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CN 21-1264/TQ
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Corrosion Behavior of Nickel-based Alloy 718 at the Simulated H2S/CO2 Environments
As the exploration and development of oil and gas fields continue to deepen, the acidic oil and gas fields are rich in CO2, H2S, Cl- and other corrosive media, which makes the production environment increasingly severe, and puts higher requirements on the performance of the service components.Nickel. . .
Corrosion Science and Protetion Technology, 0 Vol. (): 0-0    DOI: 10.11903/1002.6495.2018.219
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Effect of Temperature on Seawater Corrosion Behavior of X80 Steel Welded Structure PDF (934KB)
Review on the research and development of nuclear radiation-resistant coatings PDF (400KB)
Zhi-qin LI
Preparation of multicomponent heterojunction CdS/PbS/TiO2 and its photocathodic protection performance for 304SS PDF (1267KB)
Study on electrochemical chlorine extraction efficiency of reinforced concrete under different factors PDF (249KB)
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      15 March 2019, Volume 31 Issue 2 Previous Issue    Next Issue
    Survey on Corrosion of Power Transmission and Transformation Equipment
    Xiaojian XIA,Yan JIN,Hanwen QIAO,Xingeng LI,Longwu LEI,Wenkui HAO,Deyuan LIN
    Corrosion Science and Protetion Technology. 2019, 31 (2): 121-127.   DOI: 10.11903/1002.6495.2018.211
    Abstract   HTML   PDF (1079KB)

    A survey on the corrosion issue was made for the power transmission and transformation equipment situated at 27 provinces, autonomous regions and municipalities around the country. The present article summarized the types of metals used in different devices and the total number of corrosion cases of different devices, with emphasis on the cause of corrosion, the corrosion protection methods and its effectiveness. The results indicated that the main cause of corrosion of the power transmission and transformation equipment might be ascribed to the corrosivity of service environments, while the corrosion rate was accelerated due to the inadequacy in equipment design and selection of anti-corrosion methods for the application in highly corrosive environments.

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    Corrosion Behavior of Sherardizing Steel in Different Soils at Four Typical Test Sites
    Jianfei YU,Xuejie ZHOU,Yu ZHANG,Sanping ZHANG,Ming ZHANG
    Corrosion Science and Protetion Technology. 2019, 31 (2): 128-136.   DOI: 10.11903/1002.6495.2018.169
    Abstract   HTML   PDF (38653KB)

    The corrosion of sherardizing steel in soils at four test sites was studied by burying the steel specimens for 2 a. The corrosion morphology of the buried steel specimens was observed by VHX-2000 microscope and the corrosion products were characterized by XRD. Electrochemical test is employed to assess the electrochemical impedance of corrosion products. The results showed that the corrosion rate of the sherardizing steel in the four soils was large. The maximum corrosion rate was detected for the sherardizing steel in the soil of test site at Yingtan district. The property of corrosion products was affected by physical-chemical parameters of soils.

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    Oil-sulfur Induced Corrosion in Bushing and its Effect on Oil-paper Performance
    Guoyong LIU,Yuan YUAN,Xiao REN,Ruijin LIAO,Jiang ZHOU,Youdong JIANG
    Corrosion Science and Protetion Technology. 2019, 31 (2): 137-143.   DOI: 10.11903/1002.6495.2018.192
    Abstract   HTML   PDF (17447KB)

    Corrosion behavior of simulated high voltage bushing models in insulation oil with different concentration of dibenzyl disulfide (DBDS) was assessed at 130 ℃ for 40 d in order to understand the sulfur induced corrosion of Cu core and Al foil in bushings. In addition, corrosion products of Cu core and Al-foil were characterized, while their effect on insulating properties was also discussed. Results show that the corrosion of Cu core and Al foil became severer when corrosion time and the concentration of DBDS increased. The deposited amount of Cu and Al on the insulation paper and oil increased with the increasing time and concentration of DBDS. The dielectric loss and dielectric constant of the insulation paper increased with increasing deposition of Cu2S. The dielectric loss increased and the breakdown voltage decreased with increasing amount of Cu and Al in the insulation oil.

