JournalTOCs API - articles

Use of corrosion-resistant steels and alloys in sulfuric acid media

A. S. Zholud A. S. Derbyshev ; Yu. N. Dulepov — Thu, 02 Feb 2012 17:57:56 GMT

Use of corrosion-resistant steels and alloys in sulfuric acid media
A. S. Zholud A. S. Derbyshev ; Yu. N. Dulepov
Chemical and Petroleum Engineering, Vol. , No. (2012) pp. 627 - 631
Within the chemical industry, and also in some other branches, there is extensive use of sulfuric acid solutions of different concentration and corrosiveness, containing metal ions of varied valency (Cu2+, Fe3+, Ni2+, Cr3+, etc.), which appear in a medium, for example, as a result of equipment corrosion, etc. In sulfuric acid media, corrosion can be uniform or local, i.e., pitting, spot corrosion, intercrystalline corrosion (ICC). Whereas uniform corrosion develops as a gradual reduction in the thickness of an original vessel, equipment, and machine component elements, whose corrosion rate may be calculated previously from existing data for the corrosion resistance of structural materials in specific production media, it is almost impossible to predict ICC development, and therefore in many cases it leads to sudden structural breakdown. In order to predict corrosion, it is recommended to use for article manufacture corrosion-resistant steels and alloys with alloying providing in sulfuric acid solutions resistance to uniform and local corrosion with the required heat treatment and monitoring for ICC resistance.

Specific features of hydrogen-induced corrosion degradation of steels of gas and oil pipelines and oil storage reservoirs

E. I. Kryzhanivs’kyi H. M. Nykyforchyn — Wed, 16 Nov 2011 16:47:48 GMT

Specific features of hydrogen-induced corrosion degradation of steels of gas and oil pipelines and oil storage reservoirs
E. I. Kryzhanivs’kyi H. M. Nykyforchyn
Materials Science, Vol. , No. (2011) pp. 127 - 136
We analyze general regularities of degradation of the mechanical and corrosion-mechanical properties of steels of oil and gas main pipelines and oil storage reservoirs after 28–40 years of operation. The transported oil product not only causes corrosion damages of the internal surface of pipelines and reservoirs, but also becomes a source of hydrogenation of the metal. As a result, it degrades already under the long joint action of mechanical load and hydrogen. Changes in (degradation of) the mechanical properties of the sections of a pipe or a reservoir that contact with the transported medium during operation indicate this fact. First of all, this manifests itself as embrittlement of the metal, i.e., as decreases in the plasticity and resistance to fracture. Comparison assessment of operated and nonoperated steels showed the high sensitivity of the electrochemical properties to the state of the metal, which offers prospects for the development of electrochemical methods for assessing its in-service degradation.

Correlation of the corrosion rates of steels in a straw fired boiler with the thermodynamically predicted trend of KOH(g) in the flue gases

2012-02-03T23:22:14Z

Correlation of the corrosion rates of steels in a straw fired boiler with the thermodynamically predicted trend of KOH(g) in the flue gases

Biomass and Bioenergy, Vol. , No. (2012) pp. -
Publication year: 2012 Source: Biomass and Bioenergy, Available online 1 February 2012 Tom Blomberg The thermodynamic stability of KOH(g) in flue gases without sulfur and chlorine compounds was studied. Relatively good correlation of the thermodynamically predicted trend of KOH(g) in the flue gases and the literature data of the corrosion rates of different steels in a straw fired boiler was found. A discussion on a possible, physically reasonable mechanism is also presented. However, the causality of the found correlation requires further studies. Highlights► Corrosion rates in a straw boiler correlate with the predicted trend of KOH(g). ► KOH(g) impinging the surface may be an important factor in corrosion in straw fired boilers. ► The proposed mechanism may be relevant also to other biomass fuels that release potassium hydroxide during combustion.

