Surface Reactions of Extreme Pressure Additive on Steel Surface in Ceramics-Steel Couples

1988 ◽  
Vol 110 (3) ◽  
pp. 394-401 ◽  
Author(s):  
Y. Tanita ◽  
F. Honda ◽  
K. Nakajima
Keyword(s):  
Steel Surface ◽  
Iron Phosphate ◽  
Atomic Ratio ◽  
Sliding Contact ◽  
Chemical Compositions ◽  
Reaction Products ◽  
Antiwear Properties ◽  
Zinc Dithiophosphate ◽  
Steel Surfaces ◽  
Constituent Elements

The behavior of zinc dithiophosphate (ZnDTP) is investigated for the antiwear properties in SiC-steel and Si3N4-steel sliding contact systems under boundary lubrication. Reaction products formed on the steel surfaces under the sliding contact differ in the chemical compositions and the thickness between these couples. These differences are specifically related to the physical properties of mating materials such as heat conductivity and friction coefficient. The reaction products are analyzed by SEM (scanning electron microscope), EPMA (electron probe microanalysis), AES (Auger electron spectroscope), and PAS (photoacoustic spectroscopy), and it is confirmed that iron phosphate for SiC-steel and iron phosphate and zinc sulfide (or some complex compound containing equal amounts of Zn and S in atomic ratio) for Si3N4-steel couple exist on the steel surface, respectively. An examination is conducted on steel-steel couple in comparison with ceramics-steel couples, and the atomic ratio (Zn:P:S) of the constituent elements of the reaction products coincides fairly with that of SiC-steel couple.

scholarly journals THERMODYNAMIC PROPERTIES AND CHARACTERIZATIONS OF CHITOSAN NANO-PARTICLES CORROSION INHIBITION ON THE SURFACE OF MILD STEELIN PEAT WATER MEDIA

2016 ◽  
Vol 12 (1) ◽  
pp. 27
Author(s):  
Maria Erna ◽  
Emriadi Emriadi ◽  
Admin Alif ◽  
Syukri Arief
Keyword(s):  
Thermodynamic Properties ◽  
Mild Steel ◽  
Corrosion Inhibition ◽  
Steel Surface ◽  
Complex Compounds ◽  
Nano Particles ◽  
Water Media ◽  
Weight Loss Method ◽  
Steel Surfaces ◽  
Loss Method

The thermodynamic properties and characterizations of corrosion inhibition of chitosan nano-particles on the surface of mild steel in peat water media had been studied using weight loss method at temperatures of 30 - 50 <sup>o</sup>C. Steel surfaces were characterized by FT-IR spectra and SEM-EDS morphology photos. The research found that the value of DG<sup>o </sup>approaching -40 kJmol<sup>-</sup><sup>1</sup>. The negative value of Gibbs free energy shows that the adsorption of inhibitor molecules on the surface of mild steel was achemisorption and it occurred spontaneously. Meanwhile, the values of DH<sup>o </sup>is also negative confirming that the adsoprtion of inhibitor molecules is an exothermic process. The value of DS<sup>o </sup>obtained is positive, it indicates hat the inhibitor molecules were adsorbed spontaneously on the mild steel surface. The analysis on mild steel surfaces hows that the nano-particle chitosan was adsorbed on the steel surface to form the complex compounds.

scholarly journals Evaluation of stabilization of steel surface corrosion by paints

2005 ◽  
Vol 53 (5) ◽  
pp. 31-38
Author(s):  
Aleš Dvořák ◽  
Marta Ščerbejová
Keyword(s):  
Standardized Tests ◽  
Laboratory Experiments ◽  
Steel Surface ◽  
Water Soluble ◽  
Test Method ◽  
Surface Corrosion ◽  
Steel Surfaces ◽  
Micro Analysis ◽  
Sem Test

This article deals with laboratory experiments focused on protective and stabilizing effects of paints designed to protect rusted steel surfaces. Two well-known paints (the Hammerite No.1 Rustbeater synthetic paint and the Antirezin water-soluble paint) have been evaluated. The standardized tests according to ČSN have been used for the evaluation. Stabilization of rusted steel surface hasn’t been demonstrated during the tests. The SEM test method that covers micro-analysis of elements has been used for the evaluation as well.

