经NH4Cl沉积的MB8镁合金在含SO2气氛中的大气腐蚀

目的 通过研究NH4Cl和SO2对MB8镁合金大气腐蚀行为的影响,揭示大气环境污染因素对MB8镁合金腐蚀的影响规律.方法 在实验室进行大气(25℃,85%±5%RH)腐蚀的模拟,通过失重法、聚焦粒子束、傅立叶红外光谱和X射线衍射等手段进行表征.结果 发现NH4Cl和SO2气体均能明显的加速其腐蚀,而且两者具有协同作用.通过计算得到PB比＞1,揭示了腐蚀产物中受到压应力.结论 对腐蚀产物结构的测定,表明腐蚀产物主要是由含结晶水硫酸镁和氯化镁组成,并明确其腐蚀机理.     

大气污染对碳钢的腐蚀影响研究

总结了碳钢在亚洲地区12个试验站点的第一年大气腐蚀试验结果.研究表明,碳钢的大气腐蚀呈现明显的地区差异,不同的大气环境,腐蚀速率相差近16倍.在所研究的环境因子中,对碳钢大气腐蚀危害最大的是大气中的硫沉降因子.尤其是在中国的重庆地区,高二氧化硫污染加上湿热的气候条件,导致该地区的碳钢大气腐蚀最为严重.     

建筑结构用钢的大气腐蚀模型研究综述

腐蚀是钢结构面临的一大耐久性问题,而大气腐蚀是最常见、造成腐蚀损失最大的一类腐蚀.多年来,国内外学者通过在役结构的原位测试、大气暴露试验、室内加速试验、电化学测试等手段对各种钢材的大气腐蚀进程进行了大量研究,对不同环境中的钢材腐蚀机理进行了分析,并提出钢材的腐蚀模型.本文从典型腐蚀性大气环境中建筑结构用钢的腐蚀机理、钢材的腐蚀失重时变模型和钢材表面的蚀坑发展和分布规律等三方面论述了建筑结构用钢的大气腐蚀模型的研究现状和进展.     

煤矿区环境污染物对建筑物腐蚀研究

大气环境污染物对建筑物的腐蚀是一个普遍而又严重的问题,其中建筑物大气腐蚀所造成的损失占全部损失的50%,因此,开展大气污染物对建筑物腐蚀研究具有重要意义.以平顶山矿区为研究对象,对矿区环境大气、降水分冬、夏两季做了监测,大气环境监测因子包括SO2,NO2,HCl,Cl2,H2S,TSP和PM10;降雨(雪)监测项目包括pH值,SS,Cl-,游离CO2,CO2-3,HCO-3,NO-3,SO2-4,F-.分析了大气环境中腐蚀气体对建筑物腐蚀的影响,对混凝土碳化深度进行了测量,运用混凝土无破损检测技术检测了当前矿区混凝土构件的现状.应用X衍射对混凝土腐蚀产物做了分析,找出了影响矿区建筑物腐蚀的主要环境因素.分析了矿区建筑物腐蚀的机理,对矿区建筑材料选择和建筑物腐蚀防护具有一定的指导意义.     

金属大气腐蚀影响因素及实验方法研究综述

金属材料的大气腐蚀造成了巨大的经济损失。模拟金属材料在不同大气环境下的腐蚀并预测其长期腐蚀水平意义重大。主要阐述了腐蚀的影响因素及影响效果,综述了自然暴露实验法、湿热实验、盐雾实验、干湿交替循环实验和多因子循环复合腐蚀实验等方法的原理及应用。其中多因子循环复合腐蚀实验已成为模拟大气腐蚀加速实验的主要发展方向。     

表面沉积NaCl的紫铜在湿热环境下的大气腐蚀

目的 研究湿热条件对表面沉积NaCl紫铜的大气腐蚀行为的影响,且模拟工业大气中湿沉降物的特点,揭示大气污染环境对紫铜腐蚀的影响规律.方法 在试验室进行30 ℃、90%RH;40 ℃、90%RH;40 ℃、75%RH大气腐蚀的模拟,通过失重法、Olympus BX51M型显微镜和Rigaku D/max 2400 X射线衍射仪进行表征.结果 40 ℃、90%RH的环境下试样腐蚀程度最深,30 ℃、90%RH环境下试样腐蚀程度次之,40 ℃、75%RH环境下试样腐蚀程度最浅.温度越高,相对湿度越大,腐蚀越严重,相对湿度的增长对腐蚀的影响最为严重.结论 对腐蚀产物结构的测定,表明腐蚀产物具有较弱的保护性,并明确紫铜在湿热条件下的腐蚀机理.     

大气中SO_2对铜的腐蚀行为研究

利用三电极电化学电池和Cu/Fe双电极原电池对铜在含SO2大气中的腐蚀行为进行研究.通过电化学阻抗谱、极化曲线和电偶电流测定分析了金属铜在不同厚度液膜、不同SO2气体浓度条件下的初期腐蚀行为.结果显示:电极表面液膜越薄,金属铜的腐蚀电流密度越大;随着SO2浓度的增加,铜电极反应电阻减小,电极的去极化作用增强,Cu/Fe双电极原电池的电偶电流明显增大.     

钢结构的大气腐蚀及防护措施

了解钢结构腐蚀机理和影响因素,采取有效措施进行防护,解决钢结构大气腐蚀问题.     

