33 Result(s)

Article

Role of Elemental Segregation on the Oxidation Behavior of Additively Manufactured Alloy 625

This study presents the microstructure and oxidation behavior at 800°C in the air of Alloy 625 manufactured by conventional manufacturing and laser-assisted additive manufacturing (AM) processes: powder bed fu...

G. de Leon Nope, G. Wang, J. M. Alvarado-Orozco, B. Gleeson in JOM (2022)

Article

Do Mass Transport Kinetics Always Control Al₂O₃ Scale Growth? An Alternative Explanation for the Efficacy of the Reactive-Element Effect

A. H. Heuer, B. Gleeson in Oxidation of Metals (2020)

Chapter and Conference Paper

Effects of CO₂ Cover Gas and Yttrium Additions on the Oxidation of AlMg Alloys

AlMg alloys are known to suffer from problematic that can result in significant dross formation and loss of Mg from the melt. Historically, beryllium has been used to minimize the as it forms a protective ...

N. Smith, B. Gleeson, W. Saidi, A. Kvithyld, G. Tranell in Light Metals 2019 (2019)

Article

Reinterpretation of Type II Hot Corrosion of Co-Base Alloys Incorporating Synergistic Fluxing

The components of gas-turbine engines operating in marine environments are highly susceptible to hot corrosion, which is typically classified as Type II (650–750 °C) and Type I (900–950 °C) hot-corrosion attac...

J. M. Alvarado-Orozco, J. E. Garcia-Herrera, B. Gleeson… in Oxidation of Metals (2018)

Article

Promotion of the Al₂O₃-Scale Formation on Ni–Cr–Al Alloys via the Fluorine Effect

The halogen effect, which involves the surface enrichment of an alloy with a halogen element to result in improved oxidation resistance, was assessed using model Ni-based Ni–Cr–Al alloys. The alloys studied va...

H.-E. Zschau, W. Zhao, S. Neve, B. Gleeson, M. Schütze in Oxidation of Metals (2015)

Article

Kinetic Study of the Competitive Growth Between θ-Al₂O₃ and α-Al₂O₃ During the Early Stages of Oxidation of β-(Ni,Pt)Al Bond Coat Systems: Effects of Low Oxygen Partial Pressure and Temperature

An oxidation study of β-(Ni,Pt)Al commercial bond coat systems was carried by means of TGA analysis during isothermal treatments at temperatures from 1273 K to 1423 K (1000 °C to 1150 °C). The effect of oxygen pa...

J. M. Alvarado-Orozco, R. Morales-Estrella… in Metallurgical and Materials Transactions A (2015)

Article

Alloying-Element Loss During High-Temperature Processing of a Nickel-Base Superalloy

The effect of exposure at temperatures commonly used for wrought processing/heat treatment of nickel-base superalloys on the loss of alloying elements at the free surface has been determined. For this purpose,...

S. L. Semiatin, J. M. Shank, W. M. Saurber… in Metallurgical and Materials Transactions A (2014)

Article

The Effect of Microstructure on the Type II Hot Corrosion of Ni-Base MCrAlY Alloys

Alloys of compositions (in wt%) Ni–31.5Cr–11.5Al–0.6Y and Ni–20.9Co–19.2Cr–12.5Al–0.5Y–0.4Si–0.3Hf were prepared using three different processing routes and exposed to Type II (700 °C) hot corrosion conditions...

M. N. Task, B. Gleeson, F. S. Pettit, G. H. Meier in Oxidation of Metals (2013)

Article

A combined map** process for the development of platinum-modified Ni-based superalloys

Heat-resistant Ni-based alloys have been used extensively for components in turbine engines for the past 50 years. Platinum group metal (PGM) alloying additions (i.e., platinum and iridium) have been found in ...

