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Plastic Flow During Extrusion of Tubing

Description: Abstract: "A study of plastic flow during the extrusion of tubing was made by extruding colored Plasticine billets in a small-scale extrusion press. Decreasing the included angle of the conical die and tapering the ram end of the billet decreased the amount of coextrusion of the backer block into the tubing, lubricating the billet also decreased coextrusion."
Date: July 26, 1955
Creator: Saller, Henry A.; Keeler, John R. & Cuddy, Lee J.
Partner: UNT Libraries Government Documents Department

The Extrusion of Beryllium

Description: Abstract: "A method for the extrusion of beryllium into rods and tubing has been developed. The operation is carried out between 1500 and 1900 F and the billet is clad in a layer of soft iron to prevent contact between it and the die steals. Extruded beryllium has much more strength and ductility than cast metal due to the crystal refinement which occurs as a result of the fabrication operation."
Date: 1950
Creator: Creutz, Edward Chester, {}
Partner: UNT Libraries Government Documents Department

A Study of Fabricating Beryllia by Cold Compaction and Extrusion Techniques

Description: From introduction: "This report presents the results of the preliminary studies of two fabrication methods aimed at producing high density beryllia shapes more economically. The method were cold compaction and sintering, and extrusion and sintering."
Date: July 1958
Creator: Harkulich, Theodore M. & Higbie, Kenneth B.
Partner: UNT Libraries Government Documents Department

Interparticle movement and the mechanical behavior of extruded powder aluminum at elevated temperature

Description: This paper proposes a model and mechanism, based on relative motion of the extruded aluminum particles, to explain these effects. Quantitative stereology is used to support the concept. Stress-strain relations are derived for the uniaxial and biaxial behavior of powder aluminum and they are seen to fit the data from a number of uniaxial and tension-torsion test specimens. Implications of the model for forming of extruded powder metal products are discussed
Date: September 1, 1996
Creator: Peacock, H.B.
Partner: UNT Libraries Government Documents Department

Oxide Dispersion Strengthened Fe(sub 3)Al-Based Alloy Tubes: Application Specific Development for the Power Generation Industry

Description: A detailed and comprehensive research and development methodology is being prescribed to produce Oxide Dispersion Strengthened (ODS)-Fe3Al thin walled tubes, using powder extrusion methodologies, for eventual use at operating temperatures of up to 1100C in the power generation industry. A particular 'in service application' anomaly of Fe3Al-based alloys is that the environmental resistance is maintained up to 1200C, well beyond where such alloys retain sufficient mechanical strength. Grain boundary creep processes at such high temperatures are anticipated to be the dominant failure mechanism.
Date: July 1, 1999
Creator: Kad, B.K.
Partner: UNT Libraries Government Documents Department

Plant-Wide Assessment Report for Shaw Industries, Plant #78; Aiken, SC

Description: A plant-wide energy assessment sponsored by the U.S. Department of Energy was conducted at Shaw Industries Group, plant #78 in Aiken, SC. The assessment team consisted of Georgia Tech faculty from the Energy & Environmental Management Center and Shaw personnel from plant #78 and the corporate energy group. The purpose of this assessment was to uncover as many opportunities for saving energy usage and costs using techniques that have been established as best practices in the energy engineering field. In addition, these findings are to be shared with similar plants in Shaw Industries Group to multiply the lessons learned. The findings from this assessment are included in this report.
Date: April 10, 2006
Creator: Michael Brown PE, CEM; Soderlund, Matt; PE, Bill Meffert; Baldisserotto, Paolo & Jerry Zolkowski PE, CEM
Partner: UNT Libraries Government Documents Department

Multilayer co-extrusion technique for developing high energy density organic devices.

Description: The purpose of this project is to develop multi-layered co-extrusion (MLCE) capabilities at Sandia National Laboratories to produce multifunctional polymeric structures. Multi-layered structures containing layers of alternating electrical, mechanical, optical, or structural properties can be applied to a variety of potential applications including energy storage, optics, sensors, mechanical, and barrier applications relevant to the internal and external community. To obtain the desired properties, fillers must be added to the polymer materials that are much smaller than the end layer thickness. We developed two filled polymer systems, one for conductive layers and one for dielectric layers and demonstrated the potential for using MLCE to manufacture capacitors. We also developed numerical models to help determine the material and processing parameters that impact processing and layer stability.
Date: November 1, 2009
Creator: Spangler, Scott W.; Schroeder, John Lee; Mrozek, Randy (Army Research Lab, Adelphi, MD); Bieg, Lothar Franz; Rao, Rekha Ranjana; Lenhart, Joseph Ludlow (Army Research Lab, Adelphi, MD) et al.
Partner: UNT Libraries Government Documents Department

