department

BOTTOM-POUR RE-USABLE MELTING CRUCIBLES FOR PLUTONIUM CASTING

Description: 24p. Bottom-pour Ta and CaF/sub 2/-coated steel melt crucibles for Pu and Pu-rich alloys were developed. The controlled pour is effected by melting a Pu plug in the bottom spout of the crucible after the desired temperature and vacuum conditions are obtained. A description is given of the development of the crucibles which have replaced ceramic crucibles for casting work on the kilogram scale. (auth)
Date: October 1, 1960
Creator: Miley, F. & Anderson, J.W.
Partner: UNT Libraries Government Documents Department

AVNG as a Test Case for Cooperative Design

Description: Designing a measurement system that might be used in a nuclear facility is a challenging, if not daunting, proposition. The situation is made more complicated when the system needs to be designed to satisfy the disparate requirements of a monitoring and a host party - a relationship that could prove to be adversarial. The cooperative design of the elements of the AVNG (Attribute Verification with Neutrons and Gamma Rays) system served as a crucible that exercised the possible pitfalls in the design and implementation of a measurement system that could be used in a host party nuclear facility that satisfied the constraints of operation for both the host and monitoring parties. Some of the issues that needed to be addressed in the joint design were certification requirements of the host party and the authentication requirements of the monitoring party. In this paper the nature of the problem of cooperative design will be introduced. The details of cooperative design revolve around the idiosyncratic nature of the adversarial relationship between the parties involved in a possible measurement regime, particularly if measurements on items that may contain sensitive information are being pursued. The possibility of an adversarial interaction is more likely if an information barrier is required for the measurement system. The origin of the antagonistic elements of the host party and hosted party relationship will be considered. In addition, some of the conclusions will be presented that make cooperative design (and development) proceed more efficiently. Finally, some lessons learned will be presented as a result of this expedition into cooperative design.
Date: May 21, 2010
Creator: Luke, S J
Partner: UNT Libraries Government Documents Department

Studies on the scale-up of the microwave-assisted nitridation and sintering of reaction-bonded silicon nitride

Description: Studies using laboratory test samples have shown that microwave heating produces sintered reaction-bonded silicon nitride materials with improved properties. The final challenge for processing this material by microwave heating is the development of a technology for processing larger batch-size quantities of these materials. Initial microwave scale-up experiments were performed using powder compacts of a bucket tappet geometry. In experiments using microwave-transparent boron nitride sample crucibles, temperature gradients within some crucibles led to larger variations in the sample densities than were obtained with the conventionally processed samples. The use of a microwave-suscepter type crucible made of silicon carbide and boron nitride resulted in an improved temperature uniformity and in density variations comparable to those obtained for the control groups.
Date: May 1, 1996
Creator: Kiggans, J.O.: Tiegs, T.N. & Kimrey, H.D.
Partner: UNT Libraries Government Documents Department

Purex Processing of Dissolved Sand, Slag, and Crucible Containing High Levels of Boric Acid and Calcium Fluoride

Description: The plutonium solution obtained from the dissolution of SSC in F- Canyon will be high in fluoride. Flowsheet adjustments must be made to increase the plutonium extraction in the solvent extraction cycle to keep Pu losses from being excessive.
Date: May 1, 1998
Creator: Kyser, E.A.
Partner: UNT Libraries Government Documents Department

Directly Susceptible, Noncarbon Composite Crucible

Description: A sintered metal ceramic crucible suitable for high temperature induction melting of reactive metals without appreciable carbon or silicon contamination of the melt. The crucible comprises a cast matrix of a thermally conductive ceramic material; a perforated metal sleeve, which serves as a susceptor for induction heating of the crucible, embedded within the ceramic cast matrix; and a thermal-shock-absorber barrier interposed between the metal sleeve and the ceramic cast matrix to allow for differential thermal expansions between the matrix and the metal sleeve and to act as a thermal-shock-absorber which moderates the effects of rapid changes of sleeve temperature on the matrix.
Date: November 25, 1998
Creator: Holcombe, Cressie E.,Jr.; Kiggans, James O., Jr.; Morrow, Marvin S. & Rexford, Donald
Partner: UNT Libraries Government Documents Department