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Micro void coalescence of ductile fracture in mild steel during tensile straining  [PDF]
P. K. Pradhan,P. R. Dash,P. S. Robi,Sankar K. Roy
Frattura ed Integrità Strutturale , 2012,
Abstract: The ductile fracture occurs mainly in three stages i.e. void nucleation, void growth and the void coalescence. The present work focuses on the study the coalescence of existing micro void in a ductile material, mild steel. The specimen with holes in square array at various angle to load axis have been tested. The holes were machined in the specimen and assuming those hole as the voids. The growth and coalescence behaviours during tensile straining were observed both in macro and micro levels. Since the existing facility is not adequate to make hole size in micron, this work has been carried out by making hole upto 500 micron. The results are compared with other specimen with bigger size hole and without any hole. Also the effects of micro voids (present in the material) on the progress of crack have been studied. It is found that with same amount of voids, present in different positions, the mechanical properties of the material are altered.
Evaluation of Rubber/Mild Steel Bonds Failure after Exposure in Marine Environment
Ismaliza Ismail,M. K. Harun
International Journal of Chemical Engineering and Applications , 2013, DOI: 10.7763/ijcea.2013.v4.276
Abstract: The use of rubber/metal bonded composite is growing in the offshore industries as well as in the automotive components. Maintaining a good adhesion between rubber to substrate bond is a crucial importance in ensuring a satisfactory product performance in service. Bond failure attributes to the severe product performance failure. Exposure under salt environment can cause the bond failure due to corrosion reaction. Therefore the durability of rubber/metal bond in seawater, using natural rubber bonded to mild steel by proprietary bonding agent is studied. The locus of failures was determined at primer/metal oxide layer and the results are presented in the SEM and EDS analysis on both of the interfacial failures area. The adhesion failure mechanism is proposed where the bond delamination was found precedes the under film corrosion.
Effect of Hydroxyl Silicate particulates as an Additive on the Friction and Wear Behavior of Mild Steel/Ductile Cast Iron Pair
羟基硅酸盐润滑油添加剂对45#钢/球墨铸铁摩擦副摩擦磨损性能的影响

GUO Yan-bao,XU Bin-shi,MA Shi-ning,XU Yi ed Force Engineering,Beijing,China,
郭延宝
,徐滨士,马世宁,许一

摩擦学学报 , 2004,
Abstract: An MM-200 friction and wear tester was performed to evaluate the friction and wear behavior of 1045 steel/ductile cast iron pair under the lubrication of 650SN oil and the 650SN containing hydroxyl silicate particulates as the additive (The latter oil specimen was coded as KF-1). The worn surface and cross-section of the AISI1045 steel block were observed using a scanning electron microscope, and the elemental composition on the worn surface of the steel block was examined using an energy dispersive X-ray analyzer. It was found that the inorganic mineral particulates as the additive led to increased friction coefficient and wear volume loss of the ductile cast iron ring at a relatively shorter test duration, which was attributed to the abrasion action of the particulates. The friction and wear of the frictional pair under the lubrication of KF-1 was significantly decreased at an extended test duration, which was attributed to the embedding strengthening effect of the inorganic particulates to the worn steel surface. Namely, a friction-modified layer was formed on the worn steel surface under the lubrication of the KF-1, and the relevant worn steel surface had a much larger microhardness than the one under the lubrication of the base stock alone. At the same time, the surface-modified layer in the former case was porous, which helped to entrap the lubricating oil therein and to enhance the boundary lubricating function as well. Subsequently, the friction and wear of the frictional pair was greatly decreased at a large enough test duration.
IMPACT STRENGTH AND FAILURE ANALYSIS OF WELDED DAMASCUS STEEL
Rastislav Mintách,Franti?ek Novy,Otakar Bok?vka,Mária Chalupová
Materials Engineering , 2012,
Abstract: The aim of this work was the experimental research of damascus steel from point of view of the structural analyze, impact strength and failure analyzes. The damascus steel was produced by method of forged welding from STN 41 4260 spring steel and STN 41 9312 tool steel. The damascus steel consisted of both 84 and 168 layers. The impact strength was experimentally determined for original steels and damascus steels after heat treatment in dependence on temperature in the range from -60 to 160 °C. It has been found that the impact strength of experimental steels decreased with decreasing temperature behind with correlated change of damage mode. In the case of experimental tests performed at high temperature ductile fracture was revealed and with decreasing temperature proportion of cleavage facets increased. Only the STN 41 9312 steel did not show considerable difference in values of the impact strength with changing temperature.