A. J. Heidloff, Z. Tang, F. Zhang, B. Gleeson in JOM (2010)

Article

Sulfur Segregation at Al₂O₃/γ-Νi + γ′-Ni₃Al Interfaces: Effects of Pt, Cr and Hf Additions

The interfacial chemistry that developed as a result Al₂O₃-scale growth on γ-Νi + γ′-Ni₃Al alloys at 1150 °C was studied using scanning Auger microscopy after the oxide layer was scratched to spall under ultra-hi...

P. Y. Hou, T. Izumi, B. Gleeson in Oxidation of Metals (2009)

Article

Structural Stability of Platinum-Group-Metal-Modified γ + γ′ Ni-Base Alloys

The structural and surface stabilities of two experimental γ-Ni+γ′-Ni₃Al-base alloys containing Pt or Ir were investigated. These alloys are representative of alloys currently being developed to occupy a unique d...

A. J. Heidloff, J. Van Sluytman… in Metallurgical and Materials Transactions A (2009)

Article

Compositional factors affecting the establishment and maintenance of Al₂O₃ scales on Ni–Al–Pt systems

The beneficial role played by platinum addition in promoting the formation of a protective Al₂O₃ scale on representative γ′-Ni₃Al+γ-Ni coating compositions during high-temperature oxidation is discussed. This ben...

B. Gleeson, N. Mu, S. Hayashi in Journal of Materials Science (2009)

Article

Correlation between the Microstructure, Growth Mechanism, and Growth Kinetics of Alumina Scales on a FeCrAlY Alloy

The microstructural development of an alumina scale formed on a model FeCrAlY alloy during oxidation at 1200 °C was characterized for up to 2000 hours of growth. Quantitative scanning electron microscopy (SEM)...

D. Naumenko, B. Gleeson, E. Wessel… in Metallurgical and Materials Transactions A (2007)

Article

Effects of Silicon on the Oxidation Behavior of Ni-Base Chromia-Forming Alloys

This paper compares and analyzes the oxidation behavior of Ni-base alloys with and without about 2.7 wt.% Si addition. The Ni-base alloys studied were of two types: cast model alloys or wrought commercial allo...

B. Li, B. Gleeson in Oxidation of Metals (2006)

Article

Scaling of Carbon Steel in Simulated Reheat Furnace Atmospheres

A low carbon steel was exposed to a series of laboratory-simulated combustion gases at temperatures of 700--1200°C. The gases corresponded to the products of burning natural gas with amounts of air varying fr...

V. H. J. Lee, B. Gleeson, D. J. Young in Oxidation of Metals (2005)

Article

Effects of Minor Elements on the Cyclic-Oxidation Behavior of Commercial Fe-Base 800-Series Alloys

The cyclic-oxidation behavior of commercial iron-base 800-series chromia-scale-forming alloys was studied at 1000°C in still air. Each thermal cycle consisted of one day at temperature followed by air cooling ...

B. Li, B. Gleeson in Oxidation of Metals (2004)

Article

Modelling gas motion in a rapid-compression machine

In this paper, a model which describes the behaviour of the pressure, density and temperature of a gas mixture in a rapid compression machine is developed and analyzed. The model consists of a coupled system o...

M.G. Meere, B. Gleeson, J.M. Simmie in Journal of Engineering Mathematics (2002)

Article

Rapid Growth of SiO2 Nanofibers on Silicon-Bearing Alloys

Exposure of Ni–Si and Co–Si alloys to Ar–CO₂ and Ar–CO–CO₂ gases at 1130°C led to rapid growth of crystalline SiO₂ nanofibers from the alloy surfaces. The fibers were circular in cross section, of diameter about ...

P. Carter, B. Gleeson, D. J. Young in Oxidation of Metals (2001)

Article

Alloy design strategies for promoting protective oxide-scale formation

This article discusses general strategies for designing alloys to form protective oxide scales. Approaches based on classical alloyoxidation theories work reasonably well for single-phase alloys. However, high...

M. P. Brady, I. G. Wright, B. Gleeson in JOM (2000)