Stainless Steel In Water Research Articles

Correction to: New water-stainless steel rod-plate heat pipe: model and experiments

Correction to: New water-stainless steel rod-plate heat pipe: model and experiments

New water-stainless steel rod-plate heat pipe: model and experiments

New water-stainless steel rod-plate heat pipe: model and experiments

Molten drop oxidation of zirconium mixed with stainless steel in water

Molten drop oxidation of zirconium mixed with stainless steel in water

Ultrafast Laser Texturing of Stainless Steel in Water and Air Environment

Ultrafast laser texturing allows the generation of micro- and nanostructures on steel substrates. Laser-ablated textures show a wide range of structure geometries, from the micro to the nanoscale, which can enable plastic product functionalization. Polymer processing technologies are used to replicate mold textures on a large manufacturing scale. To enable new product functionalities, developing novel texture geometries is critical. The laser-ablated texture dimensions are primarily linked to the laser light properties, such as the laser wavelength, thus limiting the achievable structure shapes. This work uses ultrafast laser to manufacture textures in air and water environments. The effect of the different mediums on structures formation is characterized. The irradiation is performed over a wide range of fluence values. The texture geometry and characteristics are evaluated by scanning electron microscopy. For decreasing fluence values, the structures transitioned from micro bumps, to LIPSS, to nanostructures, regardless of the irradiation environment. Conversely, structure morphology is affected by the irradiation environment. The LIPSS pitch is lower for the underwater environment due to the change in the laser angle of incidence, which changes with the refraction index ratio of the air and water. A novel nano-lamellae texture was generated when irradiating the steel surface underwater at relatively low fluence. The dynamics of different LIPSS generations are discussed, considering the irradiation medium’s optical, thermal, and physical properties.

Laser Ablation of Stainless Steel in Water and Hexane: Characterization of Surface Modification and Nanoparticles for Various Applications

This work investigates the effect of a liquid medium on the roughness and the chemical composition of an ablated, stainless steel target, as well as on various properties of the laser-generated nanoparticles, such as absorption, hardness, and yield; in addition, some possible applications of laser ablation in both water and hexane are suggested. It is found that changing the liquid medium from hexane to distilled water not only changes the chemical composition of the target, but also reduces the mass ejected from the target by roughly 25%. Further, this change leads to a “smoother” ablation process and reduces the roughness of the target. Finally, mixed results were obtained when changing the liquid medium. Nanoparticle properties such as yield and absorption were found to be greatly affected, while mechanical properties, such as hardness, are not dependent on the liquid medium.

Oxidation of AISI 304L and 348 Stainless Steels in Water at High Temperatures

Oxidation of AISI 304L and 348 stainless steels was investigated in water at 1000 – 1350 °C by TGA, SEM, EDS, and Raman spectroscopy. Linear-Parabolic kinetics and multilayer oxide scales with voids were found for both alloys. Based on the experimental results, AISI 304L presented higher oxidation resistance and higher activation energy. Zircaloy-4 kinetic results were used for validation and performance comparison. In severe accidents conditions, stainless steel might lead to a faster hydrogen production comparing to Zircaloy.

Fitness-for-service assessment and failure analysis of AISI 304 demineralized-water (DM) pipeline weld crack

Fitness-for-service assessment (FFS) is employed in oil and gas refiners to assess the structural integrity of an in-service pressure vessels and storage tanks that may contain a flaw or damage. API 579/ASME FFS-1 standard provides guidance for conducting FFS assessments using methodologies specifically prepared for pressurized equipment. In the present investigation, FFS assessment (level 3, based on the Failure Assessment Diagram (FAD)) carried out on a 304 demineralized water stainless steel pipeline containing a crack at weldment eleven months before the failure is explained in detail. Despite the FFS assessment and acceptance of the pipeline, failure occurred eleven months after the FFS assessment. The distribution of the residual thermal stress introduced during welding was estimated by means of Finite Element Analysis (FEA) using Abaqus software. Further investigation revealed that the operating condition of the DM pipeline deviated from the date of FFS assessment and the failed pipeline had been under vibration. Defects such as inclusions and porosities and irregular shape of weld bead were observed in weld joint showing lack of proper quality control (QC) during welding and installation of the pipeline. The heat affected zone (HAZ) region was found to be sensitized (perhaps due to the improper welding procedure during installation) and severe precipitation of chromium carbides was observed on the grain boundaries. Further investigation showed the transgranular nature of the crack propagated perpendicular to the weld metal as a result of the dynamic loading caused by steam hammering effect leading to the vibration-induced fatigue. The Scanning Electron Microscopy (SEM) of the fracture surfaces showed that the fracture surfaces consist mostly of fatigue striations and quasi-cleavage fracture.

