Effect of Ga on the Oxide Film Structure and Oxidation Resistance of Sn–Bi–Zn Alloys as Heat Transfer Fluids

The effect of gallium on the oxide film structure and overall oxidation resistance of low melting point Sn–Bi–Zn alloys was investigated under air atmosphere using thermogravimetric analyses. The liquid alloys studied had a Ga content of 1–7 wt.%. The results showed that the growth rates of the surface scale formed on the Sn–Bi–Zn–Ga alloys conformed to the parabolic law. The oxidation resistance of Sn–Bi–Zn alloys was improved by Ga addition and the activation energies increased from 12.05 kJ∙mol−1 to 22.20 kJ∙mol−1. The structure and elemental distribution of the oxide film surface and cross-section were found to become more complicated and denser with Ga addition. Further, the results of X-ray photoelectron spectroscopy and X-ray diffraction show that Ga elements accumulate on the surface of the liquid metal to form oxides, which significantly slowed the oxidation of the surface of the liquid alloy.

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Surface Stoichiometry and Depth Profile of Tix-CuyNz Thin Films Deposited by Magnetron Sputtering

Materials ◽

10.3390/ma14123191 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3191

Author(s):

Arun Kumar Mukhopadhyay ◽

Avishek Roy ◽

Gourab Bhattacharjee ◽

Sadhan Chandra Das ◽

Abhijit Majumdar ◽

...

Keyword(s):

Magnetron Sputtering ◽

Photoelectron Spectroscopy ◽

Film Surface ◽

Grazing Incidence ◽

X Ray Diffraction ◽

X Ray ◽

Relative Composition ◽

Transmission Electron ◽

Deposited Film ◽

Deposited Films

We report the surface stoichiometry of Tix-CuyNz thin film as a function of film depth. Films are deposited by high power impulse (HiPIMS) and DC magnetron sputtering (DCMS). The composition of Ti, Cu, and N in the deposited film is investigated by X-ray photoelectron spectroscopy (XPS). At a larger depth, the relative composition of Cu and Ti in the film is increased compared to the surface. The amount of adventitious carbon which is present on the film surface strongly decreases with film depth. Deposited films also contain a significant amount of oxygen whose origin is not fully clear. Grazing incidence X-ray diffraction (GIXD) shows a Cu3N phase on the surface, while transmission electron microscopy (TEM) indicates a polycrystalline structure and the presence of a Ti3CuN phase.

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GROWTH OF OXIDE LAYER ON GERMANIUM (011) SUBSTRATE UNDER DRY AND WET ATMOSPHERES

Surface Review and Letters ◽

10.1142/s0218625x99001141 ◽

1999 ◽

Vol 06 (06) ◽

pp. 1053-1060 ◽

Cited By ~ 11

Author(s):

N. TABET ◽

J. AL-SADAH ◽

M. SALIM

Keyword(s):

Simple Model ◽

Oxide Film ◽

Growth Kinetics ◽

Photoelectron Spectroscopy ◽

Early Stage ◽

X Ray ◽

Apparent Thickness ◽

Different Temperatures ◽

Kinetics Of

X-ray Photoelectron Spectroscopy (XPS) has been used to investigate the oxidation of (011) Ge substrates. The sample surfaces were CP4-etched, then annealed in situ, at different temperatures, for various durations. Dry and wet atmospheres were used. The oxidation rate during the early stage was increased by the presence of moisture in the atmosphere. A simple model was used to define and determine an apparent thickness of the oxide film from XPS measurements. The time dependence of the apparent thickness is consistent with a partial coverage of the surface by oxide islands. The growth kinetics of the oxide islands obeys a nearly cubic law.

