10NiCrMo钢在室内模拟海洋环境试验中的腐蚀行为

利用腐蚀电化学法及化学浸泡法研究了10NiCrMo钢在人工海水及3.5%NaCl溶液中的腐蚀行为。结果表明:10NiCrMo钢在人工海水中的自然腐蚀电位为-0.690 V,在3.5%NaCl溶液中为-0.661 V,在人工海水中腐蚀电位较在3.5%NaCl溶液中低;3个月室内全、间浸腐蚀中,腐蚀速率大小主要受氧扩散控制影响,随着腐蚀时间增长,表面锈层的增厚,10NiCrMo钢在人工海水及3.5%NaCl溶液中的全、间浸腐蚀速率随时间的延长而降低,1 500 h后趋向稳定;10NiCrMo钢在人工海水中全、间浸腐蚀速率分别为0.338~0.459 mm/a和0.279~0.435 mm/a,在3.5%NaCl溶液中全、间浸平均腐蚀速率分别为1.200~1.141 mm/a和0.840~0.404 mm/a,虽在人工海水中腐蚀电位较在3.5%NaCl溶液中低,但在人工海水中全、间浸腐蚀速率均比对应时间段内在3.5%NaCl溶液中小,在人工海水中及3.5%NaCl溶液中的间浸腐蚀速率比全浸低。     

NH3对CuZnAl合金在3.5%NaCl溶液中腐蚀行为的影响

通过对CuZnAl舍金在3．5％NaCl和3．5％NaCl＋NH，溶液中的腐蚀速率和电化学参数的测试及CuZnAl合金腐蚀形貌的观察，分析了NH3对CuZnAl合金在3．5％NaCl溶液中腐蚀行为的影响。结果表明：NH3能改变CuZnAl舍金的腐蚀形貌，使合金的腐蚀电位负移。腐蚀电流增加，合金的腐蚀速率增大。     

碳钢在NaCl溶液中初始腐蚀行为的探讨

采用电化学极化与金相显微镜原位观察相结合的方法,对Q235钢在3%NaCl溶液中腐蚀的初始行为进行了研究。借助原子力显微镜对初始腐蚀的试样观察分析,发现试样在-900 mV(vs SCE)就出现了点蚀,点蚀优先在晶界附近的铁素体上生成。蚀坑长大后,优先沿轧制方向发展,而形成腐蚀沟槽。钢中夹杂没有发生活性溶解,导电性夹杂物作为阴极仅对腐蚀过程起促进作用。     

AF1410钢电子束焊接件在模拟海洋环境中的腐蚀行为

采用中性盐雾试验模拟海洋环境,研究了AF1410钢电子束焊接接头不同位置、不同暴露时间的腐蚀电化学阻抗谱特征,并结合电子束焊接接头组织结构分析评价了焊缝熔合区及母材的耐腐蚀性能及电化学行为.开路电位及阻抗谱研究表明,焊缝熔合区的粗大回火马氏体和析出碳化物易构成腐蚀电池,比基材腐蚀反应阻力小,易引起电化学腐蚀.建立了不同腐蚀阶段的阻抗谱等效电路,并对其进行了拟合.     

Q345C-NHY3耐海水腐蚀钢的涂装腐蚀行为

以耐海水腐蚀钢Q345C-NHY3+厚浆型环氧防锈漆涂装体系为研究对象,通过漆膜理化性能检测,结合中性盐雾、紫外光老化等实验研究了Q345C-NHY3的涂装特性与涂装腐蚀行为.同时采用EIS,考察研究了涂装体系在模拟海水介质中的中长期浸泡行为.结果表明:Q345C-NHY3+厚浆型环氧防锈漆涂装体系具有良好的耐阴极剥离性能,施加阴极保护可进一步提高体系的整体耐腐蚀性能.在模拟海水的介质中浸泡104 d后,涂层体系EIS谱的低频端表现出容抗特征,这表明溶液与钢板基体发生了电化学反应,涂层体系开始失效.     

热熔浸铝Q235钢在模拟海水环境下的腐蚀行为

以Q235钢材原件、热熔浸铝一次和两次的Q235钢为研究对象,通过模拟海水（质量分数为3.5% NaCl溶液）浸泡试验,对比研究了3种试样在NaCl溶液中的腐蚀行为。利用扫描电镜观测了不同样品在腐蚀前后的表面形貌,利用失重法、交流阻抗等方法研究了热熔浸铝Q235钢的腐蚀速率。结果表明,在NaCl溶液中Q235原件腐蚀速率最快,腐蚀严重,年均腐蚀速率为0.11 mm/a;热熔浸铝一次和两次的Q235钢腐蚀速率相差不大,年均腐蚀速率分别为0.04和0.03 mm/a,热熔浸铝后Q235钢的耐腐蚀性能明显得到提高,说明热熔浸铝是一种有效提高Q235钢耐海水腐蚀性能的手段。     

