BNQ系列冷轧耐候钢的耐蚀性能

通过大气腐蚀试验、室内加速腐蚀试验、电化学测试和锈层分析，研究了ＢＮＱ系列冷轧耐候钢的耐腐蚀性能。结果表明不仅有低的腐蚀率而且有好的耐锈稳定性和适应性。并详细讨论了该钢种具有高耐候性的原因。     

JT245经济型耐候钢锈层的电化学研究

从电化学的角度出发,采用自然腐蚀电位测定、线性极化、阳极极化、交流阻抗等试验方法对经济型耐大气腐蚀钢JT245的锈层和裸钢的耐大气腐蚀性能进行了实验研究,并与Q235B及Corten A钢进行了对比.试验表明：JT245钢在大气腐蚀过程中生成的锈层,使电化学阳极过程受到显著的阻滞.从热力学上看,JT245钢的自然腐蚀电位正移;从动力学上看,锈层表面趋于钝化,阳极电流降低两个数量级以上.     

10PCuRE耐候钢耐蚀锈层的电化学特征

利用干湿周浸实验室加速腐蚀方法获得了不同稀土含量10PCuRE耐候钢和碳钢的腐蚀率,采用测定带锈试样阳极极化曲线、弱极化区线性极化曲线和交流阻抗谱的方法评价了耐候钢和碳钢生成锈层的性能,从电化学角度解释了钢样耐蚀能力的差别,并且得出稀土在一定的含量范围内可以减小腐蚀驱动力,促进锈层稳定致密化的结论。     

耐大气腐蚀钢锈层的X射线衍射与SEM分析

讨论了Ｓｅｍａｎｎ－Ｂｏｈｌｉｎ薄膜衍射方法，并将该方法与常规Ｂｒａｇｇ－Ｂｒｅｎｔａｎｏ衍射方法、ＳＥＭ方法一起应用于耐大气腐浊钢锈蚀产物的研究，取得了初步进展     

耐候钢锈层及其稳定化处理现状

耐候钢具有良好的耐大气腐蚀性,但是稳定化锈层形成较慢,在耐候钢使用前对表面进行预处理,可以缩短锈层稳定化形成时间和防止锈液流挂.简要概述了国内外耐候钢的发展情况,以及耐候钢稳定化锈层的形成过程和锈层的组成与结构,分为以γ-FeOOH为主的疏松外锈层和以α-FeOOH为主的致密内锈层;介绍了表面锈层保护机理,包括物理阻隔...     

高氮耐候钢锈层的电化学与物相表征

为了考察氮元素对耐候钢耐腐蚀性能的影响,研究制备了氮质量分数分别为0.0358%和0.0026%的高氮耐候钢和低氮耐候钢。应用电化学阻抗谱和X射线衍射(XRD)分析、电子探针(EPMA)面扫描技术研究了两种实验钢在模拟工业大气溶液中腐蚀电化学过程和锈层结构的异同。电化学阻抗谱显示,高氮耐候钢在高频段(点蚀诱发期)比传统耐候钢有着更加优良的耐点蚀能力,低频段(扩散型阻抗生成期)则显示腐蚀产物层具有更高的阻抗,抵御腐蚀介质侵蚀的能力较强。X射线衍射和电子探针分析结果表明耐候钢高氮含量促进了稳定结构锈层生成,锈层中非晶态α-(Fe_1-xCr_x)OOH的分布更广泛、连续,提升了耐候钢抵御Cl^-侵入的能力。高氮钢腐蚀坑具有大宽深比的特征,内锈层较薄,证明其具有良好的抑制点蚀能力。     

经济耐候钢的研究

系统研究了Mn、Cu含量及腐蚀环境体系对协同作用的影响,并利用电化学测试、扫描电镜、XRD等材料分析技术对带锈电极的腐蚀行为、锈层组成、结构和性质进行了深入分析,阐述了Mn-Cu合金化协同作用的机制;利用Mn-Cu合金化的协同作用,成功开发出Mn-Cu型经济耐候钢和实现工业化试生产。实验表明：热轧Mn-Cu钢具有良好的耐候性,其耐候性略优于传统的09CuPTiRE和SPA-H耐候钢。     

新型耐海水腐蚀低合金钢10CrCuSiV锈层分析研究报告

新型耐海水腐蚀低合金钢10CrCusiV,在大连海域全浸区挂片试验7a后的腐蚀率为0.23mm/a.通过金相、岩相、X射线衍射及扫描电镜、电子能谱等分析,都证明了10CrCuSiV钢的锈层致密,附着牢固,粘附性系数小;内锈层以Fe₃O₄为主,有良好保护性;而合金元素在蚀坑内的富集有效地抑制了局部腐蚀作用.     

Q235碳钢在西沙大气暴晒的锈层特征

在西沙群岛高温、高湿的海洋大气环境下对Q235碳钢进行了3个月的暴晒实验,利用电子探针、激光拉曼等观察分析了暴晒后样品的锈层特征.结果表明:Q235碳钢暴晒1个月后迅速形成较厚的锈层,锈层疏松多孔,多裂纹;当暴晒3个月时,锈层却明显减薄.Q235碳钢在西沙暴晒1个月后形成的外层腐蚀产物主要是γ-FeOOH、β-FeOOH、α-FeOOH及少量Fe₃O₄等,而锈层内部主要为Fe₃O₄、γ-Fe₂O₃等铁的氧化物.暴晒3个月后,疏松锈层的内部电解液蒸发加剧,内层还原后的锈层重新被氧化,生成较多的FeOOH,同时部分γ-FeOOH转化成为α-FeOOH.Q235碳钢在西沙大气环境下的暴晒过程(也就是锈层的氧化还原反应的交替过程)中,钢基体不断地被腐蚀.     

