Publications

Nov, 2023

ORNL Report

Development of an Open-source Alloy selection and Lifetime assessment tool for structural components in CSP

Nov, 2023

Journal

Oxidation Lifetime Modeling of 625 and 120 Foils After Long-term Exposure in Flowing Air + 10% H2O at 700 and 800 ∘C

A model describing oxidation kinetics considering simultaneous oxidation and volatilization of external oxide scales was integrated with a CALPHAD-based coupled thermodynamic and kinetic approach to predict the oxidation-induced lifetime of foils of alloys 625 and 120. Long-term exposures in flowing air +10% H2O at 700 and 800 ∘C under two flow velocities were used to vali…

Nov, 2023

Journal

Measuring oxygen solubility in Ni grains and boundaries after oxidation using atom probe tomography

Poor oxidation resistance is a key contributor to material failure within extreme environments. Understanding oxygen solubility is important for computation aided design of new high strength, high-temperature oxidation resistant alloys. Oxygen solubility within pure metals, such as Ni, has been studied using a multitude of techniques, but Atom Probe Tomography (APT) has no…

Nov, 2023

Conference Paper

Compatibility Of Steels At 450°-650°C In Supercritical CO2 With O2 And H2O Additions

Direct-fired supercritical CO2 (sCO2) power cycles are being commercialized to revolutionize fossil energy as a low-emission power source. However, the cycle will increase O2 and H2O in the sCO2 and the implications of these additions have not been fully studied, particularly for lower cost steels that are needed in the lower temperature segments of the plant. Representati…

Nov, 2023

Journal

Compatibility of Fe-Cr-Al and Fe-Cr-Al-Mo oxide dispersion strengthened steels with static liquid sodium at 700 ° C

The corrosion behavior and tensile properties of oxide dispersion strengthened (ODS) FeCr, FeCrAl, FeCrAlMo steels and 316H stainless steel were evaluated after 1000 h at 700 C in static sodium with and without an oxygen getter (Zr foil). Without Zr foil to getter the dissolved oxygen in the liquid sodium, combined oxidation (formation of Cr, Fe-rich or Al-rich oxides) and…

Aug, 2023

Conference Paper

LEVERAGING ADDITIVE MANUFACTURING TO FABRICATE HIGH TEMPERATURE ALLOYS WITH CO-DESIGNED MECHANICAL PROPERTIES AND ENVIRONMENTAL RESISTANCE

Aug, 2022

Journal

Comparison of Na2SO4, K2SO4 and Na2SO4-K2SO4 deposit induced hot corrosion of a β-NiAl coating

Hot corrosion behaviour of a β-NiAl coating induced by Na2SO4, K2SO4, and Na2SO4-K2SO4 deposits was investigated at 700 °C in air + 300 ppm SO2. To provide an insight into the corrosion mechanisms, phase equilibria of the Na2SO4-K2SO4-NiO-SO3 system were calculated using an in-house developed thermodynamic database. The attack rates and morphologies could be correlated wit…

Aug, 2019

Journal

Microstructural evolution of an aluminide coating on alloy 625 during wet air exposure at 900 °C and 1000 °C

The microstructural changes of the aluminized alloy 625 during cyclic oxidation in air + 6% H2O at 900 °C and 1000 °C were analyzed using optical metallography (OM), scanning electron microscopy (SEM) with energy and wave length dispersive X-ray analysis (EDX/WDX) as well as electron backscatter diffraction (EBSD). An in-house developed thermodynamic-kinetic procedure was…

Jul, 2019

Journal

Simulating the effect of aluminizing on a CoNiCrAlY-coated Ni-base superalloy

MCrAlY (M = Ni, Co) coatings are commonly used on gas-turbine components as oxidation resistant overlay coatings and bondcoats for thermal barrier systems. The present work focuses on the effect of the aluminizing process on the CoNiCrAlY coating microstructure. In the as-received condition the outer part of the coating consisted mostly of β-(Ni,Co)Al with interspersed pre…