Surface Treatment Of Steel Research Articles

Electrochemical Corrosion Characteristics of High Strength Low Alloy Domex 700 Steel After Mechanical Surface Treatment in Chloride Environment

Abstract Nowadays a large number of mechanical surface treatments of constructions materials is used in industry, mainly focusing on steel surface treatment. The aim of this study was to evaluate the effects of mechanical surface pre-treatment (grinding and shot peening) on corrosion resistance of high strength low alloy Domex 700 steel. Suitable mechanical surface treatment can by used for surface homogenization (eg. grinding) or for improvement of mechanical, strength and fatigue properties (shot peening). 0,1M NaCl solution of ambient temperature was used as an environment for electrochemical tests. Evaluation of the mechanical surface treatment effect on corrosion resistance of Domex 700 steel surface was realized by electrochemical tests: potentiodynamic polarization tests (using Tafel analysis) and electrochemical impedance spectroscopy (using equivalent circuit). From the obtained results it is possible to conclude, that the process of mechanical surface treatment by shot peening at choosen conditions has negative effect on corrosion resistance of Domex 700 steel.

Influence of a steel surface treatment on the wetting angle and free surface energy

Influence of a steel surface treatment on the wetting angle and free surface energy

Screening the effect of chemical treatment of steel substrate by a composite cerium-lanthanum nanofilm on the adhesion and corrosion protection properties of a polyamide-cured epoxy coating; Experimental and molecular dynamic simulations

Abstract The steel substrate was treated by cerium-lanthanum based conversion coatings. The effects of surface treatment of steel on the interfacial adhesion, cathodic delamination and corrosion resistance of the epoxy coating were studied through experimental and computational studies. Corrosion resistance of the epoxy coating applied on the untreated and surface treated samples was evaluated by electrochemical impedance spectroscopy and salt spray test. Results of experiments revealed that post-treatment of cerium conversion coating by lanthanum gave rise to the superior corrosion resistance, low cathodic delamination rate and enhanced interfacial adhesion of the epoxy coating, in agreement with computational results. In addition, computational molecular dynamic (MD) simulations revealed that the epoxy bonding to the steel surface was remarkably enhanced by surface treatment of steel substrate by cerium conversion coating post-treated by lanthanum.

Steel surface treatment with three different acid solutions and its effect on the protective properties of the subsequent silane coating

Abstract Surface treatment of steel before application of silane coating plays important role to provide better corrosion protection. This work aims to evaluate the effect of steel surface treatment with acid solutions on the protective properties of subsequent organosilane coating. For this purpose, sulfuric, phosphoric and hydrochloric acid solutions were prepared at pH 3. The change in surface chemistry and morphology of mild steel surface after acid treatment was assessed by FE-SEM, XPS and water contact angle measurements. After surface treatment with acid solutions, a silane coating was applied on the steel samples. EIS measurements on the silane coated samples showed that the one treated by sulfuric acid solution provided better protection compared to the rest of samples.

Laser surface treatment of S235JRC carbon steel with Co2B nanocrystals

Abstract In this study, Co2B nanocrystals, which were synthesized in a planetary type mill by using the mechanochemical method, were pre-coated on the surface of S235JRC low carbon steel substrates, and then the surfaces were clad using a CO2 laser. In the experiments, laser scan speed was kept constant and laser power was specified as the variable parameter. The microstructure and phases of the coatings were investigated by using X-ray diffractometry, scanning electron microscopy, and optical microscopy. The mechanical properties of the coatings were characterized using micro-hardness, ball-on-disc wear, and scratch testing. The thickness of the coatings depending on the laser power was measured in the range 35–71 μm. The hardness and the wear resistance of the coatings were approximately 3 times higher compared to the base metal due to FeN0.0760, Fe15.1C, FeCo, and B2C5N2 phases of the coatings. The most durable coatings against wear were obtained at 174 W and 220 W laser powers.

A Detailed Molecular Dynamics Simulation and Experimental Investigation on the Interfacial Bonding Mechanism of an Epoxy Adhesive on Carbon Steel Sheets Decorated with a Novel Cerium-Lanthanum Nanofilm.