Nucleation of gas hydrates in multiphase systems with several types of interfaces

Isothermal nucleation of gas hydrates in two-layer water–organic liquid systems was studied with the use of Sapphire Rocking Cell RCS6 with six transparent sapphire cells by thermal analysis under gas pressure. The experiments were conducted at constant supercooling (about 20.2 °C). Decane (both with and without surfactants Surfynol 420 and Span 80) and crude oils were used as organic liquids. It was observed that gas hydrate nucleation occurred at water–stainless steel–gas and water–sapphire–organic liquid three-phase contact lines rather than at water–gas or water–organic liquid interfaces. The empirical survival curves were constructed for the entire set of data. Two series of experiments for the system of water–decane–Surfynol 420–methane with the same sample were also conducted. The series of experiments differed with cell angle relative to the horizontal (45° and 14°). Comparison of the observed thermal effects with data of visual examination for this system allowed nucleation rates of methane hydrate on the different nucleation sites to be determined.

The Effects of Chloride Anions on Corrosion and Passivation Behavior of 254SMO Stainless Steel in Water Absorbed of Blast Furnace Gas (BFG)

The Effects of Chloride Anions on Corrosion and Passivation Behavior of 254SMO Stainless Steel in Water Absorbed of Blast Furnace Gas (BFG)

Vibratory cavitation erosion behavior of AISI 304 stainless steel in water at elevated temperatures

The cavitation erosion behavior of AISI 304 stainless steel was investigated using an ultrasonic vibratory apparatus at elevated temperatures and the morphologies of the eroded surface and the cross section were observed by scanning electron microscopy (SEM) and optical microscopy. The results show that the cumulative mass loss increases, shows a peak and then decreases with increase in liquid temperature. The cavitation damage of the eroded surface was relatively uniform at 20–60°C and at 80°C it was localized; the depth of local deeper pit at 80°C was about 1.7 times deeper than at 50°C. The initial results based on the cumulative mass loss could not predict the degree of cavitation damage, and the depth of local erosion pit may be an effective method for judging erosion damage.

Enhancement on interlaminar shear strength and water-lubricated tribological performance of high-strength glass fabric/phenolic laminate by the incorporation of carbon nanotubes

High-strength glass fabric (HSGF)/phenolic laminates modified with different contents of carbon nanotubes (CNTs) were fabricated by hot-compression technique. The effects of CNTs on the interface of HSGF/phenolic, interlaminar shear strength (ILSS) and water-lubricated tribological performance of HSGF/phenolic laminate were investigated. The ILSS of the laminates were tested on a universal testing machine (DY35), and the tribological properties were evaluated by a block-on-ring tribo-tester. The interfaces of HSGF/phenolic and the worn surfaces of the laminates were analyzed by scanning electron microscope. The results showed that the moderate incorporation of CNTs improved the interface of HSGF/phenolic and accordingly enhanced the ILSS of the laminate. Besides, the friction coefficient of HSGF/phenolic laminate sliding against stainless steel in water can be remarkably stabilized and lowered by the incorporation of CNTs due to the better water lubrication induced by added CNTs and the intrinsic self-lubrication of CNTs which were further graphitized during the friction and wear process. And the wear rate of the laminate can be accordingly reduced by 1 order of magnitude. The results indicate that CNTs have excellent potential in enhancing both ILSS and tribological fabric/polymer laminate composite, which will greatly improve the current situation of deterioration on mechanical properties by adding traditional solid lubricants. Copyright © 2014 John Wiley & Sons, Ltd.

An experimental investigation of underwater pulsed laser forming

Laser forming is a new forming technology, which deforms a metal sheet using laser-induced thermal stresses. This paper presents an experimental investigation of pulsed laser forming of stainless steel in water and air. The effects of cooling conditions on bending angle and morphology of the heat affected zone (HAZ) are studied. It is shown that the case of the top surface in air and the bottom surface immersed in water has the greatest bending angle based on the forming mechanism of TGM. The water layer above the sample decreases the coupling energy, leading to a small bending angle. For a thin water thickness (1mm), the water effects on the HAZ are limited. As water layer thickness increases (5mm), the concave shape of the HAZ is more remarkable and irregular because the shock waves by high laser energy heating water are fully developed. However, the area and the depth of the HAZ become less significant when water thickness is 10mm due to the long pathway that laser undergoes.