Ductile Fracture Characterization for Medium Carbon Steel Using Continuum Damage Mechanics  [PDF]
Stergios Pericles Tsiloufas, Ronald Lesley Plaut
Materials Sciences and Applications (MSA) , 2012, DOI: 10.4236/msa.2012.311109
Abstract: This paper presents the ductility characterization for a medium carbon steel, for two microstructural conditions, that has been evaluated using the continuum damage mechanics theory, as proposed by Kachanov and developed by Lemaitre. Tensile tests were carried out using loading-unloading cycles in order to capture the gradual deterioration of the elastic modulus, which may be linked to the ductile damage increase with increasing plastic strain. The mechanical parameters for the isotropic damage evolution equation were obtained and then used as inputs for a plasticity-damage coupled nu- merical algorithm, validated through numerical simulations of the experimental tensile tests. A comparison between the SAE 1050 steels studied and two carbon steel alloys (obtained from the literature), provided some basic understanding of the influence of the carbon level on the evolution of the damage parameters. An empiric relationship for this set of parameters, which can provide useful data for preliminary studies envisaging prediction of ductile failure in carbon steels, is also presented.
Aluminising of Mild Steel Plates  [PDF]
Udaya Bhat Kuruveri,Prashanth Huilgol,Jithin Joseph
ISRN Metallurgy , 2013, DOI: 10.1155/2013/191723
Abstract: Hot dip aluminising of low carbon steel was done at temperatures 690°C and 750°C for dipping time ranging from 300 to 2400 seconds. During aluminising a mixture of ZnCl2 and NH4Cl was used as flux. During aluminising components of the flux decomposed and zinc formed interacted with the Fe and Al. The aluminised samples were characterised for iron-aluminium intermetallic layer formation, morphology, and local composition. It was observed that intermetallic layer was predominantly Fe2Al5 and FeAl3 at 690°C and at 750°C coating consisted of FeAl3 layer and a layer with Al/Fe ratio greater than 3.26. For both temperatures, coating thickness increased with increase in time. For a given dipping time, deposition was less at higher temperature and this is attributed to changes in the kinetics of growth of individual layers due to dissolved zinc in the aluminium, at 750°C. Also, spalling of intermetallic layers was observed at elevated temperatures and longer dipping times. 1. Introduction Steel remains the material of choice for numerous applications, largely because of its low cost and wide variety of properties available through alloy design, heat treatment, and amenability for forming operations [1]. The oxide layer forming on the steel substrate is a noncompact one and due to this conventional mild steel exhibits poor oxidation and corrosion resistance properties. To improve corrosion properties, the steel can be alloyed with various elements such as chromium and nickel, but this increases material cost and limits width of the processing window [1]. Alternate route is to modify the surface of the steel appropriately, so that it can replace expensive alloy steel material [2]. During surface modification, the surface of the steel material is modified over a relatively shallow depth, using an appropriate method. When a suitable technique is selected and correctly done, the following properties of the steel can be increased: resistance to wear, chemical resistance, mechanical resistance, and oxidation resistance [3, 4]. Among various surface modification methods available for steel, the hot dipping process has drawn much attention because it is an effective and inexpensive process. In this context, use of aluminium as a coating material is highly relevant because, aluminium, when applied to steel provides corrosion resistance layer [5]. Also, aluminium bearing steels can be easily nitrided and nitrided steel has better wear and fatigue properties. Continuous alumina layer is highly resistant to oxidation, sulfidation, and degradation in chloride containing
ADSORPTION OF METHIONINE ON MILD STEEL
ABIOLA,OLUSEGUN K;
Journal of the Chilean Chemical Society , 2005, DOI: 10.4067/S0717-97072005000400008
Abstract: the adsorption of methionine at the mild steel surface from acidic solutions is studied using gravimetric technique. the adsorbability of methionine (values of surface coverage) depends on the nature of the acid and the concentration of methionine. the surface coverage with the adsorbed methionine is used to calculate the free energy of adsorption, dg0ad of methionine using bockris - swinkel isotherm. the dependence of free energy of adsorption, dg0ad with surface coverage, q is ascribed to surface heterogeneity of the adsorbent. the effect of methionine is discussed from the viewpoint of adsorption model. the adsorption of methionine molecules on the surface occurs without modifying the kinetic of corrosion process
ADSORPTION OF METHIONINE ON MILD STEEL  [cached]
OLUSEGUN K ABIOLA
Journal of the Chilean Chemical Society , 2005,
Abstract: The adsorption of methionine at the mild steel surface from acidic solutions is studied using gravimetric technique. The adsorbability of methionine (values of surface coverage) depends on the nature of the acid and the concentration of methionine. The surface coverage with the adsorbed methionine is used to calculate the free energy of adsorption, DG0ad of methionine using Bockris - Swinkel isotherm. The dependence of free energy of adsorption, DG0ad with surface coverage, q is ascribed to surface heterogeneity of the adsorbent. The effect of methionine is discussed from the viewpoint of adsorption model. The adsorption of methionine molecules on the surface occurs without modifying the kinetic of corrosion process
Atmospheric corrosion of mild steel  [cached]
Morcillo, M.,de la Fuente, D.,Díaz, I.,Cano, H.
