海洋钢结构浪花飞溅区腐蚀防护技术

随着我国对海洋资源的开发,海洋钢结构的腐蚀控制技术越来越受到关注。海洋环境可以分为海洋大气区、浪花飞溅区、海水潮差区、海水全浸区和海底泥土区等5个腐蚀区带。其中,海洋钢结构在浪花飞溅区腐蚀最为严重。在浪花飞溅区,钢表面受到海水的周期性润湿,处于干湿交替状态,氧供应充分,盐分不断浓缩,加之阳光、风吹和海水环境等协同作用导致发生最严重的腐蚀。锈层的自氧化反应是加速钢结构在浪花飞溅区腐蚀的一个主要原因。当前,国内对于海洋钢铁设施大气区通常采用涂料保护,海水全浸区采用电化学保护,都取得了较好的保护效果,但是这些保护技术对于钢结构在浪花飞溅区的腐蚀防护效果并不佳。而复层矿脂包覆防腐（PTC）技术是当前海洋钢铁设施浪花飞溅区防腐蚀应用较为理想的方法,对此进行了重点介绍。     

Q500qENH耐候桥梁钢在模拟工业大气环境中的腐蚀行为

通过周期浸润腐蚀试验对比研究了鞍钢生产的耐候桥梁钢Q500qENH和传统耐候钢09CuPCrNi在模拟工业大气环境中的腐蚀行为,并采用腐蚀形貌观察和电化学测试等手段对其腐蚀行为进行了分析。结果表明:显微组织和化学成分对钢基体的耐蚀性均具有一定影响,当保护性锈层形成后,耐蚀性主要取决于锈层的保护作用;周期浸润腐蚀试验结果和带锈试样的电化学阻抗谱、线性极化曲线分析表明Q500qENH钢耐工业大气腐蚀的能力优于09CuPCrNi钢的。     

海水飞溅区Ni-Cu-P钢的锈层和耐点蚀性能研究

在海水飞溅区对实验室冶炼的Ni-Cu-P钢、含Cu低合金钢和碳钢进行660 d的挂片实验,评价Ni-Cu-P钢的耐蚀性能;采用Fourier变换红外(FTIR)光谱、电感耦合等离子体原子发射光谱(ICP-AES)、电子探针(EPMA)、SEM和EDAX等技术,分析3种钢表面的锈层特征.结果表明,Ni-Cu-P钢表现出比...     

Characterization of rust phases formed on low carbon steel exposed to natural marine environment of Chennai harbour – South India

The corrosion behaviour of low carbon steel exposed to marine atmospheric, splash and immersion zones has been systematically studied by exposing steel specimens for a period of 12 months at the boat basin corrosion station of Chennai harbour, Chennai, Tamil Nadu, South India. The literature on similar work has been thoroughly reviewed which led to the initiation of this study for the first time at this harbour. The corrosion product (rust) on the specimens at 1, 2, 3 and 12 months was obtained and characterized by Fourier transform infrared spectroscopy (FT‐IR) and X‐ray diffraction (XRD) analysis. Acaganeite was the rust phase identified in the splash zone as revealed by the FT‐IR and XRD analysis. The other dominant phases were lepidocrocite, goethite and ferroxyhite. Small amounts of magnetite were also found to be present. The transformation of phases was observed in this investigation and discussed. A remarkable difference in the FT‐IR and XRD patterns of the corrosion products at the splash and immersion zones were noticed and the corresponding phases formed were reported in this paper. The rate of corrosion in all the three zones was compared.     

碳钢和耐候钢在北京城市大气环境中初期腐蚀行为

对碳钢和耐候钢在北京城市大气中的初期腐蚀行为进行了研究．主要采用金相、扫描电镜、X-射线衍射方法分析和探讨了初期腐蚀层形貌、腐蚀产物和合金元素的分布．结果表明：在腐蚀初期，耐候钢表面生成的锈层较碳钢致密，裂纹和孔洞相对较少；25d后碳钢和耐候钢局部都出现了分层现象。腐蚀产物没有区别，差别主要是锈层中合金元素的作用．耐候钢锈层中有Cu、Cr合金元素的析出，聚集在裂纹处可抵御大气中水气及其有害离子的侵入，防止基体金属进一步腐蚀．     

Corrosion Evolution of Steel Reinforced Concrete Under Simulated Tidal and Immersion Zones of Marine Environment

The corrosion evolution processes of steel reinforced concrete under simulated tidal and immersion zones of marine environment were investigated by using electrochemical measurements and corrosion morphology observations.The results indicate that the corrosion of rebar in concrete under both environments experiences the deterioration from passivation to pitting corrosion and then to general corrosion.Specially,the pitting plays the major role only in the early stage of corrosion,and the general corrosion replaces the dominate role of pitting during the long-term corrosion.In addition,both the pitting depth on local surface and the rust thickness on the overall surface of rebar in the tidal condition are larger than those in immersion condition,which is attributed to the faster corrosion rate in tidal zone caused by the concentrated chloride ions and sufficient oxygen supply.     