Corrosion properties of S-phase layers formed on medical grade austenitic stainless steel

Joseph Buhagiar Hanshan Dong — Mon, 12 Dec 2011 17:13:11 GMT

Corrosion properties of S-phase layers formed on medical grade austenitic stainless steel
Joseph Buhagiar Hanshan Dong
Journal of Materials Science: Materials in Medicine, Vol. , No. (2011) pp. 1 - 11
Abstract The corrosion properties of S-phase surface layers formed in AISI 316LVM (ASTM F138) and High-N (ASTM F1586) medical grade austenitic stainless steels by plasma surface alloying with nitrogen (at 430°C), carbon (at 500°C) and both carbon and nitrogen (at 430°C) has been investigated. The corrosion behaviour of the S-phase layers in Ringer’s solutions was evaluated using potentiodynamic and immersion corrosion tests. The corrosion damage was evaluated using microscopy, hardness testing, inductive coupled plasma mass spectroscopy and X-ray diffraction. The experimental results have demonstrated that low-temperature nitriding, carburising and carbonitriding can improve the localised corrosion resistance of both industrial and medical grade austenitic stainless steels as long as the threshold sensitisation temperature is not reached. Carburising at 500°C has proved to be the best hardening treatment with the least effect on the corrosion resistance of the parent alloy.

Corrosion properties of S-phase layers formed on medical grade austenitic stainless steel

Joseph Buhagiar Hanshan Dong — Mon, 12 Dec 2011 17:13:11 GMT

Corrosion properties of S-phase layers formed on medical grade austenitic stainless steel
Joseph Buhagiar Hanshan Dong
Journal of Materials Science Materials in Medicine, Vol. , No. (2011) pp. 1 - 11
Abstract The corrosion properties of S-phase surface layers formed in AISI 316LVM (ASTM F138) and High-N (ASTM F1586) medical grade austenitic stainless steels by plasma surface alloying with nitrogen (at 430°C), carbon (at 500°C) and both carbon and nitrogen (at 430°C) has been investigated. The corrosion behaviour of the S-phase layers in Ringer’s solutions was evaluated using potentiodynamic and immersion corrosion tests. The corrosion damage was evaluated using microscopy, hardness testing, inductive coupled plasma mass spectroscopy and X-ray diffraction. The experimental results have demonstrated that low-temperature nitriding, carburising and carbonitriding can improve the localised corrosion resistance of both industrial and medical grade austenitic stainless steels as long as the threshold sensitisation temperature is not reached. Carburising at 500°C has proved to be the best hardening treatment with the least effect on the corrosion resistance of the parent alloy.

Fretting corrosion in liquid lead of structural steels for lead-cooled nuclear systems. Preliminary study of the influence of temperature and time

M. Del Giacco, A. Weisenburger, G. Mueller — 2012-01-27T22:09:53Z

Fretting corrosion in liquid lead of structural steels for lead-cooled nuclear systems. Preliminary study of the influence of temperature and time

Journal of Nuclear Materials, Vol. , No. (2012) pp. -
Publication year: 2012 Source: Journal of Nuclear Materials, Available online 25 January 2012 M. Del Giacco, A. Weisenburger, G. Mueller Structural materials development is a key issue for the realization of advanced lead cooled nuclear systems. One specific challenge for fuel claddings and heat exchanger tubes is the so called fretting corrosion by flow induced vibrations. To address this matter, the ferritic-martensitic steel T91and the austenitic steel 1.4970 were submitted to fretting corrosion test in liquid lead. Preliminary indications concerning the role of temperature and time/number of cycles in the fretting corrosion process, were achieved performing fretting corrosion tests at 450 / 500 °C and for 150 / 600 h (5.4·10/ 2.16·10cycles). The interaction between fretting (mechanical wear) and corrosion processes (oxidation/dissolution) in liquid lead was also investigated.The experiments revealed that protective oxide scales that formed on steels surfaces are removed by the fretting action. Thus, dissolution attack can take place. Besides, in the fretted areas, the formation of interposing layers was noticed. Such scales, created by debris retention and compaction, consist of an outer layer of oxidized debris and an inner layer of metallic debris. Due to the high Ni content, fretting corrosion affects more significantly the 1.4970 than the T91. Moreover after the 600 h test, fatigue cracking was observed on the 1.4970. The volume of material removed from the specimens by fretting corrosion, increased with temperature and time respectively number of cycles.

