Papers by Keyword: Oxide Film

Paper TitlePage

Authors: Zhen Ying Huang, Hong Xiang Zhai, Ming Xing Ai
Abstract: The tribological behavior of a new cermet Ti3AlC2/Cu was experimentally investigated. The results showed that the Ti3AlC2/Cu was a good tribological material sliding against the low carbon steel, especially for a high sliding speed. The friction coefficient was as low as 0.13 ~ 0.15, and the Ti3AlC2/Cu wear rate was only 3.4×10-6 mm3/Nm, for the sliding speed of 60 m/s and the normal pressure of 0.8 MPa. The forming of a frictional film consisted of Ti, Al, Cu and Fe oxides on the friction surfaces could be a fundamental cause.
1436
Authors: Ji Cai Kuai
Abstract: The adhesion property of oxide film has great effects on the grinding quality and efficiency of ELID grinding. In this paper, adhesion strength model of oxide film is established, ELID grinding is conducted to nanometric cemented carbide and ordinary cemented carbide, ELID grinding force is measured, adhesive stress is calculated and the correctness of adhesion model is verified. The results show that the adhesion strength of oxide film is relatively greater, the transition from γ-Fe2O3 to α-Fe2O3 in the oxide film is relatively fuller and the polishing performance is relatively better while the grinding depth is smaller; with the deepening of grinding, the adhesion strength of oxide film reduces, the composition of the oxide film that transforms into α-Fe2O3 is less and the polishing ability reduces. The adhesion model of oxide film well reflects the adhesion property of oxide film, and the application of this model can represent the distribution, shedding and updating of the oxide film on the surface of grinding wheel.
557
Authors: Shinji Koyama, Makoto Takahashi, Kenji Ikeuchi
Abstract: The bond interface of a TLP (Transient Liquid Phase) bonded tin has been observed with a TEM to investigate the effect of the liquid phase on the behavior of the superficial oxide film at the interface during the bonding process. In the solid-state-diffusion bonded joint without filler, abundant oxide inclusions were observed to be distributed within a region of a few 100 nm widths along the bond interface. In comparison with this, the liquid phase introduced by the eutectic reaction of the bismuth filler with the tin substrate decreased the width of the interfacial region involving abundant oxide inclusions to form a rather layer structure a few 100 nm thick consisting mainly of SnO2. It also enhanced the annihilation of the uncontacted areas at the interface. The layer of the oxide became discontinuous and coalesced with an increase in bonding temperature and pressure, and areas where no oxide inclusion could be observed at the interface were increased, when the liquid phase was formed. Owing to these effects, the bond strength rose at lower bonding temperatures and pressures when the bismuth filler was applied.
3503
Authors: Toha Nor Fadzilah, Siti Norbahiyah, Mohd Zain Mohamad Zamzuri
Abstract: An oxide film was prepared on AZ91D magnesium alloy by anodizing in solution containing sodium metavanadate (NaVO3). The corrosion resistance of the AZ91D magnesium alloy was investigated at fixed current density 10 mA/cm2 for 5 min with different concentration of solution in the range of 0 1.0 g/l. The surface morphology, cross section morphology, phase structure, and surface roughness of oxide film were studied by optical microscope, scanning electron microscope (SEM) and energy dispersive spectrometry (EDS), atomic force microscope (AFM) and potentiodynamic polarization technique and corrosion test, respectively.
