55%Al-Zn池中底渣的形成与控制

由于具有优良的性能,近年来Galvalume镀层的发展非常迅速,并有取代纯锌镀层的趋势。但在Galvalume的生产线上普遍存在严重影响镀层质量和生产效率的底渣问题。目前对于55％Al-Zn池中的底渣问题还没有一个较好的解决办法,该文针对55％Al-Zn池中底渣的形成机理、影响因素及相应的处理方法进行了探讨,对Galvalume生产过程中的底渣控制具有一定的参考意义。     

55%Al—Zn镀层钢板的发展与应用

主要介绍世界各国 55% Al-Zn镀层钢板近年来的发展与应用 ;通过对国内市场的调查和分析 ,展望了我国 55% Al-Zn镀层钢板的发展前景。     

Al—Zn合金阻尼性能研究

本文采用自由梁和悬臂梁声频弯曲共振自由衰减法测量Al-Zn合金的衰减系数δ,配备微机系统采集和处理数据,计算损耗因子θ~(-1)。测量结果表明Al-Zn共折合金的损耗因子在150℃以下随温度升高而增大;随频率降低而增大;在小振幅(10~(-6)～10~(-4)m)范围内随振幅变化不明显。并从合金组织结构因素分析讨论了Al-Zn共折合金热处理后的最佳阻尼性能和机械性能。     

锌基铝稀土镁热镀合金镀层

ZnAlREMg热镀合金是继Galfan合金之后出现的一种新型镀层材料,其镀层表面质量、抗蚀性能均优于目前应用的纯锌镀层和ZnAlPb合金镀层。与单一的锌镀层相比,ZnAlREMg合金镀层厚度减薄约1/3,镀层上锌量降低20％左右,镀层抗蚀性提高1～2倍。采用氯化物溶剂助镀,ZnAlREMg 合金可在纯锌的热镀线上浸镀。     

无结晶形成Zn-Al-RE机械镀合金镀层研究

采用机械镀方法在钢铁制品表面上形成锌基铝-稀土合金镀层,试图以无结晶方式形成镀层主体.试验发现,镀层主体的构成是金属粉颗粒混杂的镶嵌体,具有相应的金属特性和对铁基的电化学保护性,镀层形成过程中镀层主体的形成可以不发生结晶现象.复合稀土金属添加剂能细化金属粉藻团,提高金属粉和基体材料表面的活性和润湿性,加快了吸附过程,从而使金属粉的利用率得到提高,镀层的外观、致密性、结合强度、耐腐蚀性能等得到改善.在复合稀土金属添加剂加入量为1%～3%时,机械镀Zn-Al-RE合金镀层的致密度、电化学特性和耐腐蚀性能优于机械镀锌层,并在加入量1%处各项性能指标出现最佳值.     

稳定剂对镍磷镀液性能及镀层耐蚀性能的影响

研了化学镀镍液中不同稳定剂对镀液的性能及镀层耐腐蚀性能的影响。发现碘化钾作稳定剂的镀液稳定性及镀层耐腐蚀性能较好，镀液寿命较长，镀层缺陷少，孔隙率低；铅离子作稳定剂镀液稳定性好，但镀液寿命短，耐腐蚀性能较差。硫脲做稳定剂镀液稳定性差。镀液寿命短，镀层胞状颗粒粗大，缺陷多，耐蚀性能差。得出了镀层孔隙率及表面形貌结构是影响镀层耐蚀性能的主要因素之一，镀层缺陷越少。镀层的耐蚀性能就越好。     

喷射沉积的影响因素及沉积体性能控制

详细分析了喷射沉积的影响因素,归纳了建立数学模型、制定统一工艺标准和实行实时控制3种方式来控制沉积体性能。     

WC复合镀层耐腐蚀性能研究

采用复合电沉积工艺制备了Ni-WC复合镀层,通过SEM、EDS和金相显微镜对其表面和断面形貌进行了观察,并借助电化学手段研究了Ni-WC复合镀层在3.5%NaCl腐蚀液中耐蚀性能。结果表明:WC微粒随着电沉积过程逐步埋入复合镀层并均匀分布,镀层与基体间结合良好,在3.5%NaCl腐蚀液中,复合镀层比纯镍镀层相比,腐蚀电位正移而腐蚀电流减少,耐腐蚀能力得到提高。     

抑制层和ξ-FeZn13相对热镀锌双相钢镀层附着性能的影响

通过对比研究3种不同双相钢变形下的镀层和抑制层形貌,寻找影响镀层附着力的因素.试验研究表明,Fe-Al颗粒细小且排列紧密时,镀层的附着性强;Fe-Al颗粒不连续紧密时,镀层附着力大大减弱.双相钢镀层变形时,含有ξ-FeZn13颗粒的镀层容易出现裂纹,且裂纹多数在ξ-FeZn13颗粒集中的区域.ξ-FeZn13颗粒能降低镀层的附着性能,降低镀层的质量.     