Coal log pipeline research at University of Missouri. 3rd quarterly report for 1995, July 1, 1995--September 30, 1995

Description: During this quarter (1/1/95-9/30/95), major progress has been made in the following areas of coal log pipeline research, development and technology transfer: (1) Conceptual design of a test machine based on hydraulic presses to mass-produce 5.4-inch-diameter coal logs for testing in a 6-inch-diameter pipeline has been completed. (2) Conceptual design of a rotary-press machine to produce 1.9-inch-diameter coal logs for testing in a 2-inch-diameter pipeline has also been completed. (3) It has been confirmed through experiments that molds with round-edge exit can make logs as good as those made with tapered exit. (4) Conducted a study to determine the effect of surface condition of mold and lubricants on the quality of coal logs. (5) Completed an evaluation of the effect of fiber (wood pulp) on coal log quality. (6) Prepared an apparatus for testing fast compaction of coal logs -- 2 second per log. (7) Compacted coal logs in a 5.3-inch-diameter mold. (8) Completed a preliminary study to assess vacuum and steam heating systems to enhance coal log production and quality. (9) Changed the small-scale-CLP-demo loop from a once-through system to a recirculating system. (10) Completed revision of CLP economic model and revised the 1993 report.
Date: December 31, 1995
Creator: Liu, H.
Partner: UNT Libraries Government Documents Department

Effect of Extrusion Temperature on the Microstructural Development of Powder Metallurgy Ti-47A1-2Cr-1Nb-1Ta Alloy

Description: Effect of extrusion temperatures on the microstructural development of a powder metallurgy (PM) Ti-47Al-2Cr-1Nb-1Ta (at. %) alloy has been investigated. Microstructure of the PM alloy extruded at 1150 C consists of a fine-grained ({gamma} + {alpha}{sub 2}) two-phase structure in association with coarse grains of metastable B2 (ordered bcc) phase. In addition, fine {omega} (ordered hexagonal) particles are also found within some B2 grains. The PM alloy containing the metastable B2 grains displays a low-temperature superplastic behavior, in which a tensile elongation of 310% is obtained at 800 C under a strain rate of 2 x 10{sup -5} s{sup -1}. It is suggested that the decomposition of metastable B2 phase and microstructural evolution during the deformation play a crucial role in the low-temperature superplasticity of the PM TiAl alloy. A refined fully-lamellar (FL) microstructure with alternating {gamma} and {alpha}{sub 2} lamellae is developed within the PM alloy extruded at 1400 C. The creep resistance of the refined FL-TiAl alloy is found to be superior to those of the TiAl alloys fabricated by conventional processing techniques. Creep mechanisms for the PM alloy with a refined FL microstructure are critically discussed according to TEM examination of deformation substructure.
Date: June 29, 2000
Creator: Hsiung, L. & Nieh, T.G.
Partner: UNT Libraries Government Documents Department

Extrudable explosives. Quarterly report, October--December, 1971

Description: Several extrudable HE formulations using, principally, HNAB as the explosive component were examined in efforts to develop an extrudable composition more temperature-resistant than Extex. It is shown that extrudability is dependent upon particle character, wetting of the binder compound, roll-milling technique and the addition of fine metallic oxides to improve flow properties, while detonability is dependent upon explosive concentration, a hard cure, and the shock parameters of the confining media.
Date: December 31, 1972
Creator: Warren, T.W. & Irion, C.E.
Partner: UNT Libraries Government Documents Department

Mechanism of Ultrafine Grain Formation During Intense Plastic Straining in an Aluminum Alloy at Intermediate Temperatures

Description: The mechanism of grain formation during equal channel angular extrusion (ECAE) in a 2219 Al alloy has been studied at intermediate and high temperatures. It was shown that continuous dynamic recrystallization (CDRX) occurred during intense plastic straining and resulted in the formation of submicrometer grains at temperatures ranging from 250 C to 300 C. Higher temperatures (< 300 C) hindered CDRX. This is caused by the fact that nucleation controls CDRX in the aluminum alloy. Dislocation rearrangements result in the formation of low angle boundary networks at moderate strain. The density of lattice dislocations determines the rate of subgrain formation. In addition, at lower temperatures a low energy dislocation structure (LEDS) forms concurrently with the subgrain structure and stabilizes it. The stability of the subgrain structure is very important for the resulting conversion of low angle boundaries into high angle ones with strain by extensive accumulation of mobile lattice dislocations. Increasing temperature in the range of intermediate temperatures suppresses LEDS formation and decreases the lattice dislocation density. This reduces the rate of the subgrain formation process and CDRX. As a result, at T = 400 C no recrystallized grains were found. At T = 475 C, the new grains form due to geometric dynamic recrystallization (GRX).
Date: September 21, 2000
Creator: Kaibyshev, R.; Sitdikov, O.; Mazurina, I, & Lesuer, D. R.
Partner: UNT Libraries Government Documents Department