DH36钢在需钠弧菌、芽孢杆菌以及混菌腐蚀体系中的腐蚀行为

目的研究需钠弧菌与芽孢杆菌分别单独培养以及混合培养时对海洋工程钢DH36腐蚀行为的影响,为海洋环境下材料的腐蚀发生规律探讨以及微生物腐蚀防治提供依据。方法通过扫描电子电镜、能谱仪、电化学设备等仪器,分析DH36钢在不同腐蚀体系中的腐蚀形貌信息以及电化学特征。结果SEM图显示,芽孢杆菌在DH36钢表面上的贴附量较大,需钠弧菌与混菌腐蚀体系中,生物膜、锈层构成的混合层存在很多的裂纹、缝隙,致密性较差。电化学结果显示,试样表面均出现两个时间常数,在低频处出现感抗特征。芽孢杆菌腐蚀体系中的腐蚀速率先增大后减小,浸泡3 d后需钠弧菌腐蚀体系中的腐蚀速率介于芽孢杆菌与混菌腐蚀体系之间。与单菌种腐蚀体系相比,混菌腐蚀体系中的开路电位最低,且浸泡7 d后的腐蚀速率最大,达到13.53μA/cm^2。结论在浸泡后期芽孢杆菌显示出腐蚀抑制效果,在需钠弧菌与混菌腐蚀体系中,由于细菌代谢产生了腐蚀性产物以及形成了致密性较差的混合层,试样腐蚀速率不断加快,但混菌的促进作用更显著。     

带锈铸铁在3.5%NaCl溶液中的腐蚀行为研究

采用增重法和强极化、线性极化技术,研究了已生成较厚砂锈层的带锈铸铁在３．５％ＮａＣｌ溶液中的腐蚀与电化学行为,分析较厚砂锈层对铸铁腐蚀的影响,结果表明,带锈铸铁的腐蚀速度比裸铸铁的腐蚀速度大,较厚砂锈层不仅不能阻碍腐蚀过程继续发展,而且还有加速腐蚀发展的趋势。带锈铸铁的间浸腐蚀速度比全浸快得多,较厚砂锈层使间浸对带锈铸铁的腐蚀加速作用比对裸铸铁的加速作用更大。     

Influence of outer rust layers on corrosion of carbon steel and weathering steel during wet–dry cycles

The influence of the rust layers of carbon steel and weathering steel on the corrosion were investigated. It was found that corrosion of carbon steel slows down when its outer rust layer is removed. This phenomenon might be attributed to the shortening of the wetting time in wet–dry cycles when the outer rust layers are removed. What is more, growth time of the corrosion products is shortened as well, which results in the formation of the fine corrosion products. However, the behavior of corrosion of weathering steel is not obviously influenced by the outer rust layer and the wetting time.     

低碳钢在模拟海洋潮差区的腐蚀行为的电化学研究

利用自主设计的腐蚀实验槽模拟实海潮差,并借助恒电位仅、电化学工作站对Q235B低碳钢在潮差区不同位置以及全浸区的腐蚀过程进行原位监测.结果表明,试样处在潮差区的不同位置时的腐蚀规律不同,低碳钢在中潮区和低潮区的腐蚀速率高于最高潮区及全浸区的腐蚀速率;在一个潮差涨落周期内,低碳钢开路电位的变化与表面经历的干、湿状态及所发生的阴、阳极反应有关;在长期潮差腐蚀进程中,低碳钢开路电位的变化规律与锈层的厚、薄状态有关.     

低碳钢在模拟海洋潮差区的腐蚀行为的电化学研究

利用自主设计的腐蚀实验槽模拟实海潮差,并借助恒电位仪、电化学工作站对Q235B低碳钢在潮差区不同位置以及全浸区的腐蚀过程进行原位监测.结果表明,试样处在潮差区的不同位置时的腐蚀规律不同,低碳钢在中潮区和低潮区的腐蚀速率高于最高潮区及全浸区的腐蚀速率;在一个潮差涨落周期内,低碳钢开路电位的变化与表面经历的干、湿状态及所发生的阴、阳极反应有关;在长期潮差腐蚀进程中,低碳钢开路电位的变化规律与锈层的厚、薄状态有关.     

