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in creator/contributor: "Covino, B.S., Jr."

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Corrosion of Titanium Matrix Composites

The corrosion behavior of unalloyed Ti and titanium matrix composites containing up to 20 vol% of TiC or TiB{sub 2} was determined in deaerated 2 wt% HCl at 50, 70, and 90 degrees C. Corrosion rates were calculated from corrosion currents determined by extrapolation of the tafel slopes. All curves exhibited active-passive behavior but no transpassive region. Corrosion rates for Ti + TiC composites were similar to those for unalloyed Ti except at 90 degrees C where the composites were slightly h… more

Date: September 22, 2002

Creator: Covino, B. S., Jr. & Alman, D. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Corrosion behavior of iron and nickel base alloys under solid oxide fuel cell exposure conditions

Topography and phase composition of the scales formed on commercial ferritic stainless steels and experimental low CTE nickel-based alloys were studied in atmospheres simulating solid oxide fuel cell (SOFC) environments. The materials were studied under dual environment conditions with air on one side of the sample and carbon monoxide on the other side at 750°C. Surface characterization techniques, such as scanning electron microscopy and X-ray diffraction analysis were used in this study.

Date: March 1, 2006

Creator: Ziomek-Moroz, M.; Holcomb, G. R.; Covino, B. S., Jr. & Bullard, S. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Oxidation of advanced steam turbine alloys

Advanced or ultra supercritical (USC) steam power plants offer the promise of higher efficiencies and lower emissions. Current goals of the U.S. Department of Energy’s Advanced Power Systems Initiatives include coal generation at 60% efficiency, which would require steam temperatures of up to 760°C. This research examines the steamside oxidation of advanced alloys for use in USC systems, with emphasis placed on alloys for high- and intermediate-pressure turbine sections.

Date: March 1, 2006

Creator: Holcomb, G. R.; Covino, B. S., Jr.; Bullard, S. J. & Ziomek-Moroz, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Corrosion behavior of experimental and commercial nickel-base alloys in HCl and HCl containing Fe3+

The effects of ferric ions on the corrosion resistance and electrochemical behavior of a series of Ni-based alloys in 20% HCl at 30ºC were investigated. The alloys studied were those prepared by the Albany Research Center (ARC), alloys J5, J12, J13, and those sold commercially, alloys 22, 242, 276, and 2000. Tests included mass loss, potentiodynamic polarization, and linear polarization.

Date: March 1, 2006

Creator: Holcomb, G. R.; Covino, B. S., Jr.; Bullard, S. J. & Ziomek-Moroz, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

Fireside Corrosion in Oxyfuel Combustion Environments,”

Oxy-fired or low-nitrogen combustion is a technology that will facilitate CO2 capture while also reducing NOx formation and which offers the opportunity for near-zero emissions coal combustion via either the retrofit of existing power plants, or the design of new power plants. Because of the opportunity to improve the environmental performance of the existing coal fired fleet (currently approximately 800 GW of capacity in the US alone) and the potential for converting these plants from air-blow… more

Date: March 1, 2009

Creator: Holcomb, G. R.; Matthes, S. A.; Rawers, J. C. & Covino, B. S., Jr.

Item Type: Poster

Partner: UNT Libraries Government Documents Department

open access

Microclimate Corrosion Effects in Coastal Environments

The Albany Research Center is conducting atmospheric corrosion research in coastal environments to improve the performance of materials in the Nation's infrastructure. The corrosion of bare metals, and of painted, thermal-sprayed, and galvanized steels are presented for one-year exposures at sites located on bridges and utility poles along the Oregon coast. The effects of microclimates (for example distance from the ocean, high wind zones, and salt-fog prone regions) are examined in conjunction… more

Date: March 24, 1996

Creator: Holcomb, G. R.; Covino, B. S., Jr.; Bullard, S. J. & Cramer, S. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Oxidation of alloys targeted for advanced steam turbines

Ultra supercritical (USC) power plants offer the promise of higher efficiencies and lower emissions. Current goals of the U.S. Department of Energy’s Advanced Power Systems Initiatives include coal generation at 60% efficiency, which would require steam temperatures of up to 760°C. This research examines the steamside oxidation of alloys for use in USC systems, with emphasis placed on applications in high- and intermediate-pressure turbines.

