Modeling degradation and failure of Ni-Cr-Al overlay coatings

Nesbitt, James A.; Heckel, R. W.

doi:10.1016/0040-6090(84)90012-9

Cited by 46 publications

(16 citation statements)

References 7 publications

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“…Earlier work on modeling of Al depletion in coatings includes Nesbitt and Heckel [12] who modeled the oxidation of a NiCrAlZr coating on a Ni-base substrate. The model was usable for short thermal exposure but failed to predict Al concentration during the later stages of the coating life.…”

Section: Introductionmentioning

confidence: 99%

“…Overlay coatings are chosen from the MCrAlY family of alloys where M is either of Ni, Co and Fe, or a combination thereof, Y is added to improve the scale adhesion [4,7] while other beneficial minor elements are also added such as Si, Ta, Hf and Zr [3,4,7,12]. The microstructure of MCrAlY coatings includes, most prominently, the γ-, γ'-and β-phases, the former being solid-solution-Ni and the latter two aluminides, Ni 3 Al and NiAl respectively [5,13,14].…”

Section: Introductionmentioning

confidence: 99%

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Modeling of microstructural evolution and lifetime prediction of MCrAlY coatings on nickel based superalloys during high temperature oxidation

Yuan

Eriksson

Peng

et al. 2013

Surface and Coatings Technology

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MCrAlY coatings are deposited onto superalloys to provide oxidation and corrosion protection at high temperature by the formation of a thermally grown oxide scale. In this project, the oxidation behaviour of a HVOF CoNiCrAlYSi coating on IN792 was studied for both isothermal oxidation (900, 1000 and 1100 °C) and thermal cycling (100-1100 °C). The microstructural evolution of the CoNiCrAlYSi coatings after oxidation was investigated. It was found that the Al-rich β phase is gradually consumed due to two effects: surface oxidation and coating-substrate interdiffusion. Some voids and oxides along the coating-substrate interface, or inside the coating, were considered to play a role in blocking the diffusion of alloying elements. Based on the microstructural observation, an oxidation-diffusion model, considering both surface oxidation and coating-substrate interdiffusion, was developed by using Matlab and DICTRA software to predict the useful life of MCrAlY coatings.A new concept of diffusion blocking is also introduced into the model to give more accurate description on the microstructural evolution. The results from modeling and the experimentally established composition profiles showed good agreement.

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Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Modeling of microstructural evolution and lifetime prediction of MCrAlY coatings on nickel based superalloys during high temperature oxidation

Yuan

Eriksson

Peng

et al. 2013

Surface and Coatings Technology

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“…(10), and the proportion of the oxide scale which spalls at each cycle is calculated with Eq. (9). The results are shown in Fig.…”

Section: E-06mentioning

confidence: 63%

“…The relation between spalling and the nature of the oxide scale and its thickness can be studied, and the spalling events can also be detected. Finally, the rate of consumption of the alloying element from the matrix can be calculated as a function of the number of cycles, allowing performance evaluation and timeof-life prediction using a simple reservoir model [8], or as an input for more complex diffusion models for cyclic oxidation [9][10][11] which take into account the concentration gradients in the substrate.…”

Section: Introductionmentioning

confidence: 99%

Cyclic oxidation of coated and uncoated single-crystal nickel-based superalloy MC2 analyzed by continuous thermogravimetry analysis

et al. 2006

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OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible. ] method is applied to the cyclic oxidation at 1150°C of a NiCoCrAlYTa-coated and an uncoated single-crystal nickel-based superalloy MC2. A new procedure to correct the buoyancy effect is proposed in order to evaluate the amount of oxide formed during the heating periods, which can be important for alloys forming fast-growing transient oxides or during cycling with slow heating rates. It is shown that cyclic thermogravimetry is an useful technique for quantifying the oxidation resistance of an industrial alloy. Moreover, the behaviour of the alloy is better described with CTGA than with a classic cyclic gravimetric test, because both isothermal oxidation kinetics and spalling behaviour are assessed independently. In the present case, it is shown clearly that the NiCoCrAlYTa coating greatly improves the cyclic oxidation resistance without decreasing the isothermal oxidation kinetics. Finally, the use of CTGA for performance and time-of-life evaluations is demonstrated.

