钼酸盐钝化液的研制

研制了一种热镀锌钢板的无铬钝化液,采用在钼酸盐和磷酸钝化液中添加各种化学试剂,以提高钝化膜的耐腐蚀性能。采用附着力试验、醋酸铅加速腐蚀试验、中性盐雾试验和电化学试验分析无铬钝化膜的耐腐蚀性能。结果表明,此无铬钝化膜具有成本低廉且具有良好的抗白绣能力,符合欧洲RoHS指令,可以用来代替铬酸钝化。     

热镀锌钢板无铬钝化膜耐腐蚀性研究

针对某冷轧厂投产初期生产的无铬钝化热镀锌产品耐盐雾腐蚀性差的问题,从分析影响无铬钝化镀锌产品耐腐蚀性能的因素入手,优化带钢表面粗糙度、无铬钝化膜膜重、涂覆辊硬度等工艺,使热镀锌钢板无铬钝化膜的耐蚀性得到明显改善,72 h中性盐雾试验腐蚀面积≤5%的合格率达到94%以上。     

武钢连续热镀锌机组采用WXD钝化工艺的可行性

一、前言镀锌产品生产中,一般都要对锌层表面进行钝化处理,以便提高锌层表面的耐蚀性能,使它对外界腐蚀介质的影响不敏感。为此,一般采用化学钝化剂(即强氧化剂)来处理锌层表面,使它生成一层耐蚀的钝化膜。武钢连续热镀锌机组上引进的西德“蒂森钝化工艺”,即采用铬酐作钝化剂来进行锌层表面处理。由于所生成的钝化膜不均匀,其耐蚀性不高(抗盐雾腐蚀寿命小于24     

镀锌层表面新型环保钝化膜的耐腐蚀性能

 通过扫描电镜、辉光光谱、电化学测试、盐雾实验及湿热实验等手段探讨了用于钢板镀锌层表面A、B两种新型环保钝化膜的微观状态和耐腐蚀性能。结果表明：A型环保钝化膜的耐腐蚀性能明显优于传统铬酸盐钝化膜;B型环保钝化膜的耐腐蚀性能略低于传统铬酸盐钝化膜;并讨论了A型环保钝化膜耐腐蚀性能优异的原因。     

409L铁素体不锈钢的表面钝化膜性能

用辉光光谱仪(GDS)、扫描电镜(SEM)和X-射线光电子能谱仪(XPS)分析了经20%HNO₃、58℃0～60 min钝化的409L冷轧不锈钢(%:0.017C、11.50Cr、0.17Ti)表面钝化膜的性能,并通过盐雾试验得出钝化膜厚度对耐蚀性的影响。结果表明,当钝化时间为10 min时,钝化膜厚度达到最大值48 nm;当钝化时间为3 min时,钝化膜厚度为40 nm,试样表面氮化物完全被钝化膜覆盖,膜中Cr的氧化物含量最多,耐蚀性最好。     

铝合金有机无机复合无铬钝化膜的耐腐蚀性能实验设计

本文在研究铝合金有机无机复合无铬钝化膜的耐腐蚀性能,提出进行电化学性能测试、表面性能测试、硫酸铜点滴实验、中性盐雾试验,研究硅烷氟锆酸盐钝化工艺,从实验研究中能够看出无铬钝化膜具有较为优异的腐蚀性能。     

钝化处理后热镀锌板折边发黑的原因分析及解决方法

钝化处理后的热镀锌板在深冲时折边区域出现黑色痕迹,通过与正常产品样板进行表面铬含量、摩擦系数及摩擦区域的SEM微观形貌对比,黑色痕迹是由于钝化膜偏厚,在冲压时磨损导致。结合产线实际,对钝化液浓度、蘸料辊与涂覆辊的压力、涂覆辊与带钢间的压力等因素进行调整,对比钝化膜厚度和盐雾效果,优化钝化工艺,将钝化膜厚度控制在36～40 mg/m~2,即可满足客户需求。     

镀锡板表面铬酸盐钝化膜的研究

研究了镀锡板表面铬酸盐钝化中的含铬量与铬酸盐浓度、温度、阴极钝化电流密度、钝化电量的关系,用增加了钝化膜含铬量的低锡量镀锡板与Ｅ４、Ｅ２的常规镀锡板进行了盐雾对比试验。孔隙率对比试验。并且用增加了钝化膜含铬量的低锡量镀锡板进行了涂附性能和焊接性能试验。用ＸＰＳ对钝化膜的组成进行了分析。     

热镀锌卷板表面细线状条痕缺陷研究与对策

采用盐雾试验和扫描电镜(SEM)对热镀锌卷表面的密集细线状条痕缺陷进行分析。结果表明,密集细线状条痕缺陷产生于钝化辊。通过对钝化辊的磨削质量进行严格把关,钝化辊辊期合理安排,可以消除密集细线状条痕缺陷。     