Date: March 12, 2006

Creator: Holcomb, G. R.; Covino, B. S., Jr.; Bullard, S. J.; Ziomek-Moroz, M. & Alman, D. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Fireside corrosion probes--an update

The ability to monitor the corrosion degradation of key metallic components in fossil fuel power plants will become increasingly important for FutureGen and ultra-supercritical power plants. A number of factors (ash deposition, coal composition changes, thermal gradients, and low NOx conditions, among others) which occur in the high temperature sections of energy production facilities, will contribute to fireside corrosion. Several years of research have shown that high temperature corrosion ra… more

Date: January 1, 2007

Creator: Covino, B. S., Jr.; Bullard, S. J.; Holcomb, G. R.; Ziomek-Moroz, M. & Matthes, S. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Fireside corrosion probes for fossil fuel combustion

Electrochemical corrosion rate probes have been constructed and tested along with mass loss coupons in environments consisting of N2/O2/CO2/SO2 plus water vapor. Temperatures ranged from 450° to 700°C. Results show that electrochemical corrosion rates for ash-covered mild steel are a function of time, temperature, and gaseous environment. Correlation between the electrochemical and mass loss corrosion rates was poor.

Date: March 1, 2006

Creator: Covino, B. S., Jr.; Bullard, S. J.; Ziomek-Moroz, M.; Holcomb, G. R. & Eden, D. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Studies of Scale Formation and Kinetics of Crofer 22 APU and Haynes 230 in Carbon Oxide-Containing Environment for SOFC Applications

Significant progress in reducing the operating temperature of SOFCs below 800oC may allow the use of chromia-forming metallic interconnects at a substantial cost savings. Hydrogen is the main fuel for all types of fuel cells except direct methanol fuel cells. Hydrogen can be generated from fossil fuels, including coal, natural gas, diesel, gasoline, other hydrocarbons, and oxygenates (e.g., methanol, ethanol, butanol, etc.). Carbon oxides present in the hydrogen fuel can cause significant perfo… more

Date: January 1, 2006

Creator: Ziomek-Moroz, M.; Covino, B. S., Jr.; Holcomb, G. R.; Bullard, S. J. & Penner, L. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Determining the Cause of a Header Failure in a Natural Gas Production Facility

An investigation was made into the premature failure of a gas-header at the Rocky Mountain Oilfield Testing Center (RMOTC) natural gas production facility. A wide variety of possible failure mechanisms were considered: design of the header, deviation from normal pipe alloy composition, physical orientation of the header, gas composition and flow rate, type of corrosion, protectiveness of the interior oxide film, time of wetness, and erosion-corrosion. The failed header was examined using metall… more

Date: March 1, 2007

Creator: Matthes, S. A.; Covino, B. S., Jr.; Bullard, S. J.; Ziomek-Moroz, M. & Holcomb, G. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Atmospheric Corrosion and Precipitation Runoff From Zinc and Zinc Alloys Surfaces

The long-term atmospheric corrosion performance of rolled zinc and three thermal-sprayed (TS) zinc materials (Zn, Zn-15Al, and Al-12Zn-0.2In) was characterized by measuring corrosion product concentrations in precipitation runoff at coastal marine and inland sites. Corrosion rates and average zinc concentrations in the runoff were greater at the site having higher annual rainfall. Higher chloride concentrations did not seem to affect either the corrosion rates or the zinc concentrations in the … more

Date: March 16, 2003

Creator: Matthes, S. A.; Cramer, S. D.; Bullard, S. J.; Covino, B. S., Jr. & Holcomb, G. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Corrosion Performance of Ferritic Steel for SOFC Interconnect Applications