scholarly journals Application of the Statistical Oxidation Model (SOM) to Secondary Organic Aerosol formation from photooxidation of C<sub>12</sub> alkanes

2013 ◽  
Vol 13 (3) ◽  
pp. 1591-1606 ◽  
Author(s):  
C. D. Cappa ◽  
X. Zhang ◽  
C. L. Loza ◽  
J. S. Craven ◽  
L. D. Yee ◽  
...  
Keyword(s):  
Formation Process ◽  
Secondary Organic Aerosol ◽  
Organic Aerosol ◽  
Atomic Ratio ◽  
Model Parameters ◽  
Reaction Products ◽  
Aerosol Formation ◽  
Volatile Organic ◽  
Oxidation Model ◽  
Mechanism Of Oxidation

Abstract. Laboratory chamber experiments are the main source of data on the mechanism of oxidation and the secondary organic aerosol (SOA) forming potential of volatile organic compounds. Traditional methods of representing the SOA formation potential of an organic do not fully capture the dynamic, multi-generational nature of the SOA formation process. We apply the Statistical Oxidation Model (SOM) of Cappa and Wilson (2012) to model the formation of SOA from the formation of the four C12 alkanes, dodecane, 2-methyl undecane, cyclododecane and hexylcyclohexane, under both high- and low-NOx conditions, based upon data from the Caltech chambers. In the SOM, the evolution of reaction products is defined by the number of carbon (NC) and oxygen (NO) atoms, and the model parameters are (1) the number of oxygen atoms added per reaction, (2) the decrease in volatility upon addition of an oxygen atom and (3) the probability that a given reaction leads to fragmentation of the molecules. Optimal fitting of the model to chamber data is carried out using the measured SOA mass concentration and the aerosol O:C atomic ratio. The use of the kinetic, multi-generational SOM is shown to provide insights into the SOA formation process and to offer promise for application to the extensive library of existing SOA chamber experiments that is available.

Friction and Wear of MoS2 Films on Etched Steel Surfaces

2008 ◽  
Author(s):  
V. Perfilyev ◽  
A. Moshkovich ◽  
K. Lutudjean ◽  
L. Rapoport
Keyword(s):  
Chemical Treatment ◽  
Friction And Wear ◽  
Steel Surface ◽  
Solid Lubricant ◽  
Surface Texturing ◽  
Roughness Parameters ◽  
Wear Properties ◽  
Wear Life ◽  
Steel Surfaces ◽  
Friction And Wear Properties

Surface texturing is one of modern technologies using for improvement friction and wear properties of rubbed surfaces. The simple and effective methods of surface texturing are mechanical or chemical treatments of friction surfaces. In this work we deal with chemical treatment of steel surfaces with following filling the profile by solid lubricant particles as MoS2. The steel surfaces were etched with phosphoric acid. The effect of time and temperature of etching on the surface roughness parameters was studied. Some standard roughness parameters of etched surface were measured. It was found that the parameters of roughness as Rz and Sm characterizing the depth of valleys and their size can be used for description of etched surfaces. Optimal parameters, Rz and Sm, providing the best tribological properties were determined: Rz = 5 ∼ 7 m and Sm = 50–70 m. The thickness of solid lubricant film was about 1 m. Finally, the tribological properties of MoS2 films on the steel surfaces textured by chemical treatment were performed. The friction coefficient and wear life of solid lubricant films was assessed. Friction and wear properties of MoS2 films on etched surfaces were compared with similar films on virgin steel surface. The wear life of MoS2 films on etched surfaces was 5–7 times larger than for solid lubricant film on mechanically treated steel surface.

Development of polyurethane-based superhydrophobic coatings on steel surfaces

2020 ◽  
Vol 378 (2167) ◽  
pp. 20190446 ◽  
Author(s):  
Mukesh Kumar Meena ◽  
Balraj Krishnan Tudu ◽  
Aditya Kumar ◽  
Bharat Bhushan
Keyword(s):  
Contact Angle ◽  
Steel Surface ◽  
Mechanical Stability ◽  
Industrial Applications ◽  
Angle Measurement ◽  
Coated Steel ◽  
Corrosion Properties ◽  
Static Contact ◽  
Steel Surfaces ◽  
Self Cleaning