耐候钢表面保护性锈层的力学性能

通过连续加载超显微硬度压痕试验测试了耐候钢表面保护性锈层的承载能力.试验结果表明,延长挂片时间,可使耐候钢表面致密锈层开裂的临界压载增大,断裂韧性改善,锈层的承载能力提高,抵抗裂纹扩展的能力增强.     

Q355耐候钢加速腐蚀锈层演变规律研究

利用加速腐蚀试验,对Q345低合金钢和Q355耐候钢不同时间腐蚀后试样的锈层形貌及腐蚀产物进行对比分析,结果表明:两种试验钢的锈层均主要由α-Fe OOH、γ-Fe OOH和Fe2O3组成,随着腐蚀时间延长,α-Fe OOH、γ-Fe OOH含量逐渐增加,Fe2O3含量逐渐降低,锈层颜色呈现黑色→红色→黄棕色的变化规律。与低合金钢相比,耐候钢锈层中α-Fe OOH含量在不同时间腐蚀后均比低合金试验钢高,并较早由不连续块/片状逐渐长大发展成连续/致密的针状或片状物,孔洞少且较致密平整,附着力强,不易脱落。耐候钢的腐蚀率明显低于低合金钢,且在试验涉及的腐蚀时间内变化不大。     

Effect of Cr on Characteristic of Rust Layer Formed on Low Alloy Steel in Flow-accelerated Corrosion Environment

The flow-accelerated corrosion experiments were carried out to research the effect of Cr on the rust layers formed on the carbon steel and Cr-containing steel,as well as the structure of rust layer of the two experimental steels.The influence of Cr on the flow-accelerated corrosion resistance and the corrosion morphology of inner rust layer formed on the Cr-containing steel were studied by the methods of polarization curves,scanning electron microscope,transmission electron microscope,and X-ray photoelectron spectroscope.The distribution of Cr and its form of existence in the inner rust layer were analyzed.The results show that corroded mass loss of Cr-containing steel is lower than that of carbon steel and its inner rust layer is compact.Cr exists in the form of Fe2CrO4 and is enriched in the inner rust layer.This concentration could make the inner rust layer exhibit the tendency of amorphous.This phenomenon is related to fine Fe2CrO4.The inner rust layer becomes more compact because of the formation of fine Fe2CrO4,and the protectiveness of inner rust layer could be improved remarkably.     

无取向硅钢磁性能检测的两种方法对比

文章主要是对重量为1 kg(28片)的无取向硅钢试样与重量为0.5 kg(16片)的无取向硅钢试样进行对比试验。经过数据的对比后,可以得到重量为0.5 kg试样与重量为1 kg试样的检测方法在检测数据的准确性上是一致的,而且重量为0.5 kg的试样在质量管控上更加有效,在时间和材料消耗上都有节省,同时可以降低人员的劳动强度。     

Performance of Active and Passive Methods for Measuring Low-Frequency Surface Wave Dispersion Curves

This paper examines the consistency between surface wave dispersion curves measured at wavelengths of up to 600 m using active and passive methods at sites in the Mississippi Embayment. Large-diameter (200 m) circular receiver arrays were deployed at five deep soil sites located in Tennessee, Arkansas, and Missouri to record ambient ground vibrations at low frequencies. Measurements were performed at the same locations using linear receiver arrays and actively generated low-frequency energy using the recently developed Network for Earthquake Engineering Simulation (NEES) field vibrator (termed Liquidator). Characteristics of the ambient wavefield measured at the five sites in the Mississippi Embayment are presented along with comparisons between the surface wave dispersion curves obtained from the active and passive measurements at each site. The ambient wavefield measurements exhibited peak levels in the frequency range of 1–5 Hz. Surface wave dispersion curves developed from frequency-wavenumber (f-k) processing of the active and passive methods were in good agreement at four of the sites, with phase velocities from the passive measurements within 5–10 % of the active-source measurements out to wavelengths of about 550 m. Improved comparisons were obtained at the fifth site by applying high-resolution f-k processing.     

镀锌卷白锈浅析

在通过分析白锈产生原因及对从镀锌钢卷下线到客户各流通环节引起白锈异议的情况分析,指出了白锈发生的源头,通过控制影响因素,降低白锈异议。     

Structure and Electrochemical Behavior of the Rust on 690 MPa Grade Construction Steel in a Simulated Industrial Atmosphere

Metallurgical and Materials Transactions A - In this article, the rusting evolution of 690 MPa grade multifunctional construction structural steel was investigated under a simulated industrial...     

Measuring Performance for Building Maintenance Providers

A building maintenance scheme was introduced in Hong Kong Housing Authority in January 2006 which employed contractors to provide inspection inside the public housing tenants’ units and arranged necessary repair works. This study aims to assess the contractor service quality performance. A method of assessment is devised based on the SERVQUAL approach to measure the public housing owner’s frontline representatives’ expectations and perceptions of the contractors’ performance. The outcome indicates that the deficiencies of service quality variables are related to the willingness of the contractors to provide prompt responses to requests from the tenants or the owner’s frontline representatives, and the availability of sufficient resources to perform the promised service dependably and accurately in terms of time, cost, and quality. The outcome of this study helps to identify the weaknesses of the contractors and allows them to properly allocate resources to those urgently needed variables. The implications from this study are considered and recommendations for industrial practices and further research are made.