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    Enhancement of Resistance to Sulfur Corrosion for Transformer Copper Windings via Grain Boundary Engineering Technology
    Jiang ZHOU,Yuan YUAN
    Corrosion Science and Protetion Technology. 2019, 31 (2): 144-148.   DOI: 10.11903/1002.6495.2018.193
    Abstract   HTML   PDF (4364KB)

    Faults for transformer occurred often due to the insulation degradation within the transformer, which is always related with the sulfur induced corrosion of copper winding. Therefore, it is meaningful to enhance the corrosion resistance of the transformer Cu-winding via the so called grain boundary engineering (GBE) technology, namely the microstructure of copper winding was adjusted by appropriately cold rolling and annealing of copper winding, therewith its corrosion resistance was improved. Results show that after such treatment the corrosion resistance of winding may be improved significantly. According to the result of comparative corrosion testing in a insulating oil for Cu-widings before and after GBE treatment respectively, it follows that the residual Cu-content in the insulating oil decreases significantly from 3660 μg/kg for the original winding to 2.47 μg/kg for the GBE treated Cu-winding, thus the quality of insulating oil, as far as taking its physical-, chemical- and electrical-properties into consideration, is far much better for the case in the presence of the GBE treated Cu-winding.

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    Research and Application of a Highly Adaptable Anticorrosion Coating for Transmission Tower
    Liang NING,Yun CHEN,Kai YANG,Xianming WANG,Shangui ZHANG
    Corrosion Science and Protetion Technology. 2019, 31 (2): 149-154.   DOI: 10.11903/1002.6495.2018.203
    Abstract   HTML   PDF (3945KB)

    In heavy pollution industrial site, high emissions urban and coastal areas, most of the galvanized pieces are partially or totally corroded. In order to prolong the operating life of transmission equipment in those environments, an anticorrosive coating of high weather resistance and long service life is developed, the coating can prevent corrosive medium from reaching the surface of zinc layer and thus eliminate the occurrence of electrochemical corrosion, the method can solve the corrosion problems of galvanized component in special corrosive environments. In addition, the coating also has good compatibility with rust zinc, rust steel and aged coating etc., therefore, which is an effective means to enhance the safety of power transmission, while reduce the cost of outdoor maintenance.

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    Corrosion Behavior of Pure Copper in Alkaline Soil
    Fengjie YAN,Xingeng LI,Bo JIANG,Zhibin FAN,Sulan TIAN
    Corrosion Science and Protetion Technology. 2019, 31 (2): 155-158.   DOI: 10.11903/1002.6495.2018.173
    Abstract   HTML   PDF (2854KB)

    The corrosion behavior of pure Cu in alkaline soil was studied by accelerated corrosion test and electrochemical test in laboratory, as well as characterization of corrosion products by SEM and XRD. The results showed that a passivation range exists on the potentiodynamic polarization curve for pure Cu in alkaline soil. Homogenous and compact corrosion products are observed on the surface of pure Cu, which consist of CuO, Cu2O and CuSO4·H2O. The corrosion products can isolate the corrosive ions from the substrate metal, therewith inhibit the inward diffusion of oxygen and protect the substrate metal.

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    Corrosion and Peeling off Behavior of Ag Coating on Bushing Wiring Board for 66 kV HGIS in a Coastal Substation
    Tianpeng WANG,Hongqiang LI,Mingcheng SUN,Shaoyang XIAO,Di WU,Yunan WANG,Chao YANG
    Corrosion Science and Protetion Technology. 2019, 31 (2): 159-164.   DOI: 10.11903/1002.6495.2018.164
    Abstract   HTML   PDF (9634KB)

    The corrosion and peeling off behavior of Ag coating on bushing wiring board for 66 kV HGIS in a coastal substation were studied by methods such as macroscopic observation, chemical analysis, metallographic observation and scanning electron microscope (SEM) as well as analysis of the local atmospheric parameters at the region where the substation situated. The result indicated that bubbling and peeling-off emerged in between the Cu-layer and the substrate Al-alloy, whereas the adhesion between the intermediate Cu-layer and the Ag-layer was intact entirely. The bubbled or peeled coating had been oxidized or vulcanized, and the exposed substrate was oxidized. The corrosive media entered the interface between Al-alloy substrate/Ag-layer through scratches on surface or interfacial gaps, which are the main factor causing the corrosion failure of the Al-alloy wiring board.