镀铝钢的耐海水腐蚀性能研究

在既抗海水腐蚀又能耐磨的金属材料中，钛和钛合金是最理想的，可是价格昂贵，不锈钢虽能抗腐蚀，但在海水中却易产生点蚀，缝隙腐蚀等局部腐蚀，即使采用高合金不锈钢，要完全避免海水的腐蚀，也是不太可能的，且其价格也不并菲，碳钢虽价格较低，但其耐腐蚀性能较差，应用研究表明，镀铝钢从耐海水腐蚀，耐磨性能和成本价格等方面都优于上述三种材料，只要联接方式合适，其应用价值是其它金属材料所无法相比的。     

RE重轨钢在模拟工业大气环境下的腐蚀行为

采用周期浸润腐蚀实验结合电化学方法研究了模拟工业大气环境下RE重轨钢的腐蚀行为.结果表明,RE重轨钢的耐腐蚀性能优于不含RE的重轨钢.RE重轨钢中,RE合金元素在基体的局部富集促进了锈层中保护性好的α-FeOOH相的快速生成和含量的增加,提高了锈层阻止侵蚀性介质穿透的能力,改善了重轨钢在工业大气环境下的耐腐蚀性能.     

海洋环境用耐蚀钢研发现状及发展趋势

介绍了国内外海洋环境用耐蚀钢的发展、研发现状及耐海水腐蚀钢国内外的差距,阐明海洋环境用耐腐蚀钢的发展趋势,指出加强我国南海区域高湿热、强辐射、高Cl-环境下腐蚀机理研究,推进适应我国南海海洋环境的耐腐蚀钢板的系列化是今后重点研究课题.     

Q235钢在实际土壤与模拟溶液中的腐蚀行为

对比分析了Q235钢在实际土壤和模拟溶液中的腐蚀行为,计算了其腐蚀失重,利用SEM和XRD方法分析了两种腐蚀介质中Q235钢的锈层形貌、物相结构及相对含量,并分析了不同介质中材料的极化曲线。结果表明:Q235钢在两种不同腐蚀介质中的腐蚀行为存在较大差异。Q235钢在模拟溶液中的腐蚀速率远高于实际土壤,至周期360h达到0.413mm/a,约为实际土壤的4.5倍;Q235钢在实际土壤中呈蚀斑相连长大扩展的腐蚀形貌,其腐蚀产物为α-FeOOH、γ-FeOOH、Fe3O4和Fe2O3;模拟溶液中试样为均匀腐蚀形貌,阴极过程主要受析氢控制;随腐蚀周期的延长,内锈层中生成结晶性良好的Fe3O4,降低了试样的腐蚀速率。     

1Cr13不锈钢的土壤腐蚀行为

通过在酸性、中性及碱性土壤中埋设试件的方法,研究了１Ｃｒ１３不锈钢分别经过１年、３年、５年这三种试验周期后的腐蚀行为为特征。结果表明,１ｃｒ１３不锈钢在酸性及中性土壤中腐蚀轻微,在高盐碱必训腐蚀严重,而且以点蚀为主,土壤中Ｃｌ＾－及ＳＯ４＾２－是影响１Ｃｒ１３不锈钢腐蚀行为的最主要因素,随土壤中Ｃｌ＾－及ＳＯ４＾２－增多,１Ｃｒ１３不锈钢的腐蚀失重近似线性增大。     

应变速率对管线钢在碱性溶液中应力腐蚀行为的影响

主要研究了不同应变速率对X70管线钢在库尔勒土壤模拟溶液中应力腐蚀行为的影响.采用慢应变速率拉伸实验(SSRT)研究了不同应变速率下X70管线钢在模拟溶液中应力腐蚀开裂行为,并利用扫描电镜分析了不同应变速率下的断面形貌.结果表明,应变速率(特别是局部应变速率)对X70管线钢在库尔勒土壤模拟溶液中应力腐蚀行为有重要影响,应变速率在5×10-7～5×10-6s-1之间有较强的应力腐蚀开裂敏感性,在裂纹扩展不同阶段氢和阳极溶解交互作用相对贡献大小不同.     