The influences of steel surface treatment by a novel cerium-lanthanum (Ce-La) nanofilm on the adhesion mechanism of an epoxy adhesive were studied through experimental and modeling approaches. The surface morphology and microstructure of the film deposited were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). The surface free energy and work of adhesion values were evaluated through contact angle analysis. Also, the interfacial adhesion strength between the epoxy adhesive and steel surface, together with failure forms, were examined through pull-off test, under dry and wet conditions, and Fourier transform infrared (FT-IR) spectroscopy. The results obtained from experiments revealed that depositing a Ce-La nanofilm on the steel surface increased its roughness and surface free energy, and strengthened the epoxy coating adhesion. It was also observed that the epoxy adhesion on the Ce-La treated steel was stronger, compared to the Ce-treated surface. Furthermore, the adhesion extent and surface bonding mechanism of aminoamide-cross-linked epoxy resin were computationally modeled by applying atomistic molecular dynamics (MD) and electronic density functional theory (DFT) methods. The modeling results evidenced that epoxy resin adhered more strongly to the conversion layer (represented by CeO2 and La2O3), compared to an untreated steel surface (i.e., pure and oxidized iron). The epoxy binding onto CeO2(111), La2O3(001), Fe2O3(110), and Fe3O4(100) almost occurred via electrostatic interactions, while its adhesion mechanism over FeO(100) and Fe(110) surfaces was based on van der Waals forces. The computations also demonstrated that the epoxy adsorption energy decreased in wet environments, because of solvent affinity toward the epoxy and the surface, but the rate of reduction was smaller over CeO2 and La2O3, compared to that observed with iron oxides. These modeling outcomes were consistent with our experiments and proposed the superior epoxy adhesion on modified steel sheets.

Laser gas assisted treatment of steel 309: Corrosion and scratch resistance of treated surface

Laser gas assisted surface treatment of steel 309 is carried out and the characteristics of the resulting surface are analyzed using the analytical tools. Scanning electron and 3-D optical microscopes are used to assess the morphological and metallurgical changes in the laser treated layer. Energy spectroscopy and X-ray diffraction are carried out to determine the elemental composition and compounds formed on the laser treated surface. The friction coefficient of the laser treated surface is measured using the micro-tribometer and compared to that of the as received surface. The corrosion resistance of the laser treated and as received surfaces is measured incorporating the electrochemical tests. It is found that laser treatment results in a dense layer and formation of nitride compounds at the surface. This enhances the microhardness at the laser treated surface. The friction coefficient attains lower values at the laser treated surface than that corresponding to the as received surface. The corrosion rate of the surface reduces significantly after the laser treatment process, which can be attributed to the passive layer at the surface via formation of a dense layer and nitride compounds in the surface vicinity. In addition, the number of pit sites decreased for the laser treated surface than that of as received surface.

Surface treatment of stainless steel by electrolytic oxidation and deposition of titanium complexing ion solution to improve metal-ceramic adhesion

Etched stainless steel plates were prepared using electrolytic oxidation while varying the applied voltage and reaction time. The morphology of the surfaces of the etched stainless steel plates was investigated using scanning electron microscopy. A hierarchical pore network with multiple pore sizes was observed on the etched surface. It is thought that these structures on the metal surface contributed to an improvement in metal-ceramic adhesion by linking with ceramic particles. Citratoperoxotitanate(IV) is a typical titanium complexing ion containing carboxyl groups. Therefore, this complex ion was expected to readily form organic-inorganic hybrid chemical bonds on the metal surface. Water-soluble citratoperoxotitanate(IV) was synthesized via a ‘peroxotitanate’ intermediate. The titanium complexing solution was mixed with a catalyst solution and the product was used to coat the stainless steel plates. The complexing ion formed chemical bonds, such as Fe-COO-Ti, on the steel surface. Improved adhesion was observed between the metal and ceramic particles, attributed to the organic-inorganic chemical bonds.

Thermal Variation During Osteotomy With Different Dental Implant Drills: A Standardized Study in Bovine Ribs.

This study evaluated thermal variation (heat generation) by dental drills of similar geometries, made from different materials, during performance of 450 standardized osteotomies in bovine ribs to simulate implant site preparations. Each of the 3 groups-steel with a diamond-like carbon coating (SG), experimentally surface-treated steel (EG), and aluminum-toughened zirconium ceramic (ZG)-included 3 drills, distributed across 6 subgroups. An implant motor provided torque, rotation, and irrigation for 50% of subgroups. In preparations drilled to 5 mm under irrigation, the number of osteotomies, material, and diameter did not influence thermal variation (ΔT); when drilling to 13 mm, the greatest ΔT occurred in EG (2.8°C). When drilling to 5 mm without irrigation, drill material influenced mean temperature; when drilling to 13 mm without irrigation, the greatest ΔT (5.5°C) occurred in EG. The highest temperature was observed in SG (79.6°C). After 50 uses, the greatest ΔT occurred in EG and the ∅3.0-mm drill exhibited the highest mean and peak temperatures. Temperatures were influenced by irrigation, number of uses, depth, drill diameter, geometry, and material; however, mean values were within physiological limits.