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    Corrosion Behavior and Corrosion Prevention Measures of Internal Water-cooling Systems for EHV and UHV Converter Valve
    Zhi GENG,Changhua SU,Yongling ZHANG,Jingwei YUAN,Zhigao WANG,Qianqian TIAN,Fangqiang WANG
    Corrosion Science and Protetion Technology. 2019, 31 (2): 165-168.   DOI: 10.11903/1002.6495.2018.170
    Abstract   HTML   PDF (524KB)

    According to the cause of corrosion, the corrosion types emerged in internal cooling systems for extra-high voltage (EHV) and ultra-high voltage (UHV) converter valve may be classified into electrolytic current corrosion, chemical corrosion and physical corrosion. Prevention measures were put forward based on the key factors of different types of corrosion. Ion exchange resin turned out to be an important factor that affect the corrosion of internal cooling systems. In this paper, we introduced our research progress in this factor and the relevant application effect of using appropriate ion exchange resin in several EHVDC and UHVDC converter stations in Sichuan province. For the first time, a novel technical method of ultrafiltration was proposed to completely obstruct the degradation products of ion exchange resin, which would prevent chemical corrosion much effectively. This method presents good prospect in corrosion prevention of water-cooling systems for EHV and UHV converter valve.

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    Comparison of Anticorrosion Measures for Overhead Conductors
    Xu WANG,Guofei HUANG
    Corrosion Science and Protetion Technology. 2019, 31 (2): 169-173.   DOI: 10.11903/1002.6495.2018.166
    Abstract   HTML   PDF (8555KB)

    In order to compare the corrosion resistance of different overhead conductors, neutral salt spray (NSS) test was carried out for the common aluminum conductors steel reinforced (ACSR), aluminum conductors Al-clad steel reinforced (ACSR/AW), greased aluminum conductors steel reinforced (ACSR (greased)) and aluminum conductor composite core reinforced (ACCC). The result shows that: the corrosion of ACSR is the most serious, and for the ACSR/AW, all the inner aluminum wires and the Al-clad steel wires only suffered slightly from corrosion due to that the contact of dissimilar metallic materials is avoided within the strand, i.e. the corrosion resistance of ACSR/AW is much better than the common ACSR. Due to the physical isolation effect of the injected grease, the corrosion of aluminum wires and the steel core of ACSR (greased) is not obvious during the whole test period. For the ACCC, the composite core presents stable chemical properties and excellent corrosion resistance, whilst all the wires of the ACCC are very tightly twisted together, therewith the permeation of corrosive medium inwards to the inner are likely prevented, all the above factors make the corrosion resistance of the ACCC much better than that of the common ACSR.

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    Oxidation Behavior of Type 441 Ferritic Stainless Steel in Synthetic Exhaust Gas
    Yisheng CHEN,Jianming ZHAN,Qingzhao NI,Moucheng LI
    Corrosion Science and Protetion Technology. 2019, 31 (2): 174-180.   DOI: 10.11903/1002.6495.2018.217
    Abstract   HTML   PDF (10441KB)

    The oxidation behavior of type 441 ferritic stainless steel in a synthetic automotive exhaust gas at 900~1050 ℃ was studied by means of mass change measurement, XRD, SEM and EDS. The results indicate that the oxide scale formed at 900 ℃ has a bi-layered structure, i.e., an outer Mn-Cr spinel layer and an inner Cr2O3 layer, while the temperature 900 ℃ is known as the upper service limit for the type 441 ferritic stainless steel in automotive. When the oxidation temperature increases to 950 ℃ and above, oxide nodules appears on the oxide scale. A nodule usually can be differentiated into two parts by the initial formed Mn-Cr spinel layer, Fe-oxides and Fe-Cr oxides mainly form on top of and beneath the spinel thin layer respectively. When the oxidation temperature reaches 1050 ℃, many voids form in the oxide nodules. The growth of oxide nodules leads to breakaway oxidation, therewith, changes the oxidation kinetics from parabolic to linear.