Corrosion of copper in seawater and its aerosols in a tropical island

A complete characterization of copper corrosion behavior has been carried out under permanent immersion, water line, splash zone and at the atmosphere (near and far from the sea) at the tropical Cuban archipelago. No significant differences have been determined for corrosion of copper under complete immersion for test sites representative of Cuban archipelago. The maximum corrosion rate was observed on the line of water, related to the partial removing of the corrosion products layer due to water movement (waves) and a higher availability of oxygen. Patina composition was characterized using XRD, IR, EDS and SEM techniques. Paratacamite (Cu₂(OH)₃Cl) was the main component of the patina formed under complete immersion, on the line of water and in the splash zone. In poorly polluted atmospheric marine environments also atacamite (another structural modification of Cu₂(OH)₃Cl) was found. When environmental SO₂ reaches a competitive level with the chloride aerosol the patina formed is a complex mixture of basic cupric chlorides (paratacamite and atacamite) and basic cupric sulfates, antlerite (Cu₃(SO₄)(OH)₄) and brochantite (Cu₄(SO₄)(OH)₆). Brochantite and basic cupric chlorides are detected at inland rural sites. The patina morphology reveals details about the local environment in which it is formed and shed light on its more or less protective role for the metal. The relatively large corrosion rate under complete immersion and on the line of water is related to the formation of a patina with poor adherence to the metal surface and to a porous layer of cuprite formed by relatively large octahedral crystals.     

Corrosion Behavior of High-Strength Steel for Flexible Riser Exposed to CO_2-Saturated Saline Solution and CO_2-Saturated Vapor Environments

The corrosion behavior of high-strength steel used for flexible riser exposed to CO_(2-)saturated saline solution and CO_(2-) saturated vapor environments was studied through immersion experiment and electrochemical corrosion experiment. The corrosion behavior and mechanism of the tested steel were analyzed on the basis of corrosion kinetics, nature of corrosion products, corrosion product morphology, elemental distribution and polarization curves. The experimental results showed that the microstructure of the tested steel was bainitic microstructure. The corrosive activity of the tested steel exposed to CO_(2-) saturated vapor environment was significantly lower than that exposed to CO_(2-) saturated saline solution environment.On prolonging the exposure time, the corrosion rate gradually decreased, the corrosion heterogeneity increased, and the dimensions of FeCO_3 crystals gradually became small. At later stages of corrosion, the corrosion current density decreased significantly and the anodic Tafel slope increased, indicating that the corrosion process was strongly inhibited. The corrosion mechanism of low-alloy steel with bainitic microstructure was proposed based on experimental results.     

周期干湿浸条件下P265GH钢和Q235钢的大气腐蚀行为简

以NaCl+NaHSO3为腐蚀介质,通过浸渍干湿复合循环实验及腐蚀失重分析,并利用SEM,XRD和FTIR技术,研究了Q235碳钢和P265GH低合金钢的大气腐蚀行为。结果表明,两种钢的腐蚀遵从相同的动力学规律,腐蚀产物中均存在大量致密的α-FeOOH和非晶态δ-FeOOH,锈层具有很好的保护性,使得腐蚀速率降低。实验开始阶段两种钢的腐蚀量基本相同,但随着腐蚀的进行两者差距增大,P265GH低合金钢较Q235碳钢的失重小、锈层致密、耐腐蚀性好。     

含镀层合金钢循环盐雾加速腐蚀行为与机理研究

目的 研究含镀层合金钢在室内模拟及强化腐蚀环境下的腐蚀行为与机理,建立快速评价含镀层钢腐蚀寿命的加速试验方法.方法 利用设计的室内加速腐蚀环境试验谱,通过实施模拟海洋大气环境效应的循环盐雾加速腐蚀试验,采用外观检查、SEM、XRD及电化学测试等手段,表征了暴露不同周期样品的腐蚀失重、腐蚀形貌、腐蚀产物成分、极化曲线及阻...     

