Air-thermal oxidation of zirconium

Zirconium is one of those few metals which are capable of dissolving relativelylarge quantities of oxygen. When heated in air at elevated temperatures, anoxide layer is built up at the metal surface. The oxidation of mechanicallypolished zirconium was studied in the range 500-900oC in air atmosphere, attemperature intervals of 100oC, for exposure times from 5 min to 1860 min foreach temperature. The weight gain of the oxidized species was the reactedamount of oxygen with zirconium for the formation of the ZrO2. The weight gainand thickness of the oxide film increase with the increasing of the oxidation timeand temperature. The oxidation initially followed a parabolic rate at alltemperatures. At temperatures higher than 700oC oxide “breakaway” appears atthe longest oxidation times. Microstructural investigations have shown that theoxide layers are compact and with good adhesion to the metal surface, but attemperatures over 700oC, radial micro-cracks appear. Raman spectra of theformed oxides at the investigated temperatures are characteristic for monoclinicphase.

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Residual Stress Measurement in Silicon Substrate After Local Thermal Oxidation Using Microscopic Raman Spectroscopy

MRS Proceedings ◽

10.1557/proc-226-345 ◽

1991 ◽

Vol 226 ◽

Cited By ~ 3

Author(s):

Hideo Miura ◽

Hiroshi Sakata ◽

Shinji Sakata Merl

Keyword(s):

Residual Stress ◽

Raman Spectroscopy ◽

Tensile Stress ◽

Oxide Film ◽

Film Thickness ◽

Silicon Dioxide ◽

Thermal Oxidation ◽

Silicon Substrate ◽

Nitride Film ◽

Oxide Film Thickness

AbstractThe residual stress in silicon substrates after local thermal oxidation is discussed experimentally using microscopic Raman spectroscopy. The stress distribution in the silicon substrate is determined by three main factors: volume expansion of newly grown silicon–dioxide, deflection of the silicon–nitride film used as an oxidation barrier, and mismatch in thermal expansion coefficients between silicon and silicon dioxide.Tensile stress increases with the increase of oxide film thickness near the surface of the silicon substrate under the oxide film without nitride film on it. The tensile stress is sometimes more than 100 MPa. On the other hand, a complicated stress change is observed near the surface of the silicon substrate under the nitride film. The tensile stress increases initially, as it does in the area without nitride film on it. However, it decreases with the increase of oxide film thickness, then the compressive stress increases in the area up to 170 MPa. This stress change is explained by considering the drastic structural change of the oxide film under the nitride film edge during oxidation.

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Fretting wear behavior of thermal-oxidation on titanium alloy in air and vacuum atmosphere

International Journal of Modern Physics B ◽

10.1142/s0217979221501356 ◽

2021 ◽

pp. 2150135

Author(s):

Liangliang Sheng ◽

Xiangtao Deng ◽

Hao Li ◽

Yuxuan Ren ◽

Guoqing Gou ◽

...

Keyword(s):

Wear Resistance ◽

Titanium Alloy ◽

Thermal Oxidation ◽

Wear Behavior ◽

Fretting Wear ◽

Partial Slip ◽

Ti6al4v Titanium Alloy ◽

Slip Regime ◽

Air Atmosphere ◽

Vacuum Atmosphere

In this work, an in-situ XPS analysis test combined self-designed high precision fretting wear tester was carried out to study the fretting wear behavior and the resulting tribo-oxidation of thermal-oxidation film on Ti6Al4V titanium alloy under the varied working atmosphere. The fretting-induced tribo-oxidation under the air and vacuum ([Formula: see text] Pa) environment was analyzed and its response on the resulting fretting wear resistance and damage mechanism was discussed. Results show that the working environment plays a significant role in the formation of tribo-oxidation and then determining the fretting wear resistance. Thermal-oxidation film in the vacuum atmosphere shows a better fretting wear resistance than that in the air atmosphere for all fretting regimes, except for partial slip regime (PSR) where there is an equivalent fretting wear resistance. Compared with the substrate Ti6Al4V titanium alloy, the thermal-oxidation film in the vacuum atmosphere performs a good protection for titanium alloy, especially for slip regime (SR), but not applied for air atmosphere.

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Effect of Temperature and Sisal Fiber Content on the Properties of Plaster of Paris

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.20.25927 ◽

2018 ◽

Vol 7 (4.20) ◽

pp. 205 ◽

Cited By ~ 1

Author(s):

Aqil M. ALmusawi ◽

Thulfiqar S. Hussein ◽

Muhaned A. Shallal

Keyword(s):