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    Corrosion Mechanism of Typical Water Supply Pipes in a Simulated Coastal Saline Soil Environment
    Yimei TIAN,Chuntong LIU,Hao GUO,Liang PEI
    Corrosion Science and Protetion Technology. 2019, 31 (2): 181-189.   DOI: 10.11903/1002.6495.2018.110
    Abstract   HTML   PDF (3771KB)

    A laboratory accelerated test set-up was built to simulate the environment of the coastal saline soils at Tianjin coastal area. Corrosion performance of three typical materials for water supply pipes such as ductile iron, grey cast iron and carbon steel, was assessed by means of weight loss method and electrochemical measurement. The main conclusions are as follows: the three materials present more or less the same corrosion tendency in the test environment. The corrosion process can be differentiated into three stages: pitting induction stage, pitting developmental stage, and stable corrosion stage. The charge transfer was the control step in the initial- and middle-stage of corrosion, while the charge transfer resistance rose rapidly as the corrosion proceeded, however, the oxygen diffusion became the controlling step for the stable corrosion stage. The polarization curves of three materials showed obvious double control of cathodic diffusion and anodic activation, and the cathode diffusion control was more obvious.

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    Effect of Al-content on High Temperature Oxidation Behavior of Al-containing Austenitic Stainless Steel Fe-22Cr-25Ni
    Yan XIA,Jian WANG,Haojie MENG,Peide HAN
    Corrosion Science and Protetion Technology. 2019, 31 (2): 190-196.   DOI: 10.11903/1002.6495.2018.126
    Abstract   HTML   PDF (12882KB)

    A new alumina-forming austenitic stainless steel with excellent high-temperature oxidation resistance is being widely concerned. In this work, the Al-containing austenitic heat-resistant Fe-25Cr-25Ni steels were prepared by adjusting the Cr- and Ni-content of the present steel HR3C, while adding 1.5% (mass fraction), 2.5% and 3.5%Al respectively. The oxidation behavior of the prepared steels in air at 700, 800 and 900 ℃ respectively was assessed by means of mass change measurement, scanning electron microscopy (SEM) with energy-dispersive spectrum (EDS) and X-ray Diffractometer (XRD). Results show the steels of 22Cr-25Ni-2.5Al and 22Cr-25Ni-3.5Al present excellent oxidation resistance at 700 and 800 ℃ with formation of a continuous and compact Al2O3 protective scale, which hinders the further oxidation of the base metal and improves its high temperature oxidation resistance. However, at 900 ℃ the Al-containing austenitic heat-resistant steels form a scale composed of MnCr2O4 and Cr2O3 with internal oxidation zone composed of oxides and nitrides of Al, which presented not effective protectiveness for the substrate.

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    Effect of Cation Resin Powder on Corrosion Behavior of 6063 Al-Alloy in Valve Cooling System
    Zhouhai QIAN,Yijie CHENG,Xiaoning SONG,Lei YANG,Zhiping ZHU,Zhifeng LIU
    Corrosion Science and Protetion Technology. 2019, 31 (2): 197-204.   DOI: 10.11903/1002.6495.2018.119
    Abstract   HTML   PDF (7857KB)

    Effect of the presence of cation resin powder in coolant waters on the corrosion behavior of 6063 Al-alloy was investigated by immersion test and electrochemical test. Results showed that the presence of either an applied direct current or the cation resin powder could enhance the corrosion of the Al-alloy in the valve cooling system. While, organic sulfonates could enhance the corrosiveness of the solution, so the corrosion rate increased in the early stage of immersion. However, higher concentration of SO42- could inhibit the corrosion of Al-alloy to some extent, resulting in the decrease of corrosion rate in the later stage of immersion, even so, the corrosion rate was still larger. The electrochemical tests showed that in the water with cation resin powder, the corrosion potential of 6063 Al-alloy decreased first and then increased, whilst the corrosion current density increased first and then decreased. In the low frequency region of EIS spectrum, inductive arc appeared and the radii of tolerance arc increased, which indicated that a large amount of SO42- adsorbed on the surface of Al-alloy, in other word, the corrosion of Al-alloy was suppressed to a certain extent. Therefore, in the practical application, the troubles related with corrosion of Al-alloy induced by the cation resin powder to 6063 Al-alloy should be considered and the corresponding countermeasures should be taken for the valve cooling system.