Ferritic stainless steels have been identified as potential candidates for interconnects in planar-type solid oxide fuel cells (SOFC) operating below 800ºC. Crofer 22 APU was selected for this study. It was studied under simulated SOFC-interconnect dual environment conditions with humidified air on one side of the sample and humidified hydrogen on the other side at 750ºC. The surfaces of the oxidized samples were studied by scanning electron microscopy (SEM) equipped with microanalytical capabi… more

Date: November 1, 2006

Creator: Ziomek-Moroz, M.; Holcomb, G. R.; Covino, B. S., Jr.; Bullard, S. J.; Jablonski, P. D. & Alman, D. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ultra-Supercritical Steam Corrosion

Efficiency increases in fossil energy boilers and steam turbines are being achieved by increasing the temperature and pressure at the turbine inlets well beyond the critical point of water. To allow these increases, advanced materials are needed that are able to withstand the higher temperatures and pressures in terms of strength, creep, and oxidation resistance. As part of a larger collaborative effort, the Albany Research Center (ARC) is examining the steam-side oxidation behavior for ultrasu… more

Date: April 22, 2003

Creator: Holcomb, G. R.; Alman, D. E.; Bullard, S. B.; Covino, B. S., Jr.; Cramer, S. D. & Ziomek-Moroz, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Task 2: Boiler Corrosion,

For continued use of coal for power generation, there are needs to: –Improve efficiency –Decrease emissions (esp. CO2) –Use alternate fuels or fuel mixes

Date: April 1, 2009

Creator: Holcomb, G. R.; Covino, B. S., Jr.; Shim, H.-S.; Davis, K.; Eden, D. A.; White, M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Electrochemical Aging of Thermal-Sprayed Zinc Anodes on Concrete

Thermal-sprayed zinc anodes are used in impressed current cathodic protection systems for some of Oregon's coastal reinforced concrete bridges. Electrochemical aging of zinc anodes results in physical and chemical changes at the zinc-concrete interface. Concrete surfaces heated prior to thermal-spraying had initial adhesion strengths 80 pct higher than unheated surfaces. For electrochemical aging greater than 200 kC/m{sup 2} (5.2 A h/ft{sup 2}), there was no difference in adhesion strengths for… more

Date: October 1996

Creator: Holcomb, G. R.; Bullard, S. J.; Covino, B. S., Jr.; Cramer, S. D.; Cryer, C. B. & McGill, G. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Role of Ash Deposits in the High Temperature Corrosion of Boiler Tubes

Ash deposits cause accelerated corrosion of waterwall boiler tubes in waste to energy (WTE) incinerators. To study this effect, a series of experiments were planned to determine the mechanism of corrosion of carbon steel boiler tubes under ash deposits. Results reported here were for carbon steel tubes exposed to an environment consisting of O{sub 2}, CO{sub 2}, N{sub 2}, and water vapor. Future experiments will include HCl and SO{sub 2}. Test procedures included both isothermal and thermal gra… more

Date: March 16, 2003

Creator: Covino, B. S., Jr.; Russell, J. H.; Cramer, S. D.; Holcomb, G. R.; Bullard, S. J.; Ziomek-Moroz, M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Laboratory Evaluation of an Electrochemical Noise System for Detection of Localized and General Corrosion of Natural Gas Transmission Pipelines

Gas transmission pipelines are susceptible to both internal (gas side) and external (soil side) corrosion attack. Internal corrosion is caused by the presence of salt laden moisture, CO{sub 2}, H{sub 2}S, and perhaps O{sub 2} in the natural gas. Internal corrosion usually manifests itself as general corrosion. However, the presence of chlorides in entrained water also can lead to pitting corrosion damage. The electrochemical noise technique can differentiate general from localized corrosion and… more

Date: March 16, 2003

Creator: Bullard, S. J.; Covino, B. S., Jr.; Russell, J. H.; Holcomb, G. R.; Cramer, S. D.; Ziomek-Moroz, M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department