热喷Zn涂层浪花飞溅区腐蚀的室内模拟研究

海盐粒子浓度大、干湿交替频繁、海水冲击是浪花飞溅区腐蚀的3个关键性因素。文中以热喷Zn涂层为研究对象,设计了4种循环腐蚀试验制度:①盐雾–驻留循环;②盐雾–驻留–飞溅循环;③盐雾–干燥循环;④盐雾–干燥–飞溅循环,采用失重测量和电化学测量分别研究了涂层在这4种模拟环境下的腐蚀行为及规律,并应用加速转换因子法及灰关联分析对各循环腐蚀试验制度下的加速性、模拟性进行了研究,并为此设计了一个飞溅模拟研究装置以实现浪花飞溅冲击的模拟。试验结果表明:盐雾+驻留循环造成涂层的腐蚀最严重;盐雾+驻留+飞溅循环则能较好的模拟浪花飞溅区的腐蚀情况,可实现室内的热喷Zn涂层在浪花飞溅区腐蚀的模拟。     

海水中带锈Q235钢腐蚀电化学参数测定

利用失重法和电化学方法对在海水中浸泡不同时间的Q235钢电极的腐蚀行为和腐蚀速率规律进行了研究。结果表明,对于长期浸泡的Q235钢电极,失重法和电化学方法得到的腐蚀速率结果存在很大差异。利用XRD测定了长期浸泡后锈层成分的变化,发现长期浸泡Q235钢电极锈层中的电化学活性成分β-FeOOH在测试过程中发生还原反应,导致利用电化学方法测得的Q235钢腐蚀速率大于失重法的结果,并且随浸泡时间的延长,这一偏差增大。对长期浸泡Q235钢电极进行电流密度为-25 μA/cm²阴极恒电流预极化处理后发现,随着浸泡时间的延长极化时间也延长,同时,经过预处理之后的Q235钢电极电化学方法测得的腐蚀速率与失重法的结果具有一致的变化规律,表明施加合适的阴极极化预处理能够减小电化学方法与失重法测试结果的偏差。     

氯离子和直流电流密度对X65钢的腐蚀研究

目的通过浸泡实验和腐蚀图像表征方法研究氯离子和直流杂散电流共同作用下X65钢的腐蚀特征。方法通过浸泡实验,在不同氯离子浓度和直流电流密度的共同作用下,通过失重法计算X65钢的均匀腐蚀速率。通过三维显微镜对浸泡后的腐蚀形貌进行观察,确定其主要腐蚀形态和发展规律。结果在不同的氯离子浓度下,X65钢的均匀腐蚀速率基本不变,误差主要来自于腐蚀产物清洗不彻底和环氧树脂吸水的差异性。而腐蚀速率与直流电流密度成正比,氯离子主要作用是使试片形成不同的局部腐蚀特征,破坏了试片表面的均匀腐蚀,而加剧了局部腐蚀,但对整体的腐蚀速率基本没有影响。结论引起管道腐蚀失重的主要因素为流出管道的直流电流密度,而与所处环境无关。低氯离子浓度是导致局部腐蚀的主要原因,随着氯离子浓度的增大,腐蚀逐渐向均匀腐蚀转变。直流电流密度造成的腐蚀以均匀腐蚀为主。     

Al及Al合金在舟山海域的腐蚀行为

报告Al及Al合金在舟山海域的飞溅区、潮差区和全浸区3种试验条件下暴露2、4、8年的腐蚀结果及其在海水环境中的腐蚀行为.Al及Al合金在海洋环境中的平均腐蚀率较低,主要因点蚀、缝隙腐蚀而受到破坏,硬Al、超硬Al的包Al层对基体起着牺牲阳极保护作用.在飞溅区,Al及Al合金对局部腐蚀较敏感,点蚀密度较大.在飞溅区,二种带包Al层的LC4CS(BL)、LY11CZ(BL)耐蚀性较好,L3M和LF11M的耐蚀性较差;在潮差区和全浸区180YS和LF2Y2表现出较好的耐蚀性.LF11M在潮差区的耐蚀性较好,而在飞溅区和全浸区的耐蚀性较差.     

Cu,P,Cr 和 Ni 对低碳钢耐蚀性的影响简

选择Cu-P-Cr-Ni钢、Cu-P-Cr钢和Q235碳钢,在0.01 mol/L的NaHSO3溶液中进行周期浸润、阻抗谱和极化曲线实验,研究了Cu-P-Cr-Ni系合金钢相比Q235碳钢在模拟工业大气(SO2)环境下的耐腐蚀性能;利用SEM,EPMA面扫描和XRD分析腐蚀锈层的形貌、组成及Cu,Cr和Ni的元素分布情况。结果表明:Cu-P-Cr-Ni系钢的腐蚀诱发敏感性最低,其次为Cu-P-Cr钢,腐蚀速率分别为Q235碳钢的59.5%和52.8%;锈层分为内、外两层,致密的内锈层明显发生Cu的颗粒状、Cr的团聚状富集,外锈层主要有Cr的富集,Ni富集不明显。Cu和Cr等的富集可形成致密的内锈层,提高低碳钢的耐蚀性。