Development of model predictive control of fluorine density in SF6/O2/Ar etch plasma by oxygen flow rate

ABSTRACTFormation of ferrites from aqueous solution of metal salts is a well known process involving precipitation of metal hydroxides followed by oxidation of the resulting gel. The purpose of the present work was to determine the effects oxygen flow rate on the progress of the reaction and on the structure and properties of the resulting precipitate. The reaction was carried out at 70°C with pH of 10.5 and oxygen flow rate of 2,4, or 8 standard liters per hour. The progress of the reaction was monitored by following the oxidation-reduction potential of the solution, which changes dramatically after the Fe(II) is consumed. The reaction rate increased with increasing oxygen flow rate. The Mg content of the precipitate was lower than that of the reaction mixture, possibly because of the pH of the reaction mixture. X-ray diffraction and infrared spectroscopy confirmed formation of a ferrite under these conditions.

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Novel Liquid Fuel HVOF Torches Fueled with Ethanol: Optimization and Erosion Wear Response of Cr3C2-NiCr Coatings

Thermal Spray 2021: Proceedings from the International Thermal Spray Conference ◽

10.31399/asm.cp.itsc2021p0079 ◽

2021 ◽

Author(s):

Shaowu Liu ◽

Michel Moliere ◽

Hanlin Liao

Keyword(s):

Flow Rate ◽

Feed Rate ◽

Impact Angle ◽

Oxygen Flow Rate ◽

Oxygen Flow ◽

Standoff Distance ◽

Wear Loss ◽

Erosion Wear ◽

Powder Feed Rate ◽

Powder Feed

Abstract In this work; a novel liquid fuel HVOF process fueled with ethanol was used to prepare 75wt%Cr3C2–25wt%NiCr coatings on AISI304 stainless steel substrate. Taguchi method was employed to optimize the spray parameters (ethanol flow rate; oxygen flow rate; powder feed rate and standoff distance) to achieve better erosion resistance at 90° impact angle. The results indicated that ethanol flow rate and oxygen flow rate were identified as the highly contributing parameters on the erosion wear loss. The important sequence of the spray parameter is ethanol flow rate > oxygen flow rate > standoff distance > powder feed rate. The optimal spray parameter (OSP) for minimum erosion wear loss was obtained under ethanol flow rate of 28slph; oxygen flow rate of 420slpm; powder feed rate of 76.7 g/min and standoff distance of 300mm. The phase composition; microstructure; hardness; porosities; and the erosion wear behaviors of the coatings have been studied in detail. Besides; erosion wear testing of the optimized coating was conducted at 30°; 60° and 90° impact angle using air jet erosion testing machine. The SEM images of the erodent samples were taken to analyze the erosion mechanism.

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An Influence of Oxygen Flow Rate on Structural, Optical and Tribological Properties of Molybdenum Oxide Thin Films

Advanced Engineering Forum ◽

10.4028/www.scientific.net/aef.39.43 ◽

2021 ◽

Vol 39 ◽

pp. 43-53

Author(s):

Divyeshkumar P. Dave ◽

Akshay M. Patel ◽

Kamlesh V. Chauhan ◽

Sushant K. Rawal

Keyword(s):

Wear Rate ◽

Molybdenum Oxide ◽

Tribological Properties ◽

Flow Rate ◽

Gas Flow ◽

Visible Region ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Oxygen Flow Rate ◽

Oxygen Flow

The influence of oxygen flow rate is examined on structural, optical and tribological properties of molybdenum oxide films deposited by reactive magnetron sputtering. The films were characterized by X-ray diffraction, scanning electron microscope (SEM), and contact angle measurement system. The optical properties of the films were measured by UV-Vis-NIR spectrophotometer and transmittance of ∼73% in the visible region of the spectrum was achieved. The band gap increases with increases in oxygen gas flow rate. AFM figure illustrates that the roughness of surface increases as oxygen flow rate increases. As oxygen increases wear rate and COF decreases while at the 18 sccm the lowest wear rate found.

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Role of oxygen flow rate on the structure and stoichiometry of cobalt oxide films deposited by reactive sputtering

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films ◽

10.1116/6.0001418 ◽

2022 ◽

Vol 40 (1) ◽

pp. 013405

Author(s):

Nilton Francelosi A. Neto ◽

Cristiane Stegemann ◽

Lucas J. Affonço ◽

Douglas M. G. Leite ◽

José H. D. da Silva

Keyword(s):

Cobalt Oxide ◽

Flow Rate ◽

Oxide Films ◽

Reactive Sputtering ◽

Oxygen Flow Rate ◽

Oxygen Flow

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Relationship between Oxygen Defects and Properties of Scandium Oxide Films Prepared by Ion-Beam Sputtering

Coatings ◽

10.3390/coatings9080517 ◽

2019 ◽

Vol 9 (8) ◽

pp. 517

Author(s):

Pengfei Kong ◽

Yunti Pu ◽

Ping Ma ◽

Jiliang Zhu

Keyword(s):