Development of advanced fibrous monoliths - final report for project of 1998-2000.

Description: Efforts to develop fibrous ceramic monoliths for primarily structural applications are described. Fibrous monoliths (FMs) are relatively insensitive to flaws and can exhibit graceful failure and large work-of-fracture values. They can be inexpensively produced in a wide variety of forms by conventional ceramic processing methods such as extrusion. The FM project that is the subject of this report involved investigations to (1) develop FMs that can be pressureless sintered rather than hot pressed, (2) develop technologies to continuously extrude FM filaments and inexpensively fabricate FM components, (3) evaluate the performance of commercial and new, prototype FMs, (4) develop micromechanical models to guide the design of new FMs and predict their properties, and (5) forge collaborations with industry to produce useful parts.
Date: May 10, 2001
Creator: Goretta, K. C.; Singh, D.; Cruse, T. A.; Ellingson, W. A.; Picciolo, J. J.; Polzin, B. J. et al.
Partner: UNT Libraries Government Documents Department

PROPERTIES AND NANOSTRUCTURES OF NANO-MATERIALS PROCESSED BY SEVERE PLASTIC DEFORMATION (SPD)

Description: Metallic materials usually exhibit higher strength but lower ductility after being plastically deformed by conventional techniques such as rolling, drawing and extrusion. In contrast, nanostructured metals and alloys processed by severe plastic deformation (SPD) have demonstrated both high strength and high ductility. This extraordinary mechanical behavior is attributed to the unique nanostructures generated by SPD processing. The combination of ultrafine grain size and high-density dislocations appears to enable deformation by new mechanisms not active in coarse-grained metals and alloys. These results demonstrate the possibility of tailoring the microstructures of metals and alloys by SPD to obtain superior mechanical properties. Nanostructured metals and alloys processed by SPD techniques have unique nanostructures not observed in nano-materials synthesized by other techniques such as the consolidation of nanopowders. The SPD-generated nanostructures have many features related to deformation, including high dislocation densities, and high- and low-angle grain boundaries in equilibrium or non-equilibrium states. Future studies are needed to investigate the deformation mechanisms that relate the unique nanostructures with the superior mechanical properties exhibited by SPD-processed metals and alloys.
Date: March 1, 2001
Creator: ZHU, Y. T.
Partner: UNT Libraries Government Documents Department

Polyethylene macroencapsulation - mixed waste focus area. OST reference No. 30

Description: The lead waste inventory throughout the US Department of Energy (DOE) complex has been estimated between 17 million and 24 million kilograms. Decontamination of at least a portion of the lead is viable but at a substantial cost. Because of various problems with decontamination and its limited applicability and the lack of a treatment and disposal method, the current practice is indefinite storage, which is costly and often unacceptable to regulators. Macroencapsulation is an approved immobilization technology used to treat radioactively contaminated lead solids and mixed waste debris. (Mixed waste is waste materials containing both radioactive and hazardous components). DOE has funded development of a polyethylene extrusion macroencapsulation process at Brookhaven National Laboratory (BNL) that produces a durable, leach-resistant waste form. This innovative macroencapsulation technology uses commercially available single-crew extruders to melt, convey, and extrude molten polyethylene into a waste container in which mixed waste lead and debris are suspended or supported. After cooling to room temperature, the polyethylene forms a low-permeability barrier between the waste and the leaching media.
Date: February 1, 1998
Partner: UNT Libraries Government Documents Department

Extruded plastic scintillation detectors

Description: As a way to lower the cost of plastic scintillation detectors, commercially available polystyrene pellets have been used in the production of scintillating materials that can be extruded into different profiles. The selection of the raw materials is discussed. Two techniques to add wavelength shifting dopants to polystyrene pellets and to extrude plastic scintillating strips are described. Data on light yield and transmittance measurements are presented.
Date: April 16, 1999
Creator: Anna Pla-Dalmau, Alan D. Bross and Kerry L. Mellott
Partner: UNT Libraries Government Documents Department