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Characterization of native oxide film on amorphous Co66Si16B12Fe4Mo2 by X-ray photoelectron spectroscopy

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2009.10.119 ◽

2010 ◽

Vol 490 (1-2) ◽

pp. 613-617 ◽

Cited By ~ 1

Author(s):

Rohit Jain ◽

Deepika Bhandari ◽

Anil Dhawan ◽

S.K. Sharma

Keyword(s):

Oxide Film ◽

Photoelectron Spectroscopy ◽

Native Oxide ◽

X Ray

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The piezoresistive properties research of SiC thin films prepared by RF magnetron sputtering

International Journal of Modern Physics B ◽

10.1142/s0217979219501522 ◽

2019 ◽

Vol 33 (15) ◽

pp. 1950152 ◽

Cited By ~ 1

Author(s):

Jing Wu ◽

Xiaofeng Zhao ◽

Chunpeng Ai ◽

Zhipeng Yu ◽

Dianzhong Wen

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Cantilever Beam ◽

Photoelectron Spectroscopy ◽

Film Surface ◽

Rf Magnetron Sputtering ◽

Micro Electro Mechanical System ◽

Gauge Factor ◽

X Ray ◽

Sputtering Power

To research the piezoresistive properties of SiC thin films, a testing structure consisting of a cantilever beam, SiC thin films piezoresistors and a Cr/Pt electrode is proposed in this paper. The chips of testing structure were fabricated by micro-electro-mechanical system (MEMS) technology on a silicon wafer with [Formula: see text]100[Formula: see text] orientation, in which SiC thin films were deposited by using radio-frequency (13.56 MHz) magnetron sputtering method. The effect of sputtering power, annealing temperature and time on the microstructure and morphology of the SiC thin films were investigated by the X-ray diffraction (XRD) and scanning electron microscopy (SEM). It indicates that a good continuity and uniform particles on the SiC thin film surface can be achieved at sputtering power of 160 W after annealing. To verify the existence of Si–C bonds in the thin films, X-ray photoelectron spectroscopy (XPS) was used. Meanwhile, the piezoresistive properties of SiC thin films piezoresistors were measured using the proposed cantilever beam. The test result shows that it is possible to achieve a gauge factor of 35.1.

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Vacuum tribological properties of a composite Mo–MoS2film after atomic oxygen exposure irradiation

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650119827427 ◽

2019 ◽

Vol 233 (8) ◽

pp. 1236-1244

Author(s):

Guo-zheng Ma ◽

Peng-fei He ◽

Yi-wen Wang ◽

Shu-ying Chen ◽

Ming Liu ◽

...

Keyword(s):

Tribological Properties ◽

Photoelectron Spectroscopy ◽

Atomic Oxygen ◽

Sliding Friction ◽

Film Surface ◽

Superficial Layer ◽

Solid Lubrication ◽

X Ray ◽

Nanomechanical Properties ◽

Lubrication Film

A composite Mo–MoS2solid-lubrication film measuring approximately 2-µm thick was prepared using a two-step composite process involving magnetron sputtering of Mo film followed by low-temperature ion sulfurization. Microstructure of the said film was characterized using scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Auger electron spectroscopy, and X-ray photoelectron spectroscopy, and nanomechanical properties of the Mo and Mo–MoS2film were tested using a nanoindenter. The Mo–MoS2film and GCr15 substrate were irradiated by atomic oxygen with the self-developed MSTS-1 space tribometer system equipped with an atomic oxygen beam at a flux of 9 × 1019atoms/cm2. Subsequently, vacuum tribological properties of the said substrate and film were examined and compared. Results demonstrated that the Mo film possessed a smooth and dense structure with stable nanomechanical properties. Part of the elemental Mo translated into MoS2post sulfurizing, thereby forming the Mo–MoS2composite film with an alternating soft and hard structure. The Mo–MoS2film demonstrated a low and stable friction coefficient of approximately 0.15 along with only a slight wear in vacuum. The film surface could be oxidized and eroded when exposed to the highly active and energetic atomic oxygen. Post atomic oxygen erosion, the film thickness demonstrated a decrease, and small amounts of MoO3were observed on the surface. However, all structural and property changes were limited to the superficial layer. The excellent tribological performance of the film could be restored when the surface layer was removed after a certain period of sliding friction.

