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in creator/contributor: "Fenske, G.R."

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Fabrication of Small-Orifice Fuel Injectors for Diesel Engines.

Diesel fuel injector nozzles with spray hole diameters of 50-75 {micro}m have been fabricated via electroless nickel plating of conventionally made nozzles. Thick layers of nickel are deposited onto the orifice interior surfaces, reducing the diameter from {approx}200 {micro}m to the target diameter. The nickel plate is hard, smooth, and adherent, and covers the orifice interior surfaces uniformly.

Date: April 8, 2005

Creator: Woodford, J. B. & Fenske, G. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Surface Modification of Tribological Components in Transportation

This paper reviews a number of programs funded through the Engineered Tribological Interfaces (ETI) Task area of the Tribology Program that utilize energetic beams of atoms to enhance the mechanical and microstructural properties of near-surface regions to improve the tribological performance of critical components. The processes used in these programs include techniques based on chemical vapor deposition, physical vapor deposition, and ion implantation. A common feature of these techniques is … more

Date: November 1, 1992

Creator: Fenske, G. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Simulation of the effects of grain boundary fission gas during thermal transients

This report presents the results of an initial set of out-of-cell transient heating experiments performed on unirradiated UO/sub 2/ pellets fabricated to simulate the effect of grain boundary fission gas on fuel swelling and cladding failure. The fabrication involved trapping high-pressure argon on internal pores by sintering annular UO/sub 2/ pellets in a hot isostatic press (HIP). The pellet stack was subjected to two separate transients (DGF83-03A and -03B). Figures show photomicrographs of … more

Date: November 1, 1984

Creator: Fenske, G. R.; Emerson, J. E. & Beiersdorf, B. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Fission gas retention in irradiated metallic fuel

Theoretical calculations and experimental measurements of the quantity of retained fission gas in irradiated metallic fuel (U-5Fs) are presented. The calculations utilize the Booth method to model the steady-state release of gases from fuel grains and a simplified grain-boundary gas model to predict the gas release from intergranular regions. The quantity of gas retained in as-irradiated fuel was determined by collecting the gases released from short segments of EBR-II driver fuel that were mel… more

Date: January 1, 1987

Creator: Fenske, G. R.; Gruber, E. E. & Kramer, J. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Macroscopic behavior of fast reactor fuel subjected to simulated thermal transients

High-speed cinematography has been used to characterize the macroscopic behavior of irradiated and unirradiated fuel subjected to thermal transients prototypical of fast reactor transients. The results demonstrate that as the cladding melts, the fuel can disperse via spallation if the fuel contains in excess of approx. 16 ..mu..moles/gm of fission gas. Once the cladding has melted, the macroscopic behavior (time to failure and dispersive nature) was strongly influenced by the presence of volati… more

Date: June 1, 1983

Creator: Fenske, G.R.; Emerson, J.E. & Savoie, F.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Transient fission gas release during direct electrical heating experiments

The gas release behavior of irradiated EBR-II fuel was observed to be dependent on several factors: the presence of cladding, the retained gas content, and the energy absorbed. Fuel that retained in excess of 16 to 17 ..mu..moles/g of fission gas underwent spallation as the cladding melted and released 22 to 45% of its retained gas, while fuel with retained gas levels below approx. 15 to 16 ..mu..moles/g released less than approx. 9% of its gas as the cladding melted. During subsequent direct e… more

Date: December 1, 1983

Creator: Fenske, G. R.; Emerson, J. E. & Savoie, F. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Clean and cost-effective dry boundary lubricants for aluminum forming.

Preliminary research in our laboratory has demonstrated that boric acid is an effective lubricant with an unusual capacity to reduce sliding fiction (providing friction coefficients as low as 0.02) and wear of metallic and ceramic materials. More recent studies have revealed that water or methanol solutions of boric acid can be used to prepare strongly bonded layers of boric acid on aluminum surfaces. It appears that boric acid molecules have a strong tendency to bond chemically to the naturall… more

Date: December 5, 1997

Creator: Erdemir, A. & Fenske, G. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Tribological performance of diamond and diamondlike carbon films at elevated temperatures

In this study, we investigated the tribological performance of diamond and diamondlike carbon (DLC) films as a function of ambient temperature. Both films were deposited on silicon carbide (SiC) by microwave plasma chemical vapor deposition and ion-beam deposition processes. Tribological tests were performed on a reciprocating wear machine in open air (20 to 30% relative humidity) and under a 10-N load using SiC pins. For the test conditions explored, the steady- state friction coefficients of … more