55
Authors: Akira Kai, Yuichiro Terayama, Kazuhiro Ogawa, Tetsuo Shoji
2806
Authors: Yo-ichi Takeda, M. Bojinov, Hannu Hänninen, P. Kinnunen, T. Laitinen, K. Mäkelä, T. Saario, K. Sakaguchi, Tetsuo Shoji, P. Sirkiä, A. Toivonen
Abstract: A possible approach to describe the role of the environment in the phenomena behind crack initiation and crack propagation in stress corrosion cracking (SCC) is to assume that the transport of species through the oxide film on the material surface is one of the rate-controlling factors. The transport rates of ionic and electronic defects through the oxide film are, in addition to the environment, also affected by the stress and strain applied to the bulk material. In this paper, the surface oxide film formed on AISI 316L steel in slow strain rate tests (SSRT) in simulated BWR condition has been analyzed by using Electron Spectroscopy for Chemical Analysis (ESCA). The obtained film composition and structure have been combined with in-situ contact electric resistance (CER) measurements in order to evaluate the changes in oxide film electric properties during straining in the above environment. The results show that oxide film resistance of the strained part exhibits a maximum at around 2% of strain, which seems to correlate with a maximum in the Cr(III) concentration in the inner layer of the oxide. The implications of these results to SCC are discussed based on Mixed-Conduction Model (MCM).
925
Authors: Hong Fang Ma, Ming Zhu, Qing Zhu, Yan Li
Abstract: In solar thermal storage system, the mixed chloride molten salt with the higher conversion efficiency than a single molten salt, but they are more corrosive than the often used nitride molten salts. In the presents work, aluminide and chromate coating were prepared on the surface of Inconel625 alloy by thermal packing method. The corrosion behaviors of thermal diffusion coating on the surface of Inconel625 alloy in mixed molten salts at 900°C were studied by using XRD and SEM equipped with EDS in the present work. The results showed that both of the two thermal diffusion coatings have sever corrosion in the mixed chloride molten salts, but thermal diffusion Al coating in the mixed chloride molten salt corrosion is more serious than thermal diffusion Cr coating, because Cr2O3 is more easily dissolved in the molten salt than Al2O3.
589
Authors: Toha Nor Fadzilah, S. Norbahiyah, Mohd Zain Mohamad Zamzuri
Abstract: An oxide film was prepared on AZ91D magnesium alloy by anodizing in solution containing sodium metavanadate (NaVO3). The corrosion resistance of the substrate was investigated at a fixed current density 10 mA/cm2 for 5 mins with different concentration of solution in the range of 0 – 1.0 g/l. The surface morphology, phase structure and corrosion resistance of oxide film were studied by optical microscope, scanning electron microscope (SEM) and energy dispersive spectrometry (EDS) and X-ray diffractometer (XRD), potentiodynamic polarization technique and corrosion test.
170
Authors: Si Xian Rao, Su Ping Yang, Ji Bin Tong, Jing Ru Wang
Abstract: Cracking behaviors of oxide films on A3, 30CrMnSiA steel under applied stress were investigated in this paper. Theoretical deductions confirmed that critical cracking conditions for oxide films on A3 and 30CrMnSiA steel did exist. Electrochemical tensile experiments in 3%NaCl aqueous solution showed that the critical cracking stress for oxide film on A3 steel is about 220MPa,the critical cracking stress for oxide film on 30CrMnSiA steel is about 80MPa.In-situ dynamic tensile experiments verified the correctness of the experiments results in the electrochemical tensile experiments.
671
Authors: Li Wu Huang, Yeong Jern Chen, Teng Shih Shih, Lih Ren Hwang
Abstract: Pure aluminum ingot (99.8 wt%) was melted to prepared chilled samples in this study. These samples were then removed to polish their surfaces and put in an ultrasonic cleaner filled with tap water. The polished surface would gradually show foggy marks after being subjected to a period of treating time. Oxide films, if entrapped, would crack, erode and detach from the chilled sample forming foggy marks on the polished surface. The sample then removed to measure oxygen and aluminum concentrations varied along the transition layer between the oxide film and aluminum matrix. Part of chilled samples was melted in a muffle furnace and subjected to different holding time. As the holding time increased, the transition layer between the oxide film and the matrix was increased and composed of different constituents varying from the Al matrix to the oxide film (mainly γ-Al2O3). This transition layer also showed different hardness measured by a nano-hardness tester. The morphologies of cracked oxide film and the eroded oxide particles were affected by the holding time after melted, and small amounts of silicon in the pure aluminum.
1311
Showing 1 to 10 of 55 Paper Titles