容器，内装建材向け表面処理鋼板のクロメートフリー化の状況

容器，内装建材向け表面処理鋼板のクロメートフリー化の状況

A sulfuric acid surface treatment of mild steel for enhancing the protective properties of an organosilane coating

Abstract This work intends to study the effect of mild steel treatment with sulfuric acid solutions on the protective properties of subsequent organosilane coating. For this purpose, acid solutions were prepared at different pHs including 1.5, 3, 4 and 5. FE-SEM, AFM, XPS and water contact angle measurements was used to investigate the surface chemistry and morphology changes on the mild steel after acid treatments. EIS was employed to evaluate the electrochemical properties of organosilane coatings on mild steel treated by the acid solutions. The results showed that the optimal surface treatment was obtained at pH 3.

Electron beam surface treatment of tool steels

In this work we present a combined method for surface modification on tool steel (0,31%C; 0,30%Si; 0,35%Mn; 2,9%Cr; 2,8%Mo; 0,5%V), consisting of electron beam treatment, plasma nitriding and subsequent electron beam treatment. The electron beam treatment has been performed on a Leybold Heraus (ESW300 - 15/60) installation, and the plasma nitriding – on an installation of the type ION 500. The structure of the processed samples has been investigated by X-ray diffraction analysis and scanning electron microscopy. The microhardness measuring is carried out by means of device MicroDuromat 4000 of firm Reichert-Jung. The results obtained in this study show the formation of Fe3N and FeN0.076 phases after EBT+PN and EBT+PN+EBT respectively. The transformation from Fe3N to FeN0.076 is due redistribution of the nitrogen atoms. The metallographic analysis demonstrates a formation of gradient layers with superior mechanical properties. The measured hardness reaches a value of 718 kg/mm2 for the case of EBT+PN and 679 kg/mm2 after EBT+PN+EBT treatment respectively.

Modeling the Corrosion Inhibition of Mild Steel in HCl Medium with the Inhibitor of Pawpaw Leaves Extract

Modeling the corrosion inhibition of mild steel in HCl medium with inhibitor of pawpaw leaves extract is presented. The extract was analyzed using gas chromatography - mass spectrometry . Thermometric and gravimetric methods were employed in the corrosion inhibition study. The inhibition efficiency w as modeled and optimized using response surface methodology (RSM) . It was observed that the free energy of adsorption ( ∆ G ads ) was negative and less than the threshold value of - 40 kJ/mol . T he adsorption of the extract was spontaneous , and occurred according to the mechanism of physical adsorption . A quadratic model was generated, with optimum i nhibition efficiency of 80.29 % obtained. The extract was highly efficient in the corrosion control process . It is effective for surface treatment of mild steel in the acid medium. Therefore, i t is recommended that pawpaw leaves extract should be employed as corrosion inhibitor in oil well acidizing and surface treatment of mild steel .

Nanostructured vanadium-based conversion treatment of mild steel substrate: formation process via noise measurement, surface analysis and anti-corrosion behavior

The bath pH, vanadia solution concentration and immersion time were optimized for the chemical surface treatment of ST12 mild steel by vanadium-based conversion coating (VCC). Nano-sized vanadium oxide/hydroxide particles were found to form on the steel surface.

Surface Treatments of Stainless Steel by Electroless Silver Coatings as a Bipolar Plate for Proton Exchange Membrane Fuel Cells

The objective of this study is to examine the effect of heat treatment at various temperatures on the corrosion behavior of electroless silver-coated SS 304 in a simulated proton exchange membrane (PEM) fuel cell environment. The corrosion properties of this material were studied using a potentiodynamic polarization technique. X-ray diffraction (XRD) patterns, polarization curves, and scanning electron microscopy (SEM) of coated and heat-treated specimens obtained in various heating temperatures were also utilized. It was found that the corrosion potential of the coated and heat-treated specimens shift toward a noble potential, and a significant decrease in corrosion current density was also observed. The corrosion current density decreased by a factor of about 1/500 for the heat-treated sample of 600 °C compared to the substrate. The heat-treated specimens displayed greater corrosion resistance than unheated and bare ones. According to the polarization studies and SEM images, the heat-treated specimen at 600 °C shows excellent corrosion resistance with a homogeneous dense surface morphology. These results demonstrated the coatings were suited for fuel cell applications in the proton exchange membrane fuel cell (PEMFC) environment.

Duplex surface treatment of steels by nitriding and chromizing

Duplex surface treatment, that is, chromizing and plasma nitriding (PN) of steels have attracted interest from industrial sectors because of its attractive properties and ability to apply on different types of steels. This paper aims to investigate duplex treatment on different types of steels at different treatment conditions. The improvements of the treated surfaces in terms of morphology and thickness, composition, surface hardness and roughness, as well as wear and friction of the engineered layer have been analysed. It was found that several layers of different thickness are formed due to duplex treatment which depends on the specimen’s carbon content and treatment temperature. Mainly carbides and nitrides of chromium and iron are formed, where the amount and composition of them are controlled by duplex treatment process parameters. These compounds enhance the hardness and wear resistance of the treated surface. The CrxN phase is the main contributor towards high microhardness of duplex-treated layers. In addition to high hardness, it also provides excellent wear resistance properties. The PN process reduces the coefficient of friction of chromized steels due to the lower friction coefficient of chromium nitride. However, the surface roughness of the treated surface increases due to the intrinsic properties of formed phases.

