Colloid Chemistry of Meso Structures and Reactivity of Steel Rusts

细观结构的胶体化学和钢锈的反应性

基本信息

批准号：
13450296
负责人：
ISHIKAWA Tatsuo
金额：
$ 9.73万
依托单位：
Osaka Kyoiku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2004
项目状态：
已结题

项目摘要

1)Synthesized rustsThe aim of this research project is to elucidate the mechanism s of corrosion and corrosion resistance of steels, such as weathering steels.. The structures and formation of the rusts artificially synthesized were irvestigated by various techniques. Including in a point of colloid chemistry. To clarify the role of alloying metals in corrosion resistance of weathering steels, the rusts are synthesized from aqueous Fe salt solutions containing various metal ions. The influences of metal ions strongly depend on the kinds of metal ions and rust components. Most of metals added to weathering steels interfered with the crystalization and particle growth of rusts. It was shown that alloying with more than two kinds of metals is shown to be effective. Especially, the addition of Ti(IV) effectively controlled the formation of β-FeOOH which is formed in Cl^- environment, indicating that the alloying with Ti effectively reduces the corrosion of steels in marine and coastal dist … More ricts. The influences of anions such as chloride, sulfate, and phosphate on the formation and structure of rusts were also studied to investigate the effects of corrosion environment. The formation of β-FeOOH was markedly influenced by the presence of the anions.2)Rusts of weathering steelsThe rusts formed in different situations were characterized by nitrogen adsorption. The rusts on weathering steels exposed in different environments for 17 years were examined by nitrogen adsorption. The specific surface area of the rusts determined by nitrogen adsorption decreased with decreasing the air-born salinity, which means that the rust particles grow with the increase of environmental Cl^- and the corrosion resistance of steels is lowered in marine and coastal districts. The corrosion rate of the steels was increased with decrease of specific surface area, that is, increase of particle size. This result reveals that the compactness of rust layers relating to corrosion resistance of steels is lowered by the particle growth of rusts. It was shown that the rust particles grow with the progress of corrosion. The similar results were obtained on t the rusts on various steels exposed to different situations. Consequently, the adsorption method is useful for characterization of rusts, expecially particle size of rusts which can not be estimated by the other techniques.3)Rusts of galvanized steelsThe steel galvanized by Zn-alloys is an important material in various industries. The corrosion resistance of the galvanized steels is still not thoroughly explored. The mechanism of high corrosion resistance of the galvanized steels was investigated by using the synthesized rusts of Zn-alloys. The rusts of Zn-Al alloys which are widely used for galvanizing steels were sheet particles of simonkoleite on adding a small amount of Al(III) in ZnCl_2 solution. The sheet particles form the compact rust layers by preferred orientation. This fact well accords to a high corrosion resistance of steels plated with Zn-Al alloy in Cl^- environment. It is known that the steels galvanized by Zn-Al-Mg alloys show a high corrosion resistance in the presence of Cl^-. The rusts of Zn-Al-Mg alloys prepared from solutions of Zn-Al-Mg salts were fine sheet particles and formed more compact layers than those of Zn-Al alloys as confirmed by measuring the permeability of air into the rust layers. Less

1）合成的生锈该研究项目的目的是阐明钢的腐蚀和耐腐蚀性的机制，例如风化钢。.人为地人为合成的生锈的结构和形成，通过各种技术进行了不利的评价。包括在胶体化学的点。为了阐明合金金属在风化钢的耐腐蚀性中的作用，锈蚀是从含有各种金属离子水性盐溶液中合成的。金属离子的影响很大程度上取决于金属离子和生锈成分。大多数金属添加到风化钢中，干扰了锈蚀的结晶和颗粒生长。结果表明，具有两种以上金属的合金被证明是有效的。尤其是，添加Ti（IV）有效地控制了在Cl^ - 环境中形成的β-feOOH的形成，表明使用Ti合金有效地降低了在海洋和沿海区中钢的腐蚀……更多。还研究了氯化物，硫酸盐和磷酸盐等阴离子对锈蚀形成和结构的影响，以研究腐蚀环境的影响。 β-feOOH的形成显着受阴离子的存在。通过氮补充吸附在不同的环境中暴露了17年。由氮确定的锈蚀表面积随着空气出生的盐度的降低而降低，这意味着锈蚀颗粒随环境Cl^的增加而生长，并且在海洋和沿海地区降低了钢的耐腐蚀性。钢的腐蚀速率随特定表面积的降低而增加，即粒径的增加。结果结果是，锈蚀颗粒的生长降低了与钢的耐腐蚀性有关的锈蚀层的紧凑性。结果表明，生锈颗粒随腐蚀的进展而生长。在暴露于不同情况的各种钢上的锈蚀上获得了类似的结果。因此，添加吸附方法对于锈蚀的表征很有用，锈蚀的极度粒径，无法通过其他技术估算。3）镀锌钢的锈蚀由Zn-Alloys镀锌的钢是各个行业的重要材料。镀锌钢的耐腐蚀性仍未得到彻底探索。使用Zn合金的合成锈蚀研究了镀锌钢的高腐蚀性的机理。广泛用于镀锌钢的Zn-Al合金的锈蚀是Simonkoleite的薄片颗粒，在ZNCL_2溶液中添加了少量Al（iii）。薄片颗粒通过首选方向形成紧凑的生锈层。根据Cl^ - 环境中用Zn-Al合金镀层的钢的高腐蚀性，这一事实很好。众所周知，在Cl^ - 存在下，由Zn-Al-Mg合金镀锌的钢表现出很高的耐腐蚀性。用Zn-Al-Mg盐溶液制备的Zn-Al-MG合金的锈蚀是细片颗粒，并且与Zn-Al合金的层相比，通过测量空气中的空气中的渗透性到锈层，形成更紧凑的层。较少的