TBM testing in ITER: Requirements for the development of predictive tools to describe corrosion-related phenomena in HCLL blankets towards DEMO

2011-12-14T22:14:57Z

TBM testing in ITER: Requirements for the development of predictive tools to describe corrosion-related phenomena in HCLL blankets towards DEMO

Fusion Engineering and Design, Vol. , No. (2011) pp. -
Publication year: 2011 Source: Fusion Engineering and Design, Available online 14 December 2011 W. Krauss, J. Konys, A. Li-Puma Compatibility testing of RAFM-steels in Pb–15.7Li environment has shown that liquid metal corrosion is always present and dissolution of steel elements in hot areas of non-isothermal systems takes place whereas a transport of the corrosion products and formed precipitates has to be considered in the TBM design.It is clear that for the design of a HCLL breeding blanket system for DEMO and to ensure the safety over a fusion power plant lifetime, a good knowledge of the corrosion behavior including the dominating mechanisms is required. Simulation tools predicting the corrosion behavior of bare and coated Eurofer in Pb–15.7Li must be implemented and validated in a real fusion environment where numerous physical phenomena are additionally present, compared to the state of the art corrosion knowledge, such as neutron flux, H, T permeation, MHD effects, temperature field with steep gradients.The state of the art will be shown and discussed using some of the main fundamental corrosion data selected from own testing campaigns and published literature regarding corrosion behavior of TBMs.On this basis a test matrix for TBM testing in ITER is presented in the paper and the deficits in present knowledge are outlined deviating future development needs in corrosion. Highlights► To collect corrosion data relevant for TBM operation in updated facilities. ► To develop predictive tools (corrosion, transport, precipitation, impurity effects). ► To perform validation of predictive tools. ► To develop/qualify components for TBM tests in ITER.

Grit blasting of medical stainless steel: implications on its corrosion behavior, ion release and biocompatibility

Tue, 24 Jan 2012 06:55:00 GMT

Grit blasting of medical stainless steel: implications on its corrosion behavior, ion release and biocompatibility
J. C. Galván L. Saldaña ; M. Multigner ; A. Calzado-Martín ; M. Larrea ; C. Serra ; N. Vilaboa ; J. L. González-Carrasco
Journal of Materials Science Materials in Medicine, Vol. , No. (2012) pp. 1 - 10
Abstract This study reports on the biocompatibility of 316 LVM steel blasted with small and rounded ZrO2 particles or larger and angular shaped Al2O3 particles. The effect of blasting on the in vitro corrosion behavior and the associated ion release is also considered. Surface of Al2O3 blasted samples was rougher than that of ZrO2 blasted samples, which was also manifested by a higher surface area. Compared to the polished alloy, blasted steels exhibited a lower corrosion resistance at the earlier stages of immersion, particularly when using Al2O3 particles. With increasing immersion time, blasted samples experienced an improvement of the corrosion resistance, achieving impedance values typical of passive alloys. Blasting of the alloy led to an increase in Fe release and the leaching of Ni, Mn, Cr and Mo. On all surfaces, ion release is higher during the first 24 h exposure and tends to decrease during the subsequent exposure time. Despite the lower corrosion resistance and higher amount of ions released, blasted alloys exhibit a good biocompatibility, as demonstrated by culturing osteoblastic cells that attached and grew on the surfaces.

Grit blasting of medical stainless steel: implications on its corrosion behavior, ion release and biocompatibility