Date: September 1, 1995

Creator: Erdemir, A. & Fenske, G.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Review of surface-modification programs in the DOE-OTM Tribology Program

The use of surface-modification treatments is a widely accepted practice to reduce the wear and modify the friction behavior of surface regions while maintaining desirable bulk properties (e.g., strength, hardness, thermal conductivity, etc.) of the underlying substrate. These treatments range from conventional diffusion processes such as carburizing steels for case-hardening gears, to advanced non-equilibrium processes such as ion implantation or ion plating. The objective of this task area is… more

Date: February 1, 1991

Creator: Fenske, G.R. & Nichols, F.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Review of surface-modification programs in the DOE-OTM Tribology Program

Date: February 1, 1991

Creator: Fenske, G. R. & Nichols, F. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Preparation of ultralow-friction surface films on vanadium diboride.

In this paper, we present a simple annealing procedure (which we refer to as ''flash-annealing'' because of short duration) that results in the formation of an ultralow friction surface film on vanadium diboride (VB{sub 2}) surfaces. This annealing is done in a box furnace at 800 C for a period of 5 min. During annealing, the exposed surface of the VB{sub 2} undergoes oxidation and forms a layer of boron oxide (B{sub 2}O{sub 3}). In open air, the B{sub 2}O{sub 3} layer reacts spontaneously with… more

Date: October 14, 1996

Creator: Erdemir, A.; Fenske, G. R. & Halter, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dry lubricant films for aluminum forming.

During metal forming process, lubricants are crucial to prevent direct contact, adhesion, transfer and scuffing of workpiece materials and tools. Boric acid films can be firmly adhered to the clean aluminum surfaces by spraying their methanol solutions and provide extremely low friction coefficient (about 0.04). The cohesion strengths of the bonded films vary with the types of aluminum alloys (6061, 6111 and 5754). The sheet metal forming tests indicate that boric acid films and the combined fi… more

Date: March 30, 1999

Creator: Wei, J.; Erdemir, A. & Fenske, G. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Behavior of mixed-oxide fuel subjected to multiple thermal transients

The microstructural behavior of irradiated mixed-oxide fuel subjected to multiple, mild thermal transients was investigated using direct electrical heating. The results demonstrate that significant intergranular porosity, accompanied by large-scale (>90%) release of the retained fission gas, developed as a result of the cyclic heating. Microstructural examination of the fuel indicated that thermal-shock-induced cracking of the fuel contributed significantly to the increased swelling and gas rel… more

Date: November 1, 1983

Creator: Fenske, G.R.; Hofman, G.L.; Neimark, L.A. & Poeppel, R.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Fission gas retention and axial expansion of irradiated metallic fuel

Out-of-reactor experiments utilizing direct electrical heating and infrared heating techniques were performed on irradiated metallic fuel. The results indicate accelerated expansion can occur during thermal transients and that the accelerated expansion is driven by retained fission gases. The results also demonstrate gas retention and, hence, expansion behavior is a function of axial position within the pin.

Date: May 1, 1986

Creator: Fenske, G. R.; Emerson, J. E.; Savoie, F. E. & Johanson, E. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Development of lubricious coatings for advanced turbine engine applications

Development of durable and low-cost high-temperature lubricants for use in gas-turbine regenerator cores is critically important for achieving improved performance and fuel-efficiency in future automotive and hybrid-electric vehicles. Successful development and implementation of such coatings could have substantial technological and economic impacts on energy conservation and could reduce dependence on imported oil. Furthermore, this technology may also contribute to a cleaner environment by re… more

Date: February 1, 1996

Creator: Erdemir, A.; Fenske, G.R. & Munson, J.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Tribological properties of hard carbon films on zirconia ceramics

This study investigated the tribological properties of hard diamondlike carbon (DLC) films on magnesia-partially-stabilized zirconia (MgO-PSZ) substrates over a wide range of loads, speeds, temperatures, and counterface materials. The films were 2 {micro}m-thick and produced on by ion-beam deposition at room temperature. Tribological tests were conducted on a ball-on-disk machine in open air of 30 to 50% relative humidity under contact loads of 1 to 50 N, at sliding velocities of 0.1 to 6 m/s, … more

Date: December 31, 1995

Creator: Erdemir, A.; Bindal, C.; Fenske, G.R. & Wilbur, P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Friction and wear performance of low-friction carbon coatings under oil lubrication.

