scholarly journals Density Determination for Oxide Scale Formed on Steel Plate Considering Non-stoichiometry of Fe1-xO

2021 ◽  
Vol 107 (7) ◽  
pp. 551-557
Author(s):  
Saori Shinohara ◽  
Rie Endo ◽  
Takashi Watanabe ◽  
Miyuki Hayashi ◽  
Hiroshi Tanei ◽  
...  
Keyword(s):  
Oxide Scale ◽  
Steel Plate ◽  
Density Determination

Mechanism of Galling Generation Using TiCN Coating in Finish Blanking - Thermochemical Simulation and Elemental Analysis -

2019 ◽  
Vol 794 ◽  
pp. 333-339
Author(s):  
Tomohiro Yamada
Keyword(s):  
Oxide Scale ◽  
Equilibrium Problems ◽  
Steel Plate ◽  
Expansion Ratio ◽  
Surface Flow ◽  
High Tensile Strength ◽  
Electron Probe Micro Analyzer ◽  
Commercial Code ◽  
Ticn Coating ◽  
Surface Expansion

The mechanism of galling generation is studied with finish blanking using TiCN coated punch. A high-tensile-strength-steel plate with a thickness of 6mm is used in the present paper. The edge shapes of punch are two types, a punch with 1.0 mm chamfered edge (C1.0 punch) and a punch with right angle edge (RA punch). The clearance is kept to 0.5%t, and lubrication is not used in this experiment. Galling is observed at the first shearing operation except for RA punch, and galling can’t be found clearly even when the shearing number reaches 20 in the case of the RA punch. In order to clarify these differences of RA punch and C1.0 punch, the oxygen on burnished depth is observed by electron probe micro analyzer (EPMA). The oxygen is not detected on the burnished depth sheared by RA punch. On the other hand, the oxygen is detected on the burnished depth sheared by C1.0 punch. In the case of C1.0 punch, the oxide scale on the plate surface flow into the burnished depth because of the low surface expansion ratio of the burnish depth. Thermochemical simulation is carried out using a commercial code MALT and gem which solves chemical equilibrium problems by minimizing the gibbs energy of the system. TiCN reacts with oxide scale to form Fe and Fe4N. As result of analyzing galling part of C1.0 punch from the cross section direction, Fe, Fe4N, FeTiO3 and Fe2TiO4 are detected and those detected elements coincides well with the Thermochemical simulation.

Structural Imperfections in thin Oxide Films Formed on Some Fe- and Ni-Base Alloys

1970 ◽  
Vol 28 ◽  
pp. 510-511
Author(s):  
L. P. Lemaire ◽  
D. E. Fornwalt ◽  
F. S. Pettit ◽  
B. H. Kear
Keyword(s):  
Oxide Scale ◽  
Oxidation Process ◽  
Short Circuit ◽  
Protective Oxide ◽  
Protective Oxide Scale ◽  
Thin Oxide Films ◽  
Diffusion Paths ◽  
Oxidation Resistant ◽  
Structural Imperfections ◽  
Short Circuit Diffusion

Oxidation resistant alloys depend on the formation of a continuous layer of protective oxide scale during the oxidation process. The initial stages of oxidation of multi-component alloys can be quite complex, since numerous metal oxides can be formed. For oxidation resistance, the composition is adjusted so that selective oxidation occurs of that element whose oxide affords the most protection. Ideally, the protective oxide scale should be i) structurally perfect, so as to avoid short-circuit diffusion paths, and ii) strongly adherent to the alloy substrate, which minimizes spalling in response to thermal cycling. Small concentrations (∼ 0.1%) of certain reactive elements, such as yttrium, markedly improve the adherence of oxide scales in many alloy systems.

Morphologies of Nonadherent Al2O3 and Matching Substrate Surfaces

1972 ◽  
Vol 30 ◽  
pp. 524-525
Author(s):  
C. S. Giggins ◽  
J. K. Tien ◽  
B. H. Kear ◽  
F. S. Pettit
Keyword(s):  
Electron Microscopy ◽  
Oxide Scale ◽  
Oxidation Resistance ◽  
Substrate Surface ◽  
Morphological Features ◽  
Thermally Induced ◽  
Oxide Spallation ◽  
Oxidation Resistant ◽  
Induced Stresses ◽  
Substrate Surfaces

The performance of most oxidation resistant alloys and coatings is markedly improved if the oxide scale strongly adheres to the substrate surface. Consequently, in order to develop alloys and coatings with improved oxidation resistance, it has become necessary to determine the conditions that lead to spallation of oxides from the surfaces of alloys. In what follows, the morphological features of nonadherent Al2O3, and the substrate surfaces from which the Al2O3 has spalled, are presented and related to oxide spallation.The Al2O3, scales were developed by oxidizing Fe-25Cr-4Al (w/o) and Ni-rich Ni3 (Al,Ta) alloys in air at 1200°C. These scales spalled from their substrates upon cooling as a result of thermally induced stresses. The scales and the alloy substrate surfaces were then examined by scanning and replication electron microscopy.The Al2O3, scales from the Fe-Cr-Al contained filamentary protrusions at the oxide-gas interface, Fig. 1(a). In addition, nodules of oxide have been developed such that cavities were formed between the oxide and the substrate, Fig. 1(a).

Novel Electro Polymerization Method to Synthesized Anti-corrosion Coated Layer on Stainless Steel Surface from (N-Benzothiazolyl Maleamic Acid) and Study its Biological Activity

2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Muna I Khalaf ◽  
Khulood A Saleh ◽  
Khalil S Khalil
Keyword(s):  
Stainless Steel ◽  
Chemical Structure ◽  
Inhibition Efficiency ◽  
Steel Plate ◽  
Polymeric Coating ◽  
Stainless Steel Surface ◽  
Plate Electrode ◽  
Before And After ◽  
Maleamic Acid ◽  
Polymerization Method

Electro polymerization of N-benzothiazolyl maleamic acid (NBM) was carried out on stainless steel plate electrode in a protic medium of monomer aqueous solution using electrochemical oxidation procedure in electrochemical cell.Spectroscopic characterization techniques were investigated to obtain information about the chemical structure of polymer. The anti-corrosion action of polymer was investigated on stainless steel by electrochemical polarization method. In addition, the effect of adding nanomaterial (TiO2, ZnO (bulk-nano)) to monomer solution on the corrosion behavior of stainless steel was investigated. The results obtained showed that the corrosion rate of S-steel increased with temperature increase from 293K to 323K and the values of inhibition efficiency by coating polymer increase with nanomaterial addition. Apparent energies of activation have been calculated for the corrosion process of S-steel in acidic medium before and after polymeric coating. Furthermore were studied the effect of the preparing polymer on some strain of bacteria.

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