Tue, 24 Jan 2012 06:55:00 GMT

Grit blasting of medical stainless steel: implications on its corrosion behavior, ion release and biocompatibility
J. C. Galván L. Saldaña ; M. Multigner ; A. Calzado-Martín ; M. Larrea ; C. Serra ; N. Vilaboa ; J. L. González-Carrasco
Journal of Materials Science: Materials in Medicine, Vol. , No. (2012) pp. 1 - 10
Abstract This study reports on the biocompatibility of 316 LVM steel blasted with small and rounded ZrO2 particles or larger and angular shaped Al2O3 particles. The effect of blasting on the in vitro corrosion behavior and the associated ion release is also considered. Surface of Al2O3 blasted samples was rougher than that of ZrO2 blasted samples, which was also manifested by a higher surface area. Compared to the polished alloy, blasted steels exhibited a lower corrosion resistance at the earlier stages of immersion, particularly when using Al2O3 particles. With increasing immersion time, blasted samples experienced an improvement of the corrosion resistance, achieving impedance values typical of passive alloys. Blasting of the alloy led to an increase in Fe release and the leaching of Ni, Mn, Cr and Mo. On all surfaces, ion release is higher during the first 24 h exposure and tends to decrease during the subsequent exposure time. Despite the lower corrosion resistance and higher amount of ions released, blasted alloys exhibit a good biocompatibility, as demonstrated by culturing osteoblastic cells that attached and grew on the surfaces.

Corrosion of materials in hydrochloric acid solutions

A. S. Derbyshev A. N. Suriev ; A. N. Efimov ; I. A. Beresneva ; F. A. Ladygin — Thu, 02 Feb 2012 17:57:57 GMT

Corrosion of materials in hydrochloric acid solutions
A. S. Derbyshev A. N. Suriev ; A. N. Efimov ; I. A. Beresneva ; F. A. Ladygin
Chemical and Petroleum Engineering, Vol. , No. (2012) pp. 632 - 634
Hydrochloric acid solutions, particularly at elevated temperature, are very corrosive media and cause rapid corrosion of the majority of metals, steels, and alloys, and also chemical breakdown of many nonmetallic materials. Under laboratory conditions in 2% hydrochloric acid solution at 20–25°C the corrosion resistance is studied for specimens of steels 12Kh18N10T, 10Kh17N13M3T, alloy 06KhN28MDT, and titanium VT1-0, and also in 20% hydrochloric acid solution at 95–100°C for specimens of nickel-molybdenum alloys N70MFV-VI (EP814A-VI), alloy N65M-VI (EP982), titanium-palladium alloy 4200 (Ti–0.2%Pd), zirconium, and tantalum, as well as nonmetallic materials, i.e., fluoroplastic, glass, porcelain, faolite, graphite, polypropylene, cross-linked polyethylene, acrylic plastic, silicon carbide composite, and vinyl plastic. The test duration is 1000 h. In 2% hydrochloric acid solution at 20–25°C high resistance is exhibited by titanium VT1-0, alloy 06KhN28MDT, and corrosion-resistant chromium-nickel-molybdenum alloy 10Kh17N13M3T, from which it is possible to manufacture equipment and engineering pipelines in contact with low-concentration hydrochloric acid solutions operating at ambient temperature. In hydrochloric acid solution with a weight concentration of 20% at 95–100°C high resistance to uniform and local corrosion is exhibited by zirconium and tantalum, and the rate of corrosion penetration for alloy N70MFV-VI (EP814A) is 0.447 mm/yr, for alloy KhN63MB it is 1.441 mm/yr, for alloy KhN65MV it is 13.931 mm/yr, and for alloy 4200 it is 3.403 mm/yr. Of the nonmetallic materials, alongside fluoroplastic, high chemical resistance is exhibited by polypropylene, and cross-linked polyethylene.

Corrosion of ZrO2treated type 304 stainless steels in high temperature pure water with various amounts of hydrogen peroxide

2011-12-30T02:45:30Z

Corrosion of ZrO2treated type 304 stainless steels in high temperature pure water with various amounts of hydrogen peroxide