In this study, a superhydrophobic coating on steel surface has been developed with polyurethane, SiO 2 nanoparticles and hexadecyltrimethoxysilane by using a spin-coating technique. Characterization of the coated steel surface was done by using the contact angle measurement technique, scanning electron microscopy and Fourier transform infrared spectroscopy. With a water tilt angle of 4° ± 2° and static contact angle of 165° ± 5°, the coated surface shows a superhydrophobic and self-cleaning nature. Chemical, thermal, mechanical stability tests and droplet dynamic studies were done to evaluate performance of the coating. Excellent self-cleaning, anti-fogging and anti-corrosion properties of coated steel surfaces make them ideal for industrial applications. This article is part of the theme issue ‘Bioinspired materials and surfaces for green science and technology (part 3)’.

scholarly journals Bacterial Phosphating of Mild (Unalloyed) Steel

2000 ◽  
Vol 66 (10) ◽  
pp. 4389-4395 ◽  
Author(s):  
Hans-Peter Volkland ◽  
Hauke Harms ◽  
Beat Müller ◽  
Gernot Repphun ◽  
Oskar Wanner ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Iron Oxides ◽  
Driving Force ◽  
Steel Surface ◽  
Surface Reaction ◽  
Bacterial Activity ◽  
Initial Value ◽  
Steel Surfaces ◽  
Steel Electrodes ◽  
Unalloyed Steel

ABSTRACT Mild (unalloyed) steel electrodes were incubated in phosphate-buffered cultures of aerobic, biofilm-formingRhodococcus sp. strain C125 and Pseudomonas putida mt2. A resulting surface reaction leading to the formation of a corrosion-inhibiting vivianite layer was accompanied by a characteristic electrochemical potential (E) curve. First, E increased slightly due to the interaction of phosphate with the iron oxides covering the steel surface. Subsequently, E decreased rapidly and after 1 day reached −510 mV, the potential of free iron, indicating the removal of the iron oxides. At this point, only scattered patches of bacteria covered the surface. A surface reaction, in which iron was released and vivianite precipitated, started. E remained at −510 mV for about 2 days, during which the vivianite layer grew steadily. Thereafter, E increased markedly to the initial value, and the release of iron stopped. Changes in E and formation of vivianite were results of bacterial activity, with oxygen consumption by the biofilm being the driving force. These findings indicate that biofilms may protect steel surfaces and might be used as an alternative method to combat corrosion.

The real contact area between composite and steel surfaces in sliding contact

2001 ◽  
Vol 61 (13) ◽  
pp. 1853-1862 ◽  
Author(s):  
Károly Váradi ◽  
Zoltán Néder ◽  
Klaus Friedrich ◽  
Joachim Flöck
Keyword(s):  
Contact Area ◽  
Sliding Contact ◽  
Real Contact Area ◽  
The Real ◽  
Real Contact ◽  
Steel Surfaces

New Method of Quench Surface Turning

2017 ◽  
Vol 265 ◽  
pp. 696-701 ◽  
Author(s):  
N.N. Zubkov ◽  
S.G. Vasil'ev ◽  
V.V. Poptsov
Keyword(s):  
Phase Transformation ◽  
Steel Surface ◽  
Hardened Steel ◽  
Surface Structures ◽  
Heating And Cooling ◽  
Surface Quenching ◽  
Steel Surfaces ◽  
Deformational Cutting ◽  
Chip Separation ◽  
Hardened Surface

The heating, generated in the process of deformational cutting without chip separation used for phase transformation in steel during lathe machining. Chips are not separated from the workpiece and remain on the surface thus forming a special reinforced structure. The result of processing is a steel surface quenching up to 1 mm deep. The proposed method also makes it possible to obtain hardened surface structures with alternating inclined layers of different hardness. The article presents calculations of heating and cooling rates, types of hardened structures, hardness investigation of hardened steel surfaces.

Contact and thermal analysis of transfer film covered real composite-steel surfaces in sliding contact

2000 ◽  
Vol 33 (11) ◽  
pp. 789-802 ◽  
Author(s):  
Károly Váradi ◽  
Zoltán Néder ◽  
Klaus Friedrich ◽  
Joachim Flöck
Keyword(s):  
Thermal Analysis ◽  
Transfer Film ◽  
Sliding Contact ◽  
Steel Surfaces ◽  
Composite Steel
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