桥梁缆索用高强度Zn-10%Al-RE合金镀层钢丝耐蚀性能研究与应用

对桥梁缆索用高强度纯锌镀层、Zn-5%Al-RE合金镀层和Zn-10%Al-RE合金镀层钢丝的镀层组织及耐蚀性能进行了对比研究。研究结果表明,Zn-10%Al-RE合金镀层由于Al含量的提高,镀层中Zn-Al共晶相的比例较Zn-5%Al-RE合金镀层更大,且具有更多耐腐蚀的富铝相,说明其具有更好的耐蚀性能。从电化学分析和中性盐雾试验结果来看,纯锌镀层的自腐蚀电流密度约为Zn-10%Al-RE合金镀层的3倍,不同时间下的中性盐雾腐蚀失重为纯锌镀层的3.9～5.7倍,说明其在同一腐蚀环境中的耐蚀性能至少能够达到纯锌镀层的3倍以上。     

热镀用锌铋多元合金的研制

介绍了实验室条件下配制锌铋多元合金的方法和工艺,模拟热镀锌操作工艺进行了锌铋多元合金的热镀试验,并对镀层进行了盐雾腐蚀试验和金相组织检测。确定了锌铋多元合金的最佳配方。     

Influence of Surface Roughness of Galvanized Steel Sheet on Self-lubricated Coating

Three different thicknesses of self-lubricated coatings were prepared on galvanized steel sheets with different surface roughness(Ra).Performances of the coatings were evaluated by various laboratory tests.Scanning electron microscopy(SEM),atomic force microscope(AFM),neutral salt spraying test(NSST),reciprocating friction and wear test were taken in order to characterize the coatings.Results show that the self-lubricated coating has good corrosion resistance and lubricating property.In 0.857-1.629μm of Ravalue,the relationship between friction coefficients of the self-lubricated steel sheets and the surface roughness of the galvanized steel sheets likes a parabolic curve,and has a peak value of friction coefficient in certain range of Ra.Affected by the hereditary surface topography of the galvanized steel sheet,dents on the surface of self-lubricated steel become deeper and larger with the increase of the surface roughness of the galvanized steel sheets.The influence of the surface roughness of the galvanized steel sheet on the corrosion resistance of the self-lubricated coating steel is similar to that on friction coefficient of self-lubricated coatings,like a parabolic curve.     

Structure and Corrosion Resistance of Microarc Oxidation Coatings on AZ91D Magnesium Alloy

Magnesium alloys are widely used as shells of 3C (computer, mobile phone and consumer electronics) equipments for its impressive mechanical and physical properties, such as low density, good resistance to electromagnetic radiation, suitable for high pressure diecasting and easily recycling, etc. But poor corrosion resistance confines its extensively application. In this paper, protective coatings was successfully prepared on AZ91D magnesium alloys by micro-arc oxidation (MAO) and painting process. Microstructures and phases of MAO coatings were invesgated with scanning electron microscope (SEM) and X-Ray diffractometer. Mechanical properties of MAO coating, such as adhesive force and corrosion resistance, were also tested. Results showed that MAO coatings were a good base for painting process. MAO coatings with paint have good adhesive properties to base metal and excellent corrosion resistance. Micro-arc oxidation with painting process is a good kind of surface treatment to improve the corrosion resistance of mobile phone shell made of AZ91D magnesium alloys.     

钼镧合金表面FeCrAl涂层耐腐蚀性能

采用非平衡磁控溅射工艺在Mo–La合金表面沉积FeCrAl涂层,研究所制备涂层的耐腐蚀性及涂层的腐蚀机理。结果表明：FeCrAl涂层样品在360℃、18.6 MPa、纯水的高压釜中腐蚀72 h,平均腐蚀速率为3.8 mg·dm_?²,低于同条件下锆合金以及未沉积涂层的钼镧合金的腐蚀速率,且涂层中的Al与外界环境介质中的氧发生反应,在涂层表面形成致密的Al₂O₃薄膜,在一定程度上减缓了涂层的腐蚀速度,有效保护了基体材料。FeCrAl涂层样品在1200℃、0.1 MPa的高温水蒸气环境下腐蚀8 h,Al₂O₃氧化膜厚度在4.0μm左右,涂层维持保护效果,钼镧合金基体未暴露在腐蚀环境中;经淬火后,Al₂O₃氧化膜厚度减小至2.5μm左右,涂层依旧维持结构完整性,没有出现贯穿性脱落,满足Mo–La合金表面耐腐蚀性的使用要求。     