Progress in Nuclear Energy, Vol. , No. (2011) pp. -
Publication year: 2011 Source: Progress in Nuclear Energy, Available online 28 December 2011 Tsung-Kuang Yeh, Po-I. Wu, Chuen- Horng Tsai As boiling water reactors (BWRs) age, intergranular stress corrosion cracking (IGSCC) of the structural materials in the reactor piping systems and vessel internals has become a major degradation problem. Several approaches to mitigating IGSCC in the structural components have been developed and investigated. Among them, the technique of inhibitive protective coatings is deemed the most promising one since it is expected to work even in the absence of the well-known hydrogen water chemistry technology.Following our earlier work on exploring the electrochemical characteristics of important oxidizing species on zirconium oxide (ZrO2) treated Type 304 stainless steels (SSs), we targeted on the characteristics of hydrogen peroxide, which is another strongly oxidizing species in the reactor coolant other than oxygen, in this study. Tests were conducted to determine electrochemical parameters such as electrochemical corrosion potential (ECP), corrosion current density, exchange current density and Tafel constant of the reduction reaction of hydrogen peroxide on 304 SS specimens before and after the ZrO2treatment. The surface morphologies of the treated and untreated specimens were examined by scanning electron microscopy, energy dispersive X-ray spectroscopy, and laser Raman spectra. Furthermore, the corrosion mitigation efficiency of ZrO2treatment was evaluated by electrochemical polarization tests in simulated BWR environments. Test results showed that there were no significant differences in ECP between the untreated and ZrO2treated specimens in the test environments of various hydrogen peroxide concentrations. However, it was found via polarization analysis that the exchange current density of the reduction reaction on and the corrosion current density of the treated specimens were markedly lower than those on and of the untreated ones in the same environments. The ZrO2treatment was able to deter the reduction rate of hydrogen peroxide on the Type 304 SS surface.

Revisiting Stress Corrosion Cracking of Steel in Caustic Solutions for Developing Cracking Susceptibility Diagrams for Improved Applicability

Sarvesh Pal R. K. Singh Raman ; R. N. Ibrahim — Fri, 27 Jan 2012 06:51:47 GMT

Revisiting Stress Corrosion Cracking of Steel in Caustic Solutions for Developing Cracking Susceptibility Diagrams for Improved Applicability
Sarvesh Pal R. K. Singh Raman ; R. N. Ibrahim
Metallurgical and Materials Transactions A, Vol. , No. (2012) pp. 1 - 12
Abstract Stress corrosion cracking tests were conducted using Bayer solutions of different chemistry at different temperatures for extraction of alumina from bauxite ores. The validity of the commonly used caustic cracking susceptibility (CS) diagram for steels exposed to plain caustic solutions was assessed by testing the notched and precracked specimens. This study presents first results toward the development of a model susceptibility diagram for actual Bayer solutions, and for improved applicability of the traditional plain caustic diagram. For mechanistic understanding of caustic cracking, tests were also carried out under imposed electrochemical conditions.

Sensitization and Intergranular Corrosion Behavior of High Nitrogen Type 304LN Stainless Steels for Reprocessing and Waste Management Applications

Thu, 19 Jan 2012 06:45:51 GMT

Sensitization and Intergranular Corrosion Behavior of High Nitrogen Type 304LN Stainless Steels for Reprocessing and Waste Management Applications
N. Parvathavarthini U. Kamachi Mudali ; Lilyana Nenova ; Chavdar Andreev ; Baldev Raj
Metallurgical and Materials Transactions A, Vol. , No. (2012) pp. 1 - 16
Abstract High nitrogen 304LN stainless steels (SS) intended for chloride and nitric acid environments in spent nuclear fuel reprocessing and waste management applications were evaluated for their sensitization and intergranular corrosion (IGC) resistance. For this purpose, high nitrogen (0.132 pct, 0.193 pct and 0.406 pct) containing, impurity-controlled, vanadium-added 304LN SS alloys were developed. For comparison, 304L SS, which is currently used in reprocessing plants, was also studied. These stainless steels were subjected to heat treatment at 948 K (675 °C) for various durations ranging from 1 to 1000 hours and tested for susceptibility to IGC as per ASTM A262 Practice A and E tests. The degree of sensitization was estimated with the double loop electrochemical potentiokinetic reactivation technique. The increase in nitrogen content resulted in higher hardness and finer grain size. Based on the detailed microstructural and corrosion studies, it was determined that an addition of 0.132 pct and 0.193 pct nitrogen showed better IGC resistance and an additional increase in nitrogen resulted in deterioration resulting from chromium nitride precipitation, which was confirmed by electrochemical phase separation and X-ray diffraction studies. The onset of desensitization was faster for the alloy with 0.132 pct nitrogen as well as 0.406 pct nitrogen because of the lower nitrogen content in the former case and the finer grain size in the latter case. The higher hardness and superior IGC resistance of 0.132 pct and 0.193 pct nitrogen containing Type 304LN SS suggests the suitability of this alloy for nitric acid- and chloride-containing environments of reprocessing and waste management plants.

