铜合金在海水中暴露4年的腐蚀行为

对12种铜及铜合金在榆林站的海水全浸区进行了为期4年的实海暴露腐蚀试验。总结和分析了各种铜合金的腐蚀行为和抗污性;研究和探讨了铜合金在热带海水中的腐蚀规律及原始表面状态对铜镍合金腐蚀稳定性的影响。     

3种船用钢在南海海洋环境中8年的腐蚀行为

研究了３Ｃ（Ｗ ）、１６Ｍｎ、９２１ 三种钢在南海榆林海域全浸、潮差、飞溅环境中暴露８ 年的腐蚀行为。其中,９２１ 钢在飞溅区具有优良的耐蚀性,而在全浸和潮差区耐蚀性不如３Ｃ（Ｗ）钢和１６Ｍｎ 钢的。发现９２１ 钢在全浸区暴露２ 年后发生腐蚀率随时间增加而增大的“逆转”现象。     

10种钢样在不同海水环境的潮差区和全浸区腐蚀规律研究

为研究厦门、湛江和青岛的潮差区和全浸区的腐蚀规律,通过现场暴露试验,获得了10种钢样(含碳钢和低合金钢)暴露7a的腐蚀结果,采用线性拟合的方法对数据进行了处理.结果 表明:在3个地点,腐蚀速率的基本规律为青岛＞湛江＞厦门,腐蚀速率与海生物污损密切相关.在3个暴露地点,全浸区前期腐蚀量低于潮差区而后期腐蚀量增速高于潮差区.在厦门暴露2a时,全部试样在2个区带的腐蚀率出现逆转,而在湛江和青岛,在7a时几乎所有试样均出现逆转.在厦门潮差区,合金元素的加入对提升钢的耐蚀性无明显的效果,甚至存在负面影响;在湛江潮差区和青岛潮差区,无论从短期还是长期来看,合金元素的加入都有利于提升钢的耐蚀性.在厦门全浸区和湛江全浸区,无论是短期还是长期来看,所有类型的碳钢和低合金钢腐蚀速率均接近;在青岛全浸区,无论是短期还是长期来看,加入合金元素对耐蚀性均有所提升,短期的效果更为明显.     

B30铜镍合金在海水中的电化学行为

B30铜镍合金具有优良的耐海水腐蚀性能,但在海水中形成的表面膜对其自身的电化学行为有影响,过去对此研究不多.采用交流阻抗、线性极化、动电位极化、循环阳极极化等方法研究了B30铜镍合金表面在海水中形成的氧化膜对其自身腐蚀电化学行为的影响,采用原子力显微镜(AFM)对氧化膜的结构进行了分析.结果表明:B30铜镍合金在海水中浸泡72 h后,表面能够生成一层完整致密的氧化膜;表面膜使B30铜镍合金在海水中的阻抗值随浸泡时间的延长先增大后减小,而且能够降低其极化电流密度以及瞬时腐蚀速率;随着浸泡时间的延长,B30铜镍合金在海水中的点蚀倾向加重.     

B10铜镍合金海水加速腐蚀行为

B10铜镍合金具有优良的耐海水腐蚀性能,为研究其在海水中的腐蚀行为,取厦门天然海水,加入双氧水作为腐蚀加速剂,在室内模拟海水全浸腐蚀实验,采用失重法、电化学阻抗谱(EIS)技术分析B10合金在海水腐蚀中的腐蚀速率随腐蚀时间的变化规律,用不同腐蚀周期的电化学阻抗谱特征来表征工作面积为1cm~2的合金表面氧化膜的生长破坏情况。结合扫描电子显微镜(SEM)、能谱分析(EDX)、XPS和拉曼光谱技术分析B10合金表面腐蚀产物膜的成分以及B10合金在海水腐蚀中的腐蚀类型。结果表明,氧化膜的生成与破坏使得合金在海水中的瞬态腐蚀速率呈先减小后增大的趋势,腐蚀产物包含碱式氯化铜Cu_2(OH)_3Cl和氧化亚铜Cu_2O,腐蚀由点蚀开始,逐渐经历了晶间腐蚀-剥蚀。     

不锈钢在厦门海域的长周期腐蚀行为

选择5种典型不锈钢，采用国家标准方法进行厦门海域全浸区和潮差区的实海腐蚀暴露试验。16年腐蚀试验结果表明，5种不锈钢主要腐蚀形态是点蚀、溃疡腐蚀、隧道腐蚀和缝隙腐蚀。在全浸区的腐蚀比潮差区的严重。两区带耐蚀顺序一致，耐蚀性最好的为000Crl8Mo2，其余依次为00Crl9Nil0、1Crl8Ni9Ti、F179和2Crl3。     