Characteristics of Cavitation Erosion Using Image Processing Techniques

This paper deals with the analysis of eroded surfaces obtained from cavitation-erosion experiments on stainless steel in water and oil-in-water (o/w) emulsions using image processing. Two analysis techniques that are very promising in this respect are the wavelet decomposition transform and fractals. These can be used to extract parameters that characterize the cavitation intensity in a similar manner to that of the mean depth of erosion (MDP). The extracted parameters are the wavelet energy and entropy as well as the fractal dimension. Both of the image feature parameters and the MDP decrease with adding oil to water. Also, it was found that the variation of image feature parameters versus concentration of oil-in-water emulsions has a general trend that does not depend on magnification factor. The cavitation erosion behavior and mechanism for water and o/w emulsions were analyzed and it was found that the predominant failure mode was fatigue for water and o/w emulsions. The results show that a corrosive effect appears at 5 and 10 wt% o/w emulsions.

Influence of glyoxal on localized corrosion of austenitic stainless steel in spring water

AbstractThis paper presents the research regarding the influence of glyoxal on electrochemical and corrosion behaviour of austenitic stainless steel in water. For this purpose, model solutions containing glyoxal in water in concentrations ranging from 0.1 to 1 % were prepared. Spring water was used as control electrolyte. From the potentiostatic polarisation data (using the standard three‐electrode system), the corrosion current (icorr), corrosion potential (Ecorr) and polarisation resistance (Rp) were calculated. The research included also the conductivity, total dissolved soils, salinity, resistivity and pH, absolute potential, and relative potential of model solutions. The presence of glyoxal at the highest concentration of 1 % in the water solution has accelerating effect on corrosion.

Study of an adsorption refrigeration system powered by parabolic trough collector and coupled with a heat pipe

The aim of the current paper is to propose a study of a novel solar adsorptive cooling system, using activated carbon–ammonia pair, coupled with a parabolic trough collector (PTC) and a water-stainless steel heat pipe. A theoretical model, based on the thermodynamics of the adsorption process, heat and mass transfer within the porous medium and energy balance in the hybrid system components, is developed and a simulation code, written in FORTRAN, is carried out. This model, which has been validated by experimentation results, computes the temperature, pressure and adsorbed mass inside the adsorbent bed. The performance is assessed in terms of specific cooling power (SCP) and solar coefficient of performance (COPs). Furthermore, the effect of some important parameters on the system performance is discussed, and an optimization of these parameters is given. The simulation results have shown that there exists, for each aperture width value of the collector ( W), an optimum external radius of adsorbent bed ( R 2). Under the operating and design conditions of evaporation temperature T ev = 0 °C, condensing temperature T con = 28 °C, adsorption temperature T ads = 24 °C, W = 0.70 m, R 2 = 0.145 m and reactor length of 0.5 m, an optimal corresponding COPs is found to be of the order of 0.18.

Study on the stability of plasma-polymerized fluorocarbon ultra-thin coatings on stainless steel in water

Metallic stents are thin wire mesh tubes implanted in partially blocked arteries to prevent the obstruction of blood flow and to act as internal scaffolding. Mainly made of 316L stainless steel, they are prone to localized corrosion attack in long-term applications which in turn causes the release of potentially toxic ions such as chromium and nickel. To improve the long-term performance and safety of stainless steel stents, a multi-step process was previously developed in our laboratory to isolate the stainless steel surface from the body fluid by coating the metal with an ultra-thin cohesive and adherent plasma-polymerized fluoropolymer coating (Teflon-like ultra-thin coating). In this context, the aim of the present study was to evaluate the stability of the Teflon-like ultra-thin coating in deionised (D.I.) water using static immersion tests. Deionised water was selected as ageing medium mainly because it did not contain any compounds that might deposit onto the surface and interfere with further surface analyses. After periods of immersion in D.I. water ranging from 1 to 4 weeks, chemical and morphological characterization of the coating, both in its bulk and surface, was carried out by atomic force microscopy (AFM), ellipsometry, Fourier-transform infrared spectroscopy (FTIR), contact angle measurements (CA) and X-ray photoelectron spectroscopy (XPS). Results have shown that upon ageing, there is a decrease in the fluorine concentration and an oxidation of the coating. The degradation of the coating could probably result from the water, which penetrates the coating and induces changes in the chemical composition and microstructure.