Refractive Index ◽

Surface Quality ◽

Flow Rate ◽

Ion Beam ◽

Oxygen Flow Rate ◽

Scandium Oxide ◽

Oxygen Flow ◽

Ion Beam Sputtering ◽

Oxygen Defects ◽

Beam Sputtering

Scandium oxide (Sc2O3) thin films with different numbers of oxygen defects were prepared by ion-beam sputtering under different oxygen flow rates. The results showed that the oxygen defects heavily affected crystal phases, optical properties, laser-induced damage threshold (LIDT) and surface quality of Sc2O3 films. The thin film under 0 standard-state cubic centimeter per minute (sccm) oxygen flow rate had the largest number of oxygen defects, which resulted in the lowest transmittance, LIDT and the worst surface quality. In addition, the refractive index of 0 sccm Sc2O3 film could not be measured in the same way. When the oxygen flow rate was 15 sccm, the Sc2O3 film possessed the best transmittance, refractive index, LIDT and surface roughness due to the lowest number of oxygen defects. This work elucidated the relationship between oxygen defects and properties of Sc2O3 films. Controlling oxygen flow rate was an important step of limiting the number of oxygen defects, which is of great significance for industrial production.

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Spectroscopic Studies of Magnetron Sputtering Plasma Discharge in Cu/O2/Ar Mixture for Copper Oxide Thin Film Fabrication

Jurnal Teknologi ◽

10.11113/jt.v73.2984 ◽

2015 ◽

Vol 73 (1) ◽

Cited By ~ 1

Author(s):

Jia Wei Low ◽

Nafarizal Nayan ◽

Mohd Zainizan Sahdan ◽

Mohd Khairul Ahmad ◽

Ali Yeon Md Shakaff ◽

...

Keyword(s):

Thin Film ◽

Copper Oxide ◽

Flow Rate ◽

Langmuir Probe ◽

Oxygen Flow Rate ◽

Oxygen Flow ◽

Oxide Thin Film ◽

Substrate Bias ◽

Substrate Bias Voltage ◽

Copper Oxide Thin Film

Magnetron sputtering plasma for the deposition of copper oxide thin film has been investigated using optical emission spectroscopy and Langmuir probe. The intensity of the light emission from atoms and radicals in the plasma were measured using optical emission spectroscopy (OES). Then, Langmuir probe was employed to estimate the plasma density, electron temperature and ion flux. In present studies, reactive copper sputtering plasmas were produced at different oxygen flow rate of 0, 4, 8 and 16 sccm. The size of copper target was 3 inches. The dissipation rf power, Ar flow rate and working pressure were fixed at 400 W, 50 sccm and 22.5 mTorr, respectively. Since the substrate bias plays an important role to the thin film formation, the substrate bias voltages of 0, -40, -60 and -100 V were studied. Based on OES results, oxygen emission increased drastically when the oxygen flow rate above 8 sccm. On the other hand, copper and argon emission decreased gradually. In addition, Langmuir probe results showed a different ion flux when substrate bias voltage was applied. Based on these plasma diagnostic results, it has been concluded that the optimized parameter to produce copper oxide thin film are between -40 to -60 V of substrate bias voltage and between 8 to 12 sccm of oxygen flow rate.

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The Oxygen Delivery Characteristics of the Hudson Oxy-one Face Mask

Anaesthesia and Intensive Care ◽

10.1177/0310057x8901700210 ◽

1989 ◽

Vol 17 (2) ◽

pp. 180-184 ◽

Cited By ~ 10

Author(s):

J. Milross ◽

I. H. Young ◽

P. Donnelly

Keyword(s):

Flow Rate ◽

Oxygen Delivery ◽

Face Mask ◽

Oxygen Flow Rate ◽

Oxygen Flow ◽

Face Model ◽

Oxygen Fraction ◽

Constant Rate ◽

The Face ◽

Definition Of

The inspired oxygen fraction (FIO2) delivered by the Hudson Oxy-one face mask was measured under changing conditions of ventilation, oxygen flow rate to mask, and mask fit. A single trained subject sat in a body plethysmograph to measure ventilation and breathed at a constant rate of 15 per minute at three different tidal volumes, of approximately 0.3, 0.6, and 1.2 litres, from the mouthpiece in the plethysmograph. The Oxy-one face mask was fitted to a plaster-of Paris face model on the outside of the plethysmograph in a loose and then in a tight fashion. Oxygen concentration was continuously monitored from a point in the metal tube connecting the face model to the mouthpiece. The tightly fitting mask demonstrated an orderly reduction in FIO2 as ventilation increased and oxygen flow rate to the mask decreased. The mean FIO2 at a ventilation of 4.5 l.min-1 and 8 l.min-1 oxygen flow was 78% and this fell to 27% at a ventilation of 16 l.min-1 and oxygen flow of 2 l.min-1. The loosely fitting mask demonstrated larger SD of measurements and lower mean maximum FIO2 values of 46 to 49% and these fell in an irregular fashion to similar minimum values as ventilation increased and oxygen flow decreased. Although the precise definition of the FIO2 for each breath from the changing concentration during each inspiration was not possible, these results indicate that FIO2 changes in a predictable way as a function of ventilation and oxygen flow, if the mask is close fitting. This method could be conveniently used to study other oxygen delivery systems.

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