Revista de Metalurgia , 2011,
Abstract: The atmospheric corrosion of mild steel is an extensive topic that has been studied by many authors in different regions throughout the world. This compilation paper incorporates relevant publications on the subject, in particular about the nature of atmospheric corrosion products, mechanisms of atmospheric corrosion and kinetics of the atmospheric corrosion process, paying special attention to two matters upon which relatively less information has been published: a) the morphology of steel corrosion products and corrosion product layers; and b) long-term atmospheric corrosion ( > 10 years). La corrosión atmosférica del acero suave es un tema de gran amplitud que ha sido tratado por muchos autores en numerosas regiones del mundo. Este artículo de compilación incorpora publicaciones relevantes sobre esta temática, en particular sobre la naturaleza de los productos de corrosión atmosférica, mecanismos y cinética de los procesos de corrosión atmosférica, prestando una atención especial a dos aspectos sobre los que la información publicada ha sido menos abundante: a) morfología de los productos de corrosión del acero y capas de productos de corrosión, y b) corrosión atmosférica a larga duración (> 10 a os).
Effect of Serine and Methionine on Electrochemical Behavior of the Corrosion of Mild Steel in Aqueous Solutions  [PDF]
Mohamed N. Rahuma,Mohamed B. EL-Sabbah,Imperiyka M. Hamad
ISRN Corrosion , 2013, DOI: 10.1155/2013/895120
Abstract: The pitting corrosion behaviour of mild steel in Na2HPO4 solutions contains chloride ion as an aggressive ion and serine and methionine as inhibitors were investigated using open-circuit potential (OCP), potentiodynamic polarization measurements, and pitting corrosion current measurements; both inhibitors shift the potential in the positive direction. The corrosion rate of the mild steel was measured in the absence and presence of the inhibitors, and the inhibition efficiency of the amino acids at a concentration of 0.02?M was calculated. The pitting corrosion current shows that increasing concentration of the inhibitor causes a decrease in pitting current density, and inhibition efficiency increases with increasing concentration of the inhibitors. The adsorption of these inhibitors on the mild steel surface obeys Langmuir isotherm, and the calculated adsorption free energy (Δ ) for the inhibitors on the mild steel in 0.1?M (Na2HPO4?+?NaCl) solutions was found to be (?24.61, ?29.34)?kJ/mol for serine and methionine, respectively, which reveals strong physical adsorption of the amino acids molecules on the mild steel surface. 1. Introduction Mild steel is one of the major construction materials, which is extensively used in chemicals and industries [1, 2]. Pitting corrosion in the presence of aggressive chloride ions Cl? is the most frequently encountered cause of failure of mild steel. It is generally accepted that pitting proceeds by destruction of the protective oxide by adsorption of that subsequently passes into solution [3]. Compounds that retard or stop this process when present in aggressive medium are prospective corrosion inhibitors. Its protection against pitting corrosion has attracted much attention. One of the available methods is the use of soluble inhibitors; the use of inhibitor is one of the most practical methods to protect metals from corrosion, especially in aggressive media in particular, in chemicals, and petrochemical and oil industries [4, 5]. Unfortunately, many of the inhibitors used are inorganic salts and organic compounds, with toxic properties or limited solubility [6]. Protective action of inorganic inhibitors is related to the formation of oxide film or hardly soluble salt on the metal surface. One the other hand protective action of organic inhibitors comes from the adsorption on the oxide films. Increasing awareness of the health and ecological risks has drawn attention to finding more suitable inhibitors, which are nontoxic. Amino acids inhibitors fall into this category since they are cheap; most of them are soluble
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