Mechanical Properties ◽

Elevated Temperatures ◽

Physical And Mechanical Properties ◽

Fiber Content ◽

Sisal Fiber ◽

Effect Of Temperature ◽

Plaster Of Paris ◽

Micro Cracks ◽

Recent Developments ◽

Negative Effect

Recent developments in the production of ecologically friendly building composites have led to a renewed interest in the use of vegetable fibers as a reinforcement element. Traditional pure Plaster of Paris (POP) can suffer from the development of micro-cracks due to thermal expansion. Therefore, sisal fiber was studied for its potential as an ecological element to restrict and delay the development of micro-cracks in POP. Different sisal proportions of 0, 2, 4, 6, 8 and 10 wt. % of POP were used to characterize the physical and mechanical properties of POP at the ambient temperature. Then, the effects of temperatures of 25, 100, 200, 300, 400 and 500 were investigated. Results proved that the composite of 10% sisal fiber had the best mechanical properties. Also, when the fiber content was increased, the composite’s performance was enhanced, becoming better able to resist elevated temperatures. However, raising the temperature to 300 or above had a negative effect on the mechanical properties, which were significantly decreased due to the degradation of the sisal fiber.

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Erosion of thin carbon layer on metal surface by hydrogen ion bombardment at elevated temperatures

Journal of Nuclear Materials ◽

10.1016/0022-3115(85)90085-6 ◽

1985 ◽

Vol 135 (2-3) ◽

pp. 260-264 ◽

Cited By ~ 5

Author(s):

Hirotaka Ohno ◽

Kenji Morita ◽

Yuji Horino ◽

Noriaki Itoh

Keyword(s):

Metal Surface ◽

Elevated Temperatures ◽

Ion Bombardment ◽

Carbon Layer ◽

Hydrogen Ion ◽

Thin Carbon

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Thermal Stability Study of the Interconnect System with Fluorinated Silicate Glass as IMD Layers

MRS Proceedings ◽

10.1557/proc-476-261 ◽

1997 ◽

Vol 476 ◽

Cited By ~ 4

Author(s):

Weidan Li ◽

Wilbur Catabay

Keyword(s):

Thermal Stability ◽

Oxide Film ◽

Silicate Glass ◽

Elevated Temperatures ◽

Stability Test ◽

Silicon Nitride Film ◽

Barrier Materials ◽

Device Reliability ◽

Interconnect System ◽

Thermal Stability Of

AbstractWhile fluorinated silicate glass (FSG) has been proposed for low k inter-metal dielectric (IMD) applications in a multi-level interconnect system either as the only IMD material, or as one of the materials for a multi-layer IMD system, thermal stability of the FSG film and its impact on device reliability remain a concern for this application. In this study, SIMS, SEM, and optical microscope analyses were carried out to evaluate the thermal stability of the FSG films and the possible reactions between FSG and metals. It was observed that at elevated temperatures fluorine tends to diffuse into an undoped oxide film rather than be desorbed. The data indicate that F diffuses 3.5 times faster in a silicon oxide film than in a silicon nitride film. Sub-half micron devices were processed with FSG as IMD layers. The devices were tested using an intensive thermal stability test methodology. A TiSi2 reaction with F which diffused from the FSG film was observed under optical microscopy. This reaction caused TiSi2 delamination. Electrical characterization of devices was performed before and after the thermal stability test. Although the device performance did not change greatly, the reaction certainly affects the long term device reliability (vide infra). Barrier materials were investigated to solve the F diffusion problem. With the proper diffusion barrier, the problem of the fluorine reaction with TiSi2 and subsequent metal blistering was eliminated.

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Synthesis of CuO nanowires on Cu-foil using thermal oxidation method, a novel annealing process

Modern Physics Letters B ◽

10.1142/s0217984916500391 ◽

2016 ◽

Vol 30 (05) ◽

pp. 1650039 ◽

Cited By ~ 1

Author(s):

Hosein Eshghi ◽

Mehdi Torabi Goodarzi

Keyword(s):

Electron Microscopy ◽

Thermal Oxidation ◽

Cupric Oxide ◽

Band Gap Energy ◽

Optical Investigation ◽

Spectra Analysis ◽

Oxidation Method ◽

Cuo Nanowires ◽

Air Atmosphere ◽

Crystallite Sizes

Cupric oxide (CuO) nanowires (NWs) on Cu-foils were prepared by thermal oxidation method in air atmosphere using two annealing manners (continuous and steps) in the temperature ranges of 400–500[Formula: see text]C and 400–600[Formula: see text]C. Morphology and microstructure of the NWs was studied using field effect scanning electron microscopy (FESEM), X-ray diffractogram (XRD), transmission electron microscopy (TEM) and selected area electron diffraction (SAED). Optical reflectance spectrum was used for the optical investigation of the layers. We found the NWs formed have two different morphologies, curved and straight, with diameters between 50 nm and 200 nm and lengths between 5 [Formula: see text]m and 10 [Formula: see text]m. SAED pattern of a single NW revealed as a CuO single crystal with monoclinic structure. The reflectance spectra analysis based on Kubelka–Munk method showed that the band gap energy of the CuO NWs are varying in the range of 1.40–1.47 eV depending on the crystallite sizes of the NWs, a confirmation for the happening of the quantum confined effect in these samples.

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