Influence of steel shim hardness on the Sliding Hinge Joint performance

2011-12-14T22:09:43Z

Influence of steel shim hardness on the Sliding Hinge Joint performance

Journal of Constructional Steel Research, Vol. , No. (2011) pp. -
Publication year: 2011 Source: Journal of Constructional Steel Research, Available online 14 December 2011 Hsen-Han Khoo, Charles Clifton, John Butterworth, Gregory MacRae, George Ferguson The Sliding Hinge Joint is a flexural connection designed for use at the ends of beams in steel moment resisting frames. It is an asymmetric friction connection, where energy is dissipated through sliding in slotted bolted connections in the beam bottom flange. The friction resistance and the repeatability of the hysteretic force displacement curves are dependent on the type of shim used. Brass or mild steel shims have been researched and used in construction to date. This paper describes tests on the sliding components conducted to investigate the use of steel shims of different hardness. The materials tested were mild steel, high strength quenched and tempered steel, and abrasion resistant steel. The beam and cleats which these shims slid against were Grade 300 mild steel. The specimens were tested dynamically at earthquake rates of loading. The abrasion resistant steel, the hardest material, produced the most stable and consistent sliding characteristics for all displacement cycles on different specimens. It also had the least material wear and the highest friction capacity per bolt. Compared to brass, high strength steels are more readily available, less costly, more easily erected, and less susceptible to corrosion, making them a preferred solution. Highlights► Asymmetric friction connections tested dynamically with different shims. ► Shims were of different steel grade and hardness, sliding on mild steel. ► Performance was evaluated based on material wear and sliding characteristics. ► Abrasion resistant steel, the hardest shim tested, performed the best. ► Abrasion resistant steel had least wear, most stable and highest sliding friction.

Comparison between symmetric and asymmetric hot rolling techniques performed on duplex stainless steel 2205

C. Mapelli S. Barella ; D. Mombelli ; C. Baldizzone ; A. Gruttadauria — Wed, 11 Jan 2012 17:57:27 GMT

Comparison between symmetric and asymmetric hot rolling techniques performed on duplex stainless steel 2205
C. Mapelli S. Barella ; D. Mombelli ; C. Baldizzone ; A. Gruttadauria
International Journal of Material Forming, Vol. , No. (2012) pp. 1 - 13
Abstract The use of duplex stainless steel represents one possible efficient alternative of austenitic grade and an interesting resources for its high performance against stress corrosion cracking. Unfortunately such material shows some limitations in their use: for instance the sheets or plates of duplex stainless steels present anomalous and poor formability for plastic deformation processes. Such problems are mainly related to an unsuitable normal anisotropy coefficient, which might cause the “necking” and “earing” phenomena, especially during hot rolling. The study deals with the comparison of symmetric and asymmetric rolling technique on stainless steel duplex 2205 specimens. All the experiments were carried out using a laboratory mill, properly equipped with an individual engine for each rolling cylinder. The experimental parameters considered include three different pre-heating temperatures and two asymmetry ratios, while the reduction level is maintained constant for both rolling configurations. Moreover, the study involves also the analysis of the influence of solubilization quenching and the SEM, SEM-EBSD investigation dedicated to establish the microstructure modifications. The specimens were also studied through tensile tests to determine the influence of the rolling techniques on the mechanical properties of the product, focusing on the definition of the average anisotropy coefficient. The results of the experimental trials allow to conclude that the use of asymmetric rolling process induces an improved formability and increases duplex 2205 tensile properties.