Study of plasma induced nanostructure formation and surface morphology changes on tungsten and stainless steel at atmospheric pressure

Kovach, Yao E.; Zhang, Feifei; Gao, Fei; Foster, John E.

doi:10.1116/1.5030887

Title: Study of plasma induced nanostructure formation and surface morphology changes on tungsten and stainless steel at atmospheric pressure

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Abstract

The formation of nanostructures such as “fuzz,” holes, and flakes was observed on tungsten and stainless steel anodes in a 1 atm glow discharge with helium as the feed gas. The structures exhibited morphology similar to the tungsten fuzz growth observed in experiments that simulate wall conditions in fusion reactors, suggesting that similar physics may be present in both scenarios. The anode surface temperature ranged between 1000 and 1300 K with an ion fluence rate of order 10²⁴s^-1 m^-2. In this work, scanning electron microscope and transmission electron microscope were used to characterize the evolution of nanostructure formation as a function of time. Observed nanostructures were found to vary with the morphology of the discharge plasma attachment. The composition of the structures was found to be predominantly the native metal by using energy dispersive x-ray spectroscopy. This work gives some insight into the formation of nanostructures at atmospheric pressure, which not only has applications for material processing, but also provides potentially another avenue to study fuzz formation processes relevant to fusion plasma-wall interactions.

Authors:

Kovach, Yao E. ^[1]; Zhang, Feifei ^[1]; Gao, Fei ^[1]; Foster, John E. ^[1]

Univ. of Michigan, Ann Arbor, MI (United States)

Publication Date:: Fri Dec 07 00:00:00 EST 2018

Research Org.:: Univ. of Michigan, Ann Arbor, MI (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES)

Contributing Org.:: Michigan Memorial Phoenix Project (MMPP)

OSTI Identifier:: 1598472

Grant/Contract Number:: SC0001939

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Vacuum Science and Technology A

Additional Journal Information:: Journal Volume: 37; Journal Issue: 1; Journal ID: ISSN 0734-2101

Publisher:: American Vacuum Society / AIP

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; nanostructure; plasma; tungesten fuzz; fusion

Citation Formats


                    Kovach, Yao E., Zhang, Feifei, Gao, Fei, and Foster, John E. Study of plasma induced nanostructure formation and surface morphology changes on tungsten and stainless steel at atmospheric pressure.  United States: N. p., 2018. 
Web.  doi:10.1116/1.5030887.

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                    Kovach, Yao E., Zhang, Feifei, Gao, Fei, & Foster, John E. Study of plasma induced nanostructure formation and surface morphology changes on tungsten and stainless steel at atmospheric pressure.  United States.  https://doi.org/10.1116/1.5030887

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                    Kovach, Yao E., Zhang, Feifei, Gao, Fei, and Foster, John E. Fri .  
"Study of plasma induced nanostructure formation and surface morphology changes on tungsten and stainless steel at atmospheric pressure".  United States.  https://doi.org/10.1116/1.5030887.  https://www.osti.gov/servlets/purl/1598472.

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@article{osti_1598472,

  title        = {Study of plasma induced nanostructure formation and surface morphology changes on tungsten and stainless steel at atmospheric pressure},

  author       = {Kovach, Yao E. and Zhang, Feifei and Gao, Fei and Foster, John E.},

  abstractNote = {The formation of nanostructures such as “fuzz,” holes, and flakes was observed on tungsten and stainless steel anodes in a 1 atm glow discharge with helium as the feed gas. The structures exhibited morphology similar to the tungsten fuzz growth observed in experiments that simulate wall conditions in fusion reactors, suggesting that similar physics may be present in both scenarios. The anode surface temperature ranged between 1000 and 1300 K with an ion fluence rate of order 1024s-1 m-2. In this work, scanning electron microscope and transmission electron microscope were used to characterize the evolution of nanostructure formation as a function of time. Observed nanostructures were found to vary with the morphology of the discharge plasma attachment. The composition of the structures was found to be predominantly the native metal by using energy dispersive x-ray spectroscopy. This work gives some insight into the formation of nanostructures at atmospheric pressure, which not only has applications for material processing, but also provides potentially another avenue to study fuzz formation processes relevant to fusion plasma-wall interactions.},

  doi          = {10.1116/1.5030887},

  journal      = {Journal of Vacuum Science and Technology A},

  number       = 1,

  volume       = 37,

  place        = {United States},

  year         = {Fri Dec 07 00:00:00 EST 2018},

  month        = {Fri Dec 07 00:00:00 EST 2018}

}

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