铜及其合金在青岛海域的腐和污损

介绍了１２种铜及其合金在青岛海域暴露１，２，４，８年的腐蚀结果，讨论了它们在海水中的腐蚀和污损行为。     

铜及铜合金在泥沙海水中的腐蚀研究

介绍了 9种铜及铜合金在舟山海域暴露 1、2、4、8a的腐蚀结果 ,并通过室内模拟泥沙海水的加速腐蚀试验 ,研究了这些铜及铜合金在泥沙含量分别为 0 ,0 .75‰ ,1 .5‰的海水中的冲刷腐蚀行为及海水的泥沙含量对铜及铜合金的腐蚀形貌和腐蚀率的影响。结果表明 ,海水中泥沙的存在会加剧铜及铜合金的腐蚀 ,海水的泥沙含量对铜及铜合金腐蚀的影响程度随合金的不同有很大变化。     

试验材料及试验方法

为了系统积累和研究常用材料在我国南海海洋环境中的腐蚀数据和规律,在榆林站开展了海水全浸、潮差、飞溅腐蚀试验,取得了4年的腐蚀数据及规律。介绍了试验材料和暴露腐蚀试验方法。     

铜及其合金在青岛海域的腐蚀和污损

介绍了12种铜及其合金在青岛海域暴露1、2、4、8年的腐蚀结果,讨论了它们在海水中的腐蚀和污损行为。     

Investigation of corrosion and mechanical properties of Al–Cu–SiC–xNi composite alloys

In this study, dry sliding wear behavior and corrosion resistance of Al–Cu–SiC–xNi (x: 0, 0.5, 1, 1.5 wt.%) composites were investigated. Effect of nickel content on the microstructure and hardness of the alloys was also studied. Wear tests were conducted using a ball on disc wear test device. Corrosion behavior of Al–Cu–SiC–xNi composite alloys in 3.5% NaCl solution was investigated by using potentiodynamic polarization, impedance spectroscopy and cronoamperometric methods. The results showed that the hardness of the composite alloy increases with increasing nickel content. Maximum wear resistance is reported with the addition of 1 wt.%Ni. It was determined that corrosion resistance of Al–Cu–SiC composite alloys improved with increasing nickel content in the alloy.     

Effect of deposition rates on overlay coating structure

Surface alloys were fabricated by the implantation of 25 keV chromium and nickel ions into polycrystalline iron in doses ranging from 1.0 × 10¹⁶ to 4.0 × 10¹⁶ ions cm^-2. The alloy distribution as a function of depth (depth profile) was determined for the Fe-Cr and Fe-Ni surface alloys, and the results were compared with theoretical predictions. The resistance of the surface alloys to environmental attack was evaluated both by determining their anodic polarization behavior under potentiostatic conditions in a buffered boric acid solution and by determining their gaseous oxidation characteristics. The results of the electrochemical studies showed that the general corrosion resistances of the surface alloys are comparable with those of nominally equivalent bulk alloys and that the pitting-corrosion resistances of the surface alloys are superior to that of iron, although generally they are not as good as those of most equivalent bulk alloys. The gaseous oxidation studies showed that surface and bulk Fe-Cr alloys exhibit essentially identical oxidation kinetics, with a much higher rate of oxidation being observed for iron. In both the aqueous corrosion and the gaseous oxidation studies the quantity of the alloying element in the surface alloys was six to seven orders of magnitude less than that in the equivalent bulk alloys.     

Effect of Ammonia and Sulphide Environment on 90/10 and 70/30 Cupronickel Alloy

Copper nickel alloys 90/10 and 70/30 are used extensively in saltwater systems operating on marine platforms and offer high corrosion and biofouling resistance. However, systems using these materials were reported to fail prematurely. Preliminary investigations revealed pollution of harbor waters with tangible levels of ammonia and sulphides which was reported to be the primary cause of failure. The present author(s) have performed laboratory and field investigations to identify the stress-material-environment interaction of the copper nickel alloys extensively in use on seawater system of marine platforms. Results obtained point to the fact that polluted seawaters can affect the material properties of the alloy leading to premature failure(s) of systems at stresses well below the designed stress. The paper presents the correlation of the results of the laboratory and field tests of 90/10 and 70/30 copper–nickel alloys in seawaters polluted with ammonia and sulphide pollutants.     