Amorphous carbon coatings with very low friction properties were recently developed at Argonne National Laboratory. These coatings have shown good promise in mitigating excessive wear and scuffing problems associated with low-lubricity diesel fuels. To reduce the negative effect of sulfur and other lubricant additives in poisoning the after-treatment catalyst, a lubricant formulation with a low level of sulfur may be needed. Exclusion of proven sulfur-containing extreme pressure (EP) and antiwe… more

Date: December 11, 2001

Creator: Kovalchenko, A.; Ajayi, O. O.; Erdemir, A. & Fenske, G. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Multiyear Program Plan: Reducing Friction and Wear in Heavy Vehicles

As described in its multiyear program plan for 1998-2000, the Office of Heavy Vehicle Technologies (OHVT) envisions the development of a fuel-flexible, energy-efficient, near-zero-emissions, heavy-duty U.S. diesel engine technology devolving into all truck classes as a real and viable strategy for reducing energy requirements for commercial transport services and the rapidly growing multipurpose vehicle market (pickups, vans, and sport utility vehicles). Implementation of the OHVT program plan … more

Date: December 13, 1999

Creator: Fessler, R.R. & Fenske, G.R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Analysis of recent fuel-disruption experiments

Recent USDOE-sponsored DEH, FGR, and TREAT F series fuel-disruption experiments are analyzed with existing analytical models. The experiments are interpreted and the results used to evaluate the models. Calculations are presented using the FRAS3 fission-gas-behavior code and the DiMelfi-Deitrich fuel-response model.

Date: January 1, 1982

Creator: Kramer, J. M.; Kraft, T. E.; DiMelfi, R. J.; Fenske, G. R. & Gruber, E. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

High-temperature tribological characteristics of silver and gold coatings on ceramics prepared by ion-beam-assisted deposition

An ion-beam-assisted deposition (IBAD) system was used to deposit silver and gold coatings on polycrystalline {alpha}-alumina (Al{sub 2}O{sub 3}) substrates for tribological studies at temperatures to 400{degrees}C. The wear tests were performed with an oscillating ball-on-flat type of test apparatus as a partial simulation of ring/liner motion and contact geometry in actual engine systems. The test results showed that without a surface coating, both the wear rates and the friction coefficients… more

Date: April 1, 1992

Creator: Erdemir, A.; Erck, R. A.; Fenske, G. R. & Nichols, F. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Effect of thin-film coating on wear in EGR-contaminated oil.

Increased use of higher-efficiency compression ignition direct injection (CIDI) diesel engines instead of today's gasoline engines will result in reduced fuel consumption and greenhouse gases emissions. However, NO{sub x} and particulate exhaust emissions from diesel engines must be significantly reduced due to their possible adverse health effects. Exhaust gas recirculation (EGR) is an effective way to reduce NO{sub x} emissions from diesel engines, but the particulates and acidic exhaust prod… more

Date: December 6, 2001

Creator: Ajayi, O. O.; Aldajah, S. H.; Erdemir, A. & Fenske, G. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Effect of source gas chemistry on tribological performance of diamond-like carbon films.

In this study, we investigated the effects of various source gases (i. e., methane, ethane, ethylene, acetylene and methane + hydrogen) on friction and wear performance of diamond-like carbon (DLC) films. Specifically, we described the anomalous nature and fundamental friction and wear mechanisms of DLC films derived from gas discharge plasmas with very low to very high hydrogen content. The films were deposited on steel substrates by a plasma enhanced chemical vapor deposition process at room … more

Date: August 23, 1999

Creator: Erdemir, A.; Eryilmaz, O. L.; Fenske, G. R. & Nilufer, I. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

High-temperature tribological characteristics of silver and gold coatings on ceramics prepared by ion-beam-assisted deposition

Date: April 1, 1992

Creator: Erdemir, A.; Erck, R.A.; Fenske, G.R. & Nichols, F.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Hydrogen Pipeline Compressors Annual Progress Report.

The objectives are: (1) develop advanced materials and coatings for hydrogen pipeline compressors; (2) achieve greater reliability, greater efficiency, and lower capital in vestment and maintenance costs in hydrogen pipeline compressors; and (3) research existing and novel hydrogen compression technologies that can improve reliability, eliminate contamination, and reduce cost. Compressors are critical components used in the production and delivery of hydrogen. Current reciprocating compressors … more

Date: July 15, 2011

Creator: Fenske, G. R. & Erck, R. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department