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    Corrosion Inhibition Performance of Valonia Tannin for Q235 Carbon Steel in 0.5 mol/L HCl
    Baohua ZHAO,Hongxin XU,Wenhua ZHANG,Bi SHI
    Corrosion Science and Protetion Technology. 2019, 31 (2): 205-211.   DOI: 10.11903/1002.6495.2018.125
    Abstract   HTML   PDF (8151KB)

    The corrosion inhibition performance of valonia tannin for Q235 carbon steel in 0.5 mol/L HCl solution was investigated by means of mass loss experiment, polarization curve measurement, electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM) as well as molecular simulation. Results showed that in the solution with a dose of 6 g/L valonia tannin, the corrosion inhibition efficiency could reach 96.46%. While the corrosion current of the carbon steel electrode decreased by one order of magnitude and the charge transfer resistance increased up to 7 times of that in the blank solution of 0.5 mol/L HCl. SEM observation revealed that a colorless and compact protective film could form on the steel in the acid solution with the addition of valonia tannin. Valonia tannin was adsorbed on Q235 carbon steel surface through chemisorption and physisorption, which could be well fitted by the Langmuir adsorption isotherm. Furthermore, molecular simulation revealed that the valonia tannin was absorbed as lamelliform lamellae on the surface of carbon steel.

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    Oxidation Behavior of Q235 Carbon Steel in Ethanol Combustion Gas
    Hao HONG,Shuwang DUO,Dongbai XIE
    Corrosion Science and Protetion Technology. 2019, 31 (2): 212-218.   DOI: 10.11903/1002.6495.2018.043
    Abstract   HTML   PDF (7818KB)

    Metallic materials exposed in fire scene environments are usually subjected to severe high temperature oxidation, thus they may usually be utilized as reference to judge the fire environment. In order to reveal the history of burning time and temperature of the fire scene as well as to judge if any combustion accelerant has existed in the scene, the present paper focused on the high temperature oxidation behavior of Q235 carbon steel in a simulated fire environment resulted from combustion of ethanol. Namely, Q235 carbon steel was oxidized for 5, 10, 20 and 30 min in the ethanol flue gas. During the oxidation process, oxidation temperature curve was recorded automatically. The oxidation behavior of Q235 carbon steel in such environment, especially the formation and distribution of carbon on the oxidized steel are examined. The obtained results slow that a mesh-like oxide scale formed on the surface of Q235 carbon steel in the simulated environment, meanwhile, with the increase of oxidation time, the oxide scale twinkled and gradually spalled off. Meanwhile, no FeO was detected in the oxide scale. It was found that free carbon accumulated along the interface of oxide scale/substrate, and the amount of which increased with the increasing time. The fact that FeO did not formed under the experimental conditions may be considered as a criterion for judging the combustion temperature in the practical fire scene. On the other hand, the free carbon caused by pyrolysis of ethanol was deposited on the area with high surface energy, such as the interface of oxide scale/substrate, which would provide a reference for determining the presence of combustion accelerant in the fire scene as well.

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    Corrosion Behavior of Coated P91 Steel and Super304H Steel Beneath NaCl Deposit in High Temperature Water Vapor
    Hong LIU,Guangming LIU,Mingming YU,Wen YANG,Huachun YANG,Xiaohui MAO
    Corrosion Science and Protetion Technology. 2019, 31 (2): 219-224.   DOI: 10.11903/1002.6495.2018.121
    Abstract   HTML   PDF (4769KB)

    Corrosion behavior of P91 steel and Super304H steel was studied beneath a solid NaCl deposit in water vapor containing air at 600 °C. The microstructure and composition of the corrosion products were characterized by XRD, SEM and EDS. Results indicated that both of P91 steel and Super304H steel suffered from disastrous corrosion with significant mass loss. Many cracks and voids were observed in the corrosion product scale, which led to spallation of corrosion products on a large scale. The corrosion product on the surface of P91 steel was mainly composed of Fe2O3. However, the corrosion products of Super304H steel contained (Fe, Cr, Ni)3O4 and NiO. The two steels suffered from serious corrosion may be ascribed to that the protective Cr2O3 oxide scale became not sustainable under the synergistic effect of solid NaCl with water vapor and oxygen at high temperature. Super304H steel with high Cr content suffered from more serious corrosion than that of P91 steel. Meanwhile, obvious intergranular corrosion of Super304H occurred.