Korrosion in Carbonsäuren. Teil I: Anwendung von Radionuklidtechnik und Impedanzspektrometrie auf Korrosionsuntersuchungen metallischer Werkstoffe

Corrosion in Carboxylic Acids – Part I: The Application of Radionuclide Techniques and impedance Spectrometry in Corrosion Studies of Metallic Materials Within the ?Corrosion and Protection”? research and development program, studies have been conducted on the corrosion of metals in low carboxylic acids. A radionuclide method has been employed to measure corrosive abrasion, and the technique of impedance spectrometry has been used to trace the electrochemical corrosion reactions. In this first communication, these methods of measurement are described and their uses and the kinds of information to be obtained from them are discussed. The corrosion systems studied, i.e., some high-alloy steel grades and nickel base alloys in formic acid and acetic acid with a number of additives, are indicated.     

铜合金在海水中的腐蚀行为研究

通过高速旋转腐蚀试验，X射线衍射，扫描电镜（SEM）及能谱分析（EDAX），高化学特征测定等对Cu-2,9Sn-0.9Al铜合金在人工海水中的腐蚀行为进行了研究，结果表明，添加2.9%Sn,0.9%Al的铜合金在室温，pH值为8．2的人工海水中具有较好的耐腐蚀性，其高耐蚀性主要是由于在合金表面形成一层氧化膜，它对阳极过程和阴过程都有影响，这层膜是Cu的氧化物和Sn的氧化物及Cu-Al-Mg共析化合物的复合保护膜，它们的协同作用降低了氧化层的孔隙度，从而避免了局部酸性区域的形成而导致的局部腐蚀。     

真空熔炼多组元Cu_xAlFeNiCrTi高熵合金的显微组织和性能

多组元高熵合金是一种具有五种以上组元的新型合金。通过真空电弧熔炼炉熔铸得到了不同铜含量的高熵合金Cu_xAlFeNiCrTi(x=1和0.5),再通过光学显微镜、X射线衍射仪、扫描电镜、透射电镜以及显微硬度计分析了高熵合金的显微组织、结构、硬度和耐腐蚀性能等。结果表明:高熵合金具有简单的相结构,合金硬度在800 HV以上,耐碱腐蚀性能优于耐酸腐蚀性能;随着铜元素含量的减少,合金结构由体心立方+面心立方结构变为体心立方结构,合金硬度增加,耐腐蚀性能提高。     

镁及镁合金腐蚀最新研究进展

镁的平衡电位非常低，耐蚀性差，长期以来阻碍了镁及镁合金的应用，对近十年来国内外关于镁及镁合金的腐蚀行为以及表面防腐技术的研究进行了综述。     

贮氢合金V3TiNi0．56Alx耐碱液腐蚀性能研究

钒基固溶体贮氢合金V3TiNi0．56由于其可逆吸放氢量大，作为镍氢电池负极材料有很大的应用前景。但合金的耐碱液腐蚀性能差，导致合金循环寿命短达不到应用要求。主要研究了合金元素Al对钒基固溶体贮氢合金耐碱液腐蚀的影响。测试V3TiNi0．56Alx合金电极的腐蚀电位、均匀腐蚀全浸试验过程中的质量损失率和组织变化，发现：V3TiNi0．56Alx合金中Al含量增加，腐蚀电位正移，腐蚀质量损失率减小，晶界的网状结构消失速度变慢，耐碱液腐蚀性能提高。     

Serviceability of 35KhF steel in hydrogen-sulfide media

Corrosion and corrosion-mechanical properties of 35KhF low-alloyed steel in hydrogen-sulfide media are investigated. The corrosion resistance and resistance to hydrogen-induced cracking of the steel of different heats in NACE solution and artificial seawater, and its resistance to hydrogen-sulfide stress corrosion cracking in the NACE solution are determined. It is shown that 35KhF steel can be used for the manufacture of critical components of a lift string for pumping-over stratal water.     

Korrosion in Carbonsäuren Teil II: Das Korrosionsverhalten hochlegierter Stähle,zweier Nickellegierungen und von Titan in Ameisensäure

Corrosion in Carboxylic Acids-Part II: The Corrosion Behavior of Stainless Steels, Nickel Alloys and Titanium in Formic Acid The corrosion behaviour of 4 steels, 2 nickel alloys and titanium was studied in formic acid at boiling temperature and some lower temperatures. A radionuclide methode and impedance spectrometry have been used for investigations. The decomposition products H₂O and CO influence the corrosivity of formic acid against steels. The steels and the alloys 2.4858 show a maximum of corrosion attack with following decreasing corrosion rates. From the impedance spectra the formation of adsorbed layers is to be seen which discintegrate during anodic polarization. The dynamic behaviour of 2.4858 is that of an ideal passive electrode. The impedance spectrum of titanium is determined by th enature of the passive layer.