Laser Surface Treatment of Hydro and Thermal Power Plant Components and Their Coatings: A Review and Recent Findings

High-power diode laser (HPDL) surface modification of hydro and thermal power plant components is of the utmost importance to minimize their damages occurring due to cavitation erosion, water droplet erosion, and particle erosion (CE, WDE, and PE). Special emphasis is given on the HPDL surface treatment of martensitic and precipitate-hardened stainless steels, Ti6Al4V alloy, plasma ion nitro-carburized layers, high pressure high velocity oxy-fuel and twin-wire arc sprayed coatings. WDE test results of all these materials and coatings in ‘untreated’ and ‘HPDL- treated at 1550 °C’ conditions, up to 8.55 million cycles, are already available. Their WDE testing was further continued up to 10.43 million cycles. The X20Cr13 and X10CrNiMoV1222, the most common martensitic stainless steels used in hydro and thermal power plants, were HPDL surface treated at higher temperature (1650 °C) and their WDE test results were also obtained up to 10.43 million cycles. It is observed that the increased HPDL surface temperature from 1550 to 1650 °C has resulted in significant improvement in their WDE resistances because of increased martensitic (ά) phase at higher temperature. After conducting long-range WDE tests, the correlation of CE, WDE, and PE resistances of these materials and protective coatings with their mechanical properties such as fracture toughness and microhardness product, ultimate resilience, modified resilience, and ultimate modified resilience has been reviewed and discussed. One of the edges of a 500 MW low pressure steam turbine moving blade (X10CrNiMoV1222 stainless steel) was HPDL surface treated at 1550 °C and its radii of curvatures and deflections were measured. These were compared with the data available earlier from a flat rectangular sample of similar composition and identical HPDL surface temperature.

Surface Modification of 316 L Stainless Steel by Sol-Gel Ceramic Coating and its Cytocompatibility

In this research, sol-gel method was utilized to prepare ceramic coating on medical grade 316 L stainless steel with different annealing temperature, solution constitute and coating layers. As-prepared zirconia film morphology was characterized by scanning electron microscope. The human umbilical vein endothelial cells (HUVECs) were cultured on specimens to evaluate their biocompatibility, with fluorescence staining to observe the morphology of cells. The results showed that annealed zirconia film was improved mechanical properties. According to the bio-evaluation results, HUVECs shows very small difference on proliferation activity on ZrO2 coatings compared to 316 L stainless steel, which was shows high difference on proinflammation response test. This indicated that ceramic coating can be indeed less aggressive, which was use for potential future application in surface treatment of stainless steel in scalpels and indwelling needle.

Friction and wear properties of black oxide surfaces in rolling/sliding contacts

Black oxide chemical conversion treatment of steel surfaces was originally developed as a low-cost method to improve the corrosion resistance of the base material. Over time, this surface treatment was introduced on tribological components amid claims that it improved galling and smearing resistance. In rolling element bearings, smearing damage can occur during high transient slip events between roller bodies and raceways, and black oxide surface treatments have recently been prescribed as a solution for this mode of adhesive wear damage. Therefore, fundamental friction and wear experiments using unidirectional sliding and rolling/sliding contacts were conducted to explore the performance of black oxide surfaces in tribological contacts.From this work, it was concluded that mated black oxide surfaces yield similar or lower friction as compared to mated steel surfaces (in lubricated contacts), exhibit high wear in low λ conditions, and can mitigate adhesive wear damage as long as the oxide layer remains intact.

Investigation of stress-strained state of complex parts after plasma surface hardening

The structure and properties of 35CML steel after plasma hardening was investigated, the mechanisms of influence upon formation of phase composition and residual stresses after surface treatment were revealed. It was found out that that residual micro-stresses at surface treatment of steel represented an algebraic sum of strain of two kinds – thermal strain, caused by uneven distribution of temperature along the part’s cross-section and structural strains, due to changes in volume resulting from phase transitions. Residual stresses in the surface layer were determined experimentally. Distribution of deformations in the specified part was simulated by applying of a source of highly concentrated energy. Recommendations were offered for the choice of the modes of plasma treatment. A part, made of the specified steel was hardened with application of designated modes and its geometric shape was controlled. Plasma surface treatment proved to be a promising method of increasing durability of engineering parts.