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    Effect of Pre-strain Before Aging Treatment on Stress Corrosion Cracking of 2297 Al-Li Alloy
    Yu TIAN,Bo JIANG,Danqing YI,Jun HU,Zehua QIN,Yu XIAO
    Corrosion Science and Protetion Technology. 2019, 31 (2): 225-231.   DOI: 10.11903/1002.6495.2018.073
    Abstract   HTML   PDF (12696KB)

    2297 Al-Li alloy was stretched with varying degrees of deformation and then subjected to peak aging treatment. The influence of pre-strain on the stress corrosion cracking of the aged alloy was studied by means of slow strain rate test (SSRT), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and other methods. Results show that the alloy with 5% pre-strain presents a stress corrosion cracking index of 5.9% and the best stress corrosion resistance. While the alloy with 12.5% pre-strain shows the worst stress corrosion resistance with a stress corrosion cracking index of 41.4%. With the increase of the pre-strain degree, the difference of grain size gradually decreases, and the precipitation of the needle-like T1 phase inside the grain gradually increases and becomes finer. The matched-degree of the size, quantity and distribution uniformity of the T1 phase has a decisive influence on the strength and stress corrosion resistance of the alloy.

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    Research Progress on New Inhibitors of Saturated Linear Aliphatic Chain Monocarboxylic Acids and Their Salts for Metal Artifacts Conservation
    Ran ZHANG,Dandan ZHAO,Mo LI
    Corrosion Science and Protetion Technology. 2019, 31 (2): 232-241.   DOI: 10.11903/1002.6495.2018.111
    Abstract   HTML   PDF (1385KB)

    This review summarized recent research progress on new corrosion inhibitors of saturated linear aliphatic chain monocarboxylic acids and their salts in the field of metal artifacts conservation. These compounds show corrosion inhibition effect on lead, iron and copper alloys with advantages such as cheap, nontoxicity, environmental safety, stability and reversibility, as well as easy application and removal, so they basically meet the needs of the conservation of metal artifacts. Hence, a variety of formulas and preparation methods of inhibitors were developed. The effect of carbon chain length and concentration of inhibitors, pretreatment of substrates, temperature and time of processing, and other factors on the corrosion inhibition efficiency were studied in literatures. Finally, several trial application examples were presented of these inhibitors for the conservation of metal artifacts.

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    Leakage Analysis of Water Cooler Tube Bundle of a Hydrotreater
    Xiangchun LIU
    Corrosion Science and Protetion Technology. 2019, 31 (2): 242-246.   DOI: 10.11903/1002.6495.2018.194
    Abstract   HTML   PDF (4899KB)

    Corrosion failure analysis of water cooler tube bundle of a hydrotreater was performed with physical and chemical analysis. The results showed that the leakage of the tube bundle was caused by pitting corrosion, where local enrichment of chloride ions emerged, while the erosion of the medium aggravates the corrosion. At the last, several corrosion control measures are proposed in this paper.

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    Damage Mechanisms of Incoloy 800H Alloy Casting Under Servicing Conditions
    Lei YU,Kai LIU,Benfeng LI
    Corrosion Science and Protetion Technology. 2019, 31 (2): 247-250.   DOI: 10.11903/1002.6495.2018.268
    Abstract   HTML   PDF (5900KB)

    Cracking failure of gas collection tubes made of Incoloy 800H casting for a hydrogen converter after service for 7 a was investigated by means of OM,SEM and EPMA,with special attention on grain size assessment and microstructure characteristics of Incoloy 800H casting along and/or nearby the cracking failure. The results show that internal oxidation preferentially along grain boundaries and element segregation took place in the inner wall of Incoloy 800H casting during long term service in corrosive atmosphere at high temperature, where the alloy might experience an evolution of reaction process such as internal oxidation, followed by carbide decomposition and then by carbide segregation, as a result, the grains were coarsened and the precipitation strengthening effect was weakened, as well as the creep resistance of the carbon depleted region was then degraded, which finally leads to the initiation and propagation of cracks in Incoloy 800H alloy under the action of various type of stresses presented in the facility during service.

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