Simulated Corrosion Test of Q235 Steel in Diatomite Soil

Through the study of the corrosion behavior of Q235 steel in actual Yingtan soil and two simulated acidic soils with different water contents,the calculation of corrosion mass losses,and the analysis of the corrosion morphologies and products by means of scanning electron microscope(SEM)and X-ray diffraction(XRD),the results demonstrated that the diatomite soil could simulate the corrosion in actual soil veritably.In both actual soil and simulated soil with 16.4% water content,the corrosion rates of Q235 steel were approximately 0.1mm/a,the corrosion morphologies were mainly extension and connection of corrosion spots on sample surface,and the corrosion products were composed ofα-FeOOH,γ-FeOOH,Fe3O4 and Fe2O3.When other media conditions remained unchanged,the corrosion area of Q235 steel was larger in simulated soil with 34.5% water content,and the corrosion rate reached0.48mm/a after 360 hof corrosion,which was nearly 5times as the value in actual soil.Compared with the corrosion products in actual soil,the proportion ofγ-FeOOH in simulated soil with 34.5% water content was higher,and the wα-FeOOH/wγ-FeOOHratio was 1.4,which was only 1/3of the value in actual soil.     

Effects of Niobium on the Mechanical Properties and Corrosion Behavior of Simulated Weld HAZ of HSLA Steel

Simulated microstructures of the TZ, ICHAZ, FGHAZ, and CGHAZ of weld joints made from two kinds of HSLA steels with 0 or 0.079 wt pct Nb were prepared by means of heat treatment. Optical microscopy and transmission electron microscopy were used to observe microstructures and the distribution of nanosized precipitates in the simulated weld heat-affected zone (HAZ). Mechanical properties of the simulated HAZ were measured by tensile tests, and the corrosion behavior in simulated seawater was studied using electrochemical and immersion tests. It was shown that the ICHAZ and CGHAZ possess the worst overall mechanical properties in both kinds of HSLA steels, and the corrosion resistance in the descending order was the BM, TZ, FGHAZ, ICHAZ, and CGHAZ. Contrasting Nb-bearing and Nb-free steel demonstrated that the strength and corrosion resistance of the simulated HAZ were enhanced by Nb microalloying, which resulted in precipitation, homogeneous microstructures, and other relative sequences. Moreover, the surface of the Nb-bearing steel formed compact corrosion product films with higher resistance to ion migration; thus, the initiation and propagation of pitting holes were effectively inhibited.     

Effect of Low-Temperature Environment on Stress Corrosion Cracking Behavior of X80 Pipeline Steel in Simulated Alkaline Soil Solution

Metallurgical and Materials Transactions A - The stress corrosion cracking (SCC) of X80 pipeline steel in simulated alkaline soil solution under different temperatures was investigated by...     

NSB耐蚀钢在NaCl溶液干湿交替作用下的电化学腐蚀行为

采用电化学极化曲线和阻抗谱测试方法,研究了马钢所生产NSB耐蚀船板钢在不同浓度Na Cl溶液干湿交替作用下的电化学腐蚀特征。结果表明:NSB耐蚀钢干湿交替循环试样在3.5%Na Cl溶液中的腐蚀电流密度最大,干湿交替循环在钢基体表面形成内外双锈层。红外光谱锈层相组成分析表明:干湿交替循环试样的腐蚀锈层中都含有Fe3O4和γ-Fe OOH,较高浓度的Na Cl溶液能够抑制α-Fe OOH的生成而促进β-Fe OOH的形成。     

包钢X70管线钢大气腐蚀行为研究

包钢生产的X70管线钢在露天环境中暴露放置3年后,钢管表面腐蚀并不严重,具有类似耐候钢的腐蚀形貌特征,而国内某钢厂生产的X70管线钢在相同环境下放置相同时间后,表面腐蚀较为严重,文章通过采用周期腐蚀试验对包钢生产的X70管线钢与国内某钢厂生产的X70管线钢进行对比分析,研究包钢X70管线钢耐大气腐蚀行为规律。     

Corrosion Behavior of S450EW Low-alloy Weathering Steel in Cyclically Alternate Corrosion Environments

Weathering steel is widely used in various fields due to its excellent mechanical properties and high corrosion resistance. The effect of chromium content on the S450 EW weathering steel in cyclic immersion test was studied. The results indicated that the corrosion resistance of S450 EW weathering steel is closely related to chromium content. The addition of chromium significantly inhibited the weathering steel corrosion. The corrosion rate of experimental steel after 96 h immersion was 1.101 g·m-2·h-1. The rust of S450 EW weathering steel was mainly constituted of Fe OOH and Fe3O4 phase, and the elevation of chromium content promoted the formation of α-Fe OOH. The fine precipitates of the two phases contributed to the formation of dense dust layer of test steel. Furthermore, the increase of chromium is beneficial for the cure of original defects and cracks of the rust layer via the enrichment of chromium. The corrosion potential and the resistance of corrosion process were thus increased, protecting the experimental steel from further corrosion. A S450 EW steel with corrosion resistance more than 1.5 times of Q450NQR1 steel was prepared.