Processing of Mo-Si-B intermetallics by extrusion and oxidation properties of the extruded Tl-MoSi{sub 2}-MoB System

Description: An extrusion process was developed that is able to consistently produce large quantities of Mo-Si-B rods without the presence of defects. Binder removal from the extruded rods was studied in detail and it was determined that heating rates on the order of 0.02{degree}/minute (1.2{degree}/hour) are necessary to remove the binder without the formation of defects. This low heating rate resulted in debinding times in excess of 70 hours (approximately 3 days). Wicking was investigated as a means to decrease the time necessary for binder removal. Using 0.05{micro}m alumina powder as a wicking agent, binder removal times were reduced to 10 hours with heating rates up to 1{degree}/minute employed without defect formation. Once the extrusion process was complete the oxidation properties of the Tl-MoSi{sub 2}-MoB extruded phase assemblage was investigated. It was determined that this composition exhibits catastrophic oxidation or pesting in the temperature range of 660--760 C, resulting in the material turning to dust. Outside of this temperature range the composition is oxidatively stable. Continuous mass measurements were taken at 1,300, 1,450, and 1,600 C to determine the oxidation rate constants of this material. Parabolic rate constants of 6.9 x 10{sup {minus}3}, 1.3 x 10{sup {minus}3}, and 9.1 x 10{sup {minus}3} mg{sup 2}/cm{sup 4}/hr were determined for 1,300, 1,450, and 1,600 C respectively.
Date: November 8, 1999
Creator: Summers, Eric
Partner: UNT Libraries Government Documents Department

Extrusion of I&E ``O`` size tubing to finalize the process. Experiment No. U-31

Description: Work has been progressing on the development of an extrusion process for I&E tubing. The ultimate object of this development project is to compare the extrusion process from a cost standpoint with, the presently used rolling-drilling process. Various experiments have been performed to determine the optimum billet I.D., the proper follower block technique, the proper tooling parameters for the process, and the proper metallurgical structure of the material for optimum results. This extrusion combines many of the past results as a further determination and refinement of the extrusion process to be used in the final semi-production optimization extrusion. The object of this extrusion was to evaluate the resulted of previous extrusion experiments to determine final process conditions prior to an optimization extrusion.
Date: February 3, 1961
Creator: Frazier, D.S. & Puterbaugh, J.F.
Partner: UNT Libraries Government Documents Department

Development of a Tritium Extruder for ITER Pellet Injection

Description: As part of the International Thermonuclear Experimental Reactor (ITER) plasma fueling development program, Oak Ridge National Laboratory (ORNL) has fabricated a pellet injection system to test the mechanical and thermal properties of extruded tritium. Hydrogenic pellets will be used in ITER to sustain the fusion power in the plasma core and may be crucial in reducing first-wall tritium inventories by a process of "isotopic fueling" in which tritium-rich pellets fuel the burning plasma core and deuterium gas fuels the edge. This repeating single-stage pneumatic pellet injector, called the Tritium-Proof-of-Principle Phase II (TPOP-II) Pellet Injector, has a piston-driven mechanical extruder and is designed to extrude and accelerate hydrogenic pellets sized for the ITER device. The TPOP-II program has the following development goals: evaluate the feasibility of extruding tritium and deuterium-tritium (D-T) mixtures for use in future pellet injection systems; determine the mechanical and thermal properties of tritium and D-T extrusions; integrate, test, and evaluate the extruder in a repeating, single-stage light gas gun that is sized for the ITER application (pellet diameter -7 to 8 mm); evaluate options for recycling propellant and extruder exhaust gas; and evaluate operability and reliability of ITER prototypical fueling systems in an environment of significant tritium inventory that requires secondary and room containment systems. In tests with deuterium feed at ORNL, up to 13 pellets per extrusion have been extruded at rates up to 1 Hz and accelerated to speeds of 1.0 to 1.1 km/s, using hydrogen propellant gas at a supply pressure of 65 bar. Initially, deuterium pellets 7.5 mm in diameter and 11 mm in length were produced-the largest cryogenic pellets produced by the fusion program to date. These pellets represent about a 10% density perturbation to ITER. Subsequently, the extruder nozzle was modified to produce pellets that are almost 7.5-mm right circular cylinders. ...
Date: September 1, 1998
Creator: Gouge, M.J. & Fisher, P.W.
Partner: UNT Libraries Government Documents Department