热喷涂制备非晶合金涂层性能的研究进展

首先介绍了非晶合金的理论基础,然后从耐磨性和耐蚀性两个方面入手,详细地阐述了国内外对于热喷涂非晶合金涂层性能研究进展情况,并系统地总结了非金合金涂层在耐磨性和耐蚀性上的本质联系和根本矛盾,最后指出热喷涂非晶合金涂层性能研究上的局限性,提出三点问题:对于非晶合金基础理论的研究还处在起步阶段、热喷涂制备非晶合金涂层的合金体系种类少、制备非晶合金涂层的热喷涂技术有待开发,并针对以上三点问题提出热喷涂制备非晶合金涂层性能研究的未来发展方向。      

稀土和铬对铁基自熔合金涂层耐蚀性的影响

本研究着眼于考察稀土和合金成分对铁基自熔合金涂层的耐蚀性的影响,对不同成分的合金涂层进行了三酸一盐的浸蚀试验。结果表明在硫酸和硝酸溶液中,稀土的添加对合金涂层的耐蚀性有利,但在盐酸和氯化钠溶液中,稀土的添加对合金涂层耐蚀性无益。铬含量高的铁基自熔合金涂层在硝酸溶液中有优良的耐蚀性,但在硫酸和盐酸中的耐蚀性不如铬含量低的铁基自熔合金涂层。文中分析了不同合金在试验中的不同表现的原因,进而为铁基自熔合金的进一步工业应用提供有用的信息。     

Corrosion Resistance of Different Metallic Coatings on Press‐Hardened Steels for Automotive

The corrosion resistance of laboratory press‐hardened components in aluminized, galvanized or galvannealed boron steels was evaluated through VDA 621‐415 cyclic test for the automotive industry. 22MnB5 uncoated steel for hot stamping and standard galvanized steel for cold forming were also included as references. Corrosion resistance after painting (cosmetic corrosion) was quantified by measuring the delamination of electro‐deposited paint from scribed panels. The rusting on their edges was used for determining the cut‐edge corrosion resistance. The corrosion resistance on unpainted deformed panels (perforating corrosion) was quantified by mass losses and pit depth measurements. Zinc‐coated boron steels were found to be more resistant to cosmetic corrosion than the other materials, and slightly more resistant to cut‐edge corrosion than the aluminized one. Red rust apparition could not be avoided due to the high iron content in all these hot‐stamped coatings. The three coated boron steels showed similar performances in terms of resistance to perforation. Aluminized boron steel presents the advantage of being less sensitive to hot‐stamping process deviation. Its robustness has been proved for many years on cars.     

钛合金表面微弧氧化耐磨和耐蚀膜层的研究进展

微弧氧化是一种直接在有色金属或其合金表面原位生成陶瓷膜的新技术,利用该技术可在钛合金表面生成耐磨和耐蚀性能优良的膜层。介绍了微弧氧化技术及其特点、钛合金表面微弧氧化耐磨和耐蚀膜层的研究进展,并指出了钛合金表面微弧氧化耐磨和耐蚀膜层的应用前景和今后膜层研究的发展方向。     

锌和镀锌钢的稀土表面改性

通过在Ce(NO_3)_3水溶液中对锌和电镀锌钢进行化学转化(钝化)处理,在试样表面形成了铈转化膜。利用电子探针显微分析(EPMA)、X射线光电子能谱(XPS)和X射线衍射(XRD)等研究了转化膜的形貌、成分和结构,探讨了锌表面铈转化膜的形成机理。在氯化钠溶液中测定了试样的腐蚀率、极化曲线和电化学交流阻抗谱(EIS)等腐蚀性能参量,并与未钝化和普通铬酸盐钝化试样的情况作了对比。结果表明,本实验得到的锌表面稀土转化膜主要是由CeO_2、Ce_2O_3和ZnO组成的复合氧化物膜,铈转化膜的存在阻碍了锌在电化学腐蚀过程中的阴极反应和阳极反应,导致电荷传递电阻增大,腐蚀率降低。在一定条件下,铈转化膜对锌和镀锌钢的肪蚀效果优于铬酸盐转化膜。     

Progress in Research on Vanadate-Based Coatings on Corrosion Resistance

Vanadate, usually used as the corrosion resistant inhibitor for the paint systems, is one of the substances that have been proposed as alternative to toxic chromate for the corrosion protection. In this paper, the possibility of vanadate passivating from its chemical properties was introduced firstly. Then, the progress and examples in research on vanadate conversion coatings on the corrosion resistance were summarized. And the substrates discussed here contained aluminum alloys, magnesium alloys and so on. Finally, the research tendency of vanadate-based coatings was discussed.