新型数据管理分析系统

本文针对现有大气腐蚀数据库存原不足,在Ｗｉｎｄｏｗｓ ９５操作系统下以Ｖｉｓｕａｌ Ｂａｓｉｃ５．０为平台,辅助于Ｆｏｘｐｒｏ２．６中的库和图形编制出新型钢的大气腐蚀数据库管理分析系统。它具有数据处理、数据比较、数据查询、系数查询４个功能模块。除现有数据库的功能外,本数据库可对计算结果进行分析,更为广泛地用于材料的评价,选择设计,防腐涂层的设计和大气腐蚀原因及规律的研究。     

全国输电铁塔腐蚀情况调研

针对输电线路在役铁塔进行了一次腐蚀现状调研,从铁塔所处大气和土壤环境等方面分析了铁塔腐蚀的原因,并对相关标准进行了梳理。调研发现服役环境恶劣的乡村和大气污染严重的城市地区是腐蚀案例集中地区;黏质土和砂质土地区腐蚀案例较多,结合各个区域铁塔整体腐蚀情况提出了建议采取的腐蚀防护措施。     

Initial corrosion behaviors of AZ91 magnesium alloy in the presence of SO2

The effects of SO2 on the initial atmospheric corrosion of AZ91D magnesium alloy were investigated in laboratory. Met-allographic observation, SEM (Scanning Electron Microscopy), XRD (X-ray Diffraction) and XPS (X-ray Proton Spectrograph) were used to analyze and discuss the initial surface morphology of corrosion layers and corrosion products. The corrosion rate of the alloy increases with increasing the content of SO2. The initial attack has the characteristics of localized corrosion and preferentially concentrates on a phase. MgO and Mg(OH)2 form at first, which provide a protective layer, then the existence of SO2 decreases the pH of the thin solution on the alloy, accelerates dissolution process, and promotes the formation of MgSO3·6H2O and MgSO4·6H2O, meanwhile cracks were found on the corrosion products with corrosion continuation. These soluble corrosion products and the cracks provide the paths for filtering oxygen and corrosion pollutants into the matrix, which results in severe localized co     

Durability of asphalt mixture in different corrosion solution

The corrosion to asphalt mixture under different kinds of corrosion solution, such as pH=2 solution, pH=12 solution, pH = 12 solution and 10% Na₂SO₄ solution, was studied. The performance attenuation of asphalt mixture was analyzed under the normal environment and the freeze-thaw environment, and the analysis was given on the sensitivity of the test results to the evaluation index. The experimental results show that the performance of asphalt mixture is attenuated faster under the acidic solution, alkaline solution and sulfate solution. Corrosion factor K _c, freeze-thaw corrosion factor K _f, and freeze-thaw effect factor K _fc are proposed to evaluate asphalt mixture resistance to corrosion in different kinds of corrosion solution. The values of K _c and K _fc decrease with the increasing of corrosion time. The change rule of K _f show that the rate of corrosion is decreased by the action of freeze-thaw in acidic solution and in alkaline solution, but is increased by the action of freeze-thaw in sulfate solution. The microscopic analysis indicates that acid solution reacts with aggregate of asphalt mixture, alkaline solution reacts with asphalt cement of asphalt mixture, the surface tension of sulfate solution and crystallization of sulfate are the main reasons which weak the performance of asphalt mixture.     

大气腐蚀和气相缓蚀剂应用技术

综述了金属大气腐蚀的研究状况,介绍了大气腐蚀的研究方法和进展.简述了气相缓蚀剂的特点,讨论了气相缓蚀技术的应用形式和气相缓蚀剂的发展方向.开发新型高效、低毒气相缓蚀剂,发展气相缓蚀剂的多载体应用技术,将是气相缓蚀剂应用过程中的重点.     

电网设施防腐蚀研究进展

电网设施大量使用金属材料.近年来,大气环境污染等因素对电网设施安全经济运行造成的危害引起人们的关注.介绍了近年来国内外在电网设施安全防护方面取得的新进展,以及达克罗技术和达克罗涂层、富锌涂料和纳米技术的应用等.     

Effect of metallic phase species on the corrosion resistance of 17M/（10NiO-NiFe2O4） cermet inert anode of aluminum electrolysis

1 INTRODUCTIONThere are many disadvantages in the presentaluminumelectrolysis with carbon anode ,such assevere energy consumption,carbon wasting,envi-ronmental pollution and so on.Inert electrode sys-tem can overcome these disadvantages[1 3]. Re-cently ,the researches of the inert anode materialshave mainly been concentrated on alloys[4]and cer-met materials[5 ,6]. NiFe2O4based cermets , whichpossess not only high electrical conductivity ofmetal but also good corrosion resistance of cera…     

Electrochemical corrosion behavior of arc sprayed Zn and Zn15Al coatings in simulated salina soil and neutral meadow soil solutions

Arc sprayed Zn and Zn15Al coatings were chosen to protect the metal ends of prestressed high-strength concrete (PHC) pipe piles against corrosion of salina soil in northern china and neutral meadow soil in northeast China. The corrosion behavior of the coated Q235 steel samples in two simulated soil solutions were investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods. The experimental results show that the corrosion of the matrix Q235 steel in both simulated solutions is remarkably inhibited by Zn and Zn15Al coatings. The corrosion products on Zn and Zn15Al are thick, compact, firm and protective. The corrosion current density icorr of both Zn and Zn15Al-coated samples is decreased evidently with corrosion time, and the charge transfer resistance Rct is increased greatly. The corrosion resistance indexes of Zn and Zn15Al in simulated neutral meadow soil solution are more outstanding than those in salina soil. The corrosion resistance of Zn15Al in salina soil is slightly superior to that of Zn. When the sprayed coatings are sealed with epoxy resin, the corrosion resistance of the coatings is further enhanced markedly.