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“…For example, Pint et al [36] used 10hr thermal cycles in order to simulate the CSP duty cycle for a heat exchanger application at a high temperature, and to force rapid Al depletion for purposes of lifetime prediction. Nesbitt [37] also used cyclic oxidation of 1hr cycles and with a 20min cooling period to assist development of a numerical model (COSIM) to simulate coating degradation by simultaneous oxidation and coating-substrate interdiffusion, namely by measuring the initial Al and Cr contents of the coating and substrate and their concentration -depth profiles.…”

Section: Carburization and Metal Dustingmentioning

confidence: 99%

Corrosion in Supercritical carbon Dioxide: Materials, Environmental Purity, Surface Treatments, and Flow Issues

Sridharan¹,

Anderson²

2013

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Executive SummaryThe supercritical CO 2 Brayton cycle is gaining importance for power conversion in the Generation IV Fast Reactor system because of its high power conversion efficiencies. When used in conjunction with a Sodium Fast Reactor for example, the supercritical CO 2 cycle offers additional safety advantages, by eliminating potential sodium-water interactions that may occur in a steam cycle. In power conversion systems for Generation IV Fast Reactors, supercritical CO 2 temperatures could be in the range of 30oC to 650oC or higher, depending on the specific component in the system. Materials corrosion particularly at the higher temperatures will be an important issue. Therefore, the corrosion performance limits for materials at various temperatures in supercritical CO 2 must be established. Additionally, it is also important to gain a fundamental understanding of mechanisms of materials corrosion in this environment that can guide the selection of alloys for supercritical CO 2 Brayton cycle applications and aid the development of models for long-term corrosion prediction.In this project, the corrosion behavior of various candidate alloys was investigated in supercritical CO 2 at temperatures ranging from 450oC to 650oC for exposure durations of up to 1000 hours (in some cases up to 1500 hours). Most tests were performed at a pressure of 20MPa, although select tests were also performed at 8.27MPa to investigate the role of pressure on corrosion. Alloys investigated included ferritic steels NF616 (Grade T92) and HCM12A (Grade T122), and austenitic alloys IN800H, 347 stainless steel, and three grades of AFA alloys (alumina forming austenitics). AFA alloys, that contain small amounts of aluminum to promote alumina surface layer formation, were developed at Oak Ridge National Laboratory (ORNL) for high temperature oxidation resistance. Tests were performed in research grade (very high purity) and industrial grade CO 2 . Three types of surface treatments, namely, deposition of thin films (~500nm) of aluminum and yttrium, and shot peening were also investigated with the goal of enhancing corrosion resistance.Evaluation of corrosion was performed using weight change measurements, scanning electron microscopy in conjunction with energy dispersive spectroscopy (SEM-EDS), x-ray diffraction (XRD), and for select samples by transmission electron microscopy (TEM). These results are discussed in great detail in the report and in technical papers that have been written or being written on this work. In general ferritic steels exhibited the least corrosion resistance and at best suitable for the lower temperature regime of the temperature range investigated. AFA alloys exhibited better corrosion resistance and in general suitable for the intermediate temperature range, although there was a notable difference in the performance of the three AFA alloys tested. 347 stainless steel and alloy 800H were superior to the other alloys tested with alloy 800H exhibiting the best corrosion resistance. All three surface treatments r...

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Modeling degradation and failure of Ni-Cr-Al overlay coatings

Cited by 46 publications

References 7 publications

Modeling of microstructural evolution and lifetime prediction of MCrAlY coatings on nickel based superalloys during high temperature oxidation

Modeling of microstructural evolution and lifetime prediction of MCrAlY coatings on nickel based superalloys during high temperature oxidation

Cyclic oxidation of coated and uncoated single-crystal nickel-based superalloy MC2 analyzed by continuous thermogravimetry analysis

Corrosion in Supercritical carbon Dioxide: Materials, Environmental Purity, Surface Treatments, and Flow Issues

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