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Preparation and characterization of polyphenylene sulfide/graphene nanoplatelets composite fibers with enhanced oxidation resistance

High Performance Polymers ◽

10.1177/0954008319867748 ◽

2019 ◽

Vol 32 (4) ◽

pp. 394-405 ◽

Cited By ~ 1

Author(s):

Jian Xing ◽

Zhenzhen Xu ◽

Qing-Qing Ni ◽

Huizhen Ke

Keyword(s):

Oxidation Resistance ◽

Photoelectron Spectroscopy ◽

Melt Spinning ◽

Retention Rate ◽

Graphene Nanoplatelets ◽

Polyphenylene Sulfide ◽

Degree Of Crystallinity ◽

Composite Fibers ◽

Oxidation Treatment ◽

X Ray

Composite masterbatches of polyphenylene sulfide (PPS) with functionalized graphene nanoplatelets (GNPs) were prepared by melt blending via a twin-screw extruder. The structure and morphology of composite masterbatches were characterized by scanning electron microscopy and X-ray diffraction analysis. The PPS/functionalized GNPs composite fibers were then manufactured by a self-made spinning equipment via melt spinning. The oxidation resistance and other properties of PPS composite fibers were also examined. The results showed that the pure PPS fibers exhibited smooth surface, whereas the surface of PPS/functionalized GNPs composite fibers was rough. The addition of functionalized GNPs could be acted as heterogeneous nucleating agents to improve the crystallization and increase the degree of crystallinity. The retention rate of breaking strength of PPS/functionalized GNPs composite fibers could maintain up to 85% after the oxidation treatment. The improvement in the oxidation resistance of PPS/functionalized GNPs composite fibers is the results of comprehensive effects characterized by the X-ray photoelectron spectroscopy analyses. The addition of functionalized GNPs could limit the damage of the C–S group and retard the generation of sulfuryl groups (–SO–) during the oxidation treatment. The chemical combination of the elements sulfur (S) and oxygen (O) could also be restricted, thus weakening the oxidation activity.

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The Effects of Annealing Temperature on the Structural Properties of ZrB2 Films Deposited via Pulsed DC Magnetron Sputtering

Coatings ◽

10.3390/coatings9040253 ◽

2019 ◽

Vol 9 (4) ◽

pp. 253 ◽

Cited By ~ 2

Author(s):

Wei-Chun Chen ◽

Chao-Te Lee ◽

James Su ◽

Hung-Pin Chen

Keyword(s):

Electron Microscopy ◽

Magnetron Sputtering ◽

Structural Properties ◽

Photoelectron Spectroscopy ◽

Annealing Temperature ◽

High Vacuum ◽

Film Structure ◽

Dc Magnetron Sputtering ◽

Cross Sectional ◽

X Ray

Zirconium diboride (ZrB2) thin films were deposited on a Si(100) substrate using pulsed direct current (dc) magnetron sputtering and then annealed in high vacuum. In addition, we discussed the effects of the vacuum annealing temperature in the range of 750 to 870 °C with flowing N2 on the physical properties of ZrB2 films. The structural properties of ZrB2 films were investigated with X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The XRD patterns indicated that the ZrB2 films annealed at various temperatures exhibited a highly preferred orientation along the [0001] direction and that the residual stress could be relaxed by increasing the annealing temperature at 870 °C in a vacuum. The surface morphology was smooth, and the surface roughness slightly decreased with increasing annealing temperature. Cross-sectional TEM images of the ZrB2/Si(100) film annealed at 870 °C reveals the films were highly oriented in the direction of the c-axis of the Si substrate and the film structure was nearly stoichiometric in composition. The XPS results show the film surfaces slightly contain oxygen, which corresponds to the binding energy of Zr–O. Therefore, the obtained ZrB2 film seems to be quite suitable as a buffer layer for III-nitride growth.

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