Cavitation wear behaviour of austenitic stainless steels with different grain sizes

The cavitation erosion behaviour of two different austenitic stainless steels in water with different pH values and room temperature have been studied by means of a 20-kHz ultrasonic vibrator operating at a peak-to-peak amplitude of 40 μm. The austenitic stainless steels used were AISI 304 (18Cr–10Ni) steel and a high nitrogen (HN) containing steel. Each of the steels were fabricated to yield three different grain sizes: 2.5 μm, 20 μm and 45 μm. The grain size in both steels was adjusted by inducing an austenite–martensite–austenite phase transformation. Grain refining results in an improvement of the mechanical properties: hardness, yield strength, tensile strength, fatigue strength as well as an enhancement in the corrosion resistance. The grain size of the steels has an important effect on the nature of damage produced on the surface of the samples. The resistance to cavitation erosion increases continuously with decreasing grain size. It was also found that cavitation erosion resistance of the two steels is sensitive to variations in the pH: a decrease of this value produces an increase in surface damage. This work shows that the HN steel exhibits better cavitation erosion resistance than AISI 304 steel. Also, hardness, tensile strength, yield strength and grain size of both steels can be correlated with the cavitation resistance R e.

Effect of Physical Property and Chemistry of Water on Cracking of Stainless Steels in Sub-Critical and Supercritical Water

It was previously demonstrated by the authors that density of water and the density-related physical properties of water are ones of the major governing factors of corrosion of metals in supercritical aqueous solutions. The water density is expected to have significant effects also on stress corrosion cracking (SCC) of metals in supercritical water. In this study, we have looked into cracking behavior of sensitized and non-sensitized stainless steels in water under various pressures and at fixed temperatures above and below the critical point by using SSRT technique, and discussed its correlation with dielectric constant of water. The experimental results have suggested two different cracking mechanisms of 316(L) stainless steels as follows; For sensitized 316 SS - pure water system; (1) Effects of phase state of water and applied pressure, more essentially, physical property of water, were clearly observed. (2) SCC did not occur in the oxygenated 'gas-like', supercritical water at 400°C/25MPa. (3) Cracking occurred at 400°C/30MPa and the cracking severity was more pronounced as applied pressure was increased up to 60MPa at the same temperature. (4) This variation in cracking susceptibility being dependent on pressure was understood from dielectric constant of water. (5) The results give a strong evidence of the dissolution mechanism. For non-sensitized 316L SS - sulfuric acid water system; (1) Non-sensitized 316L SS severely cracked with IG even in a 'gas-like' supercritical water. (2) Dielectric constant did not affect cracking severity. (3) Cracking was more enhanced at higher temperature. (4) The results suggested oxidation cracking.

Corrosion resistance of common metals and stainless steels in water

Le comportement, vis a vis de la corrosion, des materiaux usuels, comme l'acier, la fonte, l'acier galvanise, depend de la qualite des produits de corrosion protecteurs qui peuvent se former a la surface de ces metaux. La resistance a la corrosion des aciers inoxydables est, elle, tributaire de la perennite de la couche passive qui doit se former, et se maintenir, a la surface en contact avec l'eau. Il suffit pour cela que le milieu soit oxydant, que la teneur en ions chlorure reste dans les limites de la directive CE 98/83 et que les surfaces soient maintenues propres (absence de depots intempestifs). Si ce n'est pas le cas, les problemes de corrosion que l'on peut alors rencontrer sont generalement lies a l'apparition de corrosions localisees, qui peuvent aller jusqu'a la perforation Pour les metaux usuels, les conditions de formation des couches protectrices dependent de parametres plus nombreux. On peut citer: la composition de l'eau, la situation de l'eau vis a vis de l'equilibre calcocarbonique, le pH, les conditions hydrauliques, la nature des circuits, les conditions d'exploitation et d'entretien, etc. L'agent corrosif principal est la plupart du temps l'oxygene dissous. Mais sa presence est paradoxalement necessaire a la mise en place et au maintien des couches protectrices. Cependant, la conception, la realisation, l'exploitation et l'entretien d'un circuit sont des facteurs beaucoup plus importants que la corrosivite propre de l'eau.

Benzotriazole as corrosion inhibitor for type 304 stainless steel in water–ethanol media containing 2M H2SO4

Abstract The effect of benzotriazole (BTAH) as a corrosion inhibitor for type 304 stainless steel in 2M H2SO4 water-ethanol (80: 20) solutions has been studied using weight loss experiments, anodic and cathodic potentiostatic measurements, and analysis by scanning electron microscopy (SEM). BTAH increases the corrosion rate at lower concentrations (≤3·0 × 10−6M) but it provides complete inhibition when [BTAH]≥1·5 × 10−4M. The catalytic effect was also observed from anodic potentiostatic curves for [BTAH] ≤ 10−6M over the entire active potential range. A synergistic effect was observed in the presence of ethanol for higher BTAH concentrations when the system was compared with those in aqueous media. BTAH acts as a cathodic and anodic inhibitor over the entire range of potentials studied.