环保型表面处理镁合金耐蚀性及疲劳性能研究进展

总结了近年来几种环保型表面处理镁合金耐蚀性和疲劳性能的研究结果,归纳了磷酸盐、高锰酸盐、锡酸盐、植酸盐、锆酸盐、稀土金属盐等化学转化膜及阳极氧化对镁合金耐蚀性和疲劳性能的影响,展望了环保型表面处理镁合金技术的前景。     

热镀锌无铬耐指纹钢板涂装前处理工艺探讨

在一定生产工艺条件下,通过试验揭示了热镀锌无铬耐指纹产品涂装前处理工艺的变化对耐指纹皮膜的影响规律,进一步研究膜重对产品应用性能（包括导电性、耐摩擦性、耐指纹性、耐热性、涂装性及耐蚀性等）的影响规律,并提供相关的技术参考。结果表明,经前处理后,耐指纹皮膜质量有一定的损失,而膜重是影响产品最终应用性能决定性的因素,将钢板出厂膜重控制在1.0～1.3g/m2范围内,可生产出综合性能优良的热镀锌耐指纹产品。     

Ti-IF钢热镀锌钢板力学性能控制

在设计生产DQ级以下产品的热镀锌机组上进行了Ti-IF钢热镀锌试验,研究了RTH带钢温度和光整对Ti-IF钢热镀锌板组织、织构和力学性能的影响.试验结果表明,以超低碳Ti-IF钢为基础,保证合适的过剩钛,采用合适的工艺制度,可以生产力学性能优良的正常锌花热镀锌钢板,其屈服强度在150 MPa左右,r、n平均值分别达到2.5和0.25.但是,经光整后,屈服强度明显提高,n值明显降低,且成品晶粒尺寸较粗时,光整后的n值较低.根据试验结果,提出了根据热镀锌板表面状态和用户使用条件采用不同的工艺控制技术路线来保证Ti-IF热镀锌板力学性能的策略.     

Post treatment of silane and cerium salt as chromate replacers on galvanized steel

A complex film on hot-dip galvanized steel sheet (HDG) was prepared by immersing the sheet in 0.1wt.% Ce(NO3)3 solution and 5vol.% silane solution in turn. The corrosion protection of the complex film was evaluated by potentiodynamic linear polarization(LPR), electrochemical impendence spectra (EIS) and natural salt spray (NSS) tests and compared with that of single cerium film and silane film. The results showed that, the presence of these films on the zinc coating hindered corrosion reaction by reducing the rate of both anodic and cathodic reaction in the corrosion process, and the corrosion protection of the complex film was much better than that of single cerium film or silane film and closed to that of chromate film, because the polarization resistance Rp and electrochemical impendence were increased markedly. Microstructure and chemical composition of these pretreated films were also investigated by scanning electron microscopy (SEM) and AES.     

Surface and Coating Analysis of Press‐Hardened Hot‐Dip Galvanized Steel Sheet

The use of continuous galvanized steel sheet as feedstock material for press hardening leads to components of very high strength levels with classical cathodic corrosion protection. The present work provides an insight into this technology with special focus on surface oxidation and intermetallic phase formation during the austenisation process. For that reason hot dipped galvanized 22MnB5 steel sheets, with a blank thickness of 1.5 mm and an average coating weight of 70 g m^?2, were annealed in a temperature range of 400–900°C in steps of 50°C without soaking before quenching in water. Surface and cross‐cuts were analyzed by SEM, EDX, and XRD to illustrate the phase formation and the surface changes during thermal treatment. Corrosion behavior was also studied based on electrochemical investigations and an accelerated, cyclic, automotive corrosion tests called VDA, which is a mixture of salt spray test and alternating climate test. It was found that austenisation of galvanized steel sheet causes a significant change of the coating. The generated coating still offers cathodic protection for the steel substrate and has higher corrosion resistance than standard galvanized steel sheet. Surface oxidation also occurs during the press hardening process leading to a surface covered with successively arranged layers of Al₂O₃ and ZnO, containing also further oxidized alloying elements.     

热镀锌液中Al含量及工艺对TRIP钢表面质量的影响

通过对TRIP590钢进行不同Al含量锌液热镀锌对比试验,研究了锌液中不同Al含量及热镀锌工艺对TRIP钢镀层性能的影响。试验结果表明,镀锌液中加入5%Al,均热退火温度800℃,可明显提高TRIP钢的镀层质量,改善热镀TRIP钢的抗腐蚀性能。     

连续热浸镀铝硅钢板镀层微观结构研究

 热浸镀铝硅钢板具有优良的耐热性、耐腐蚀性、耐高温氧化性,目的是研究铝硅镀层钢板的镀层微观结构和性能。利用热镀锌模拟器在实验室条件下制备了热浸镀铝硅镀层钢板,通过扫描电镜、电子探针对镀层的微观组织结构、镀层中元素的平面分布进行了观察,利用X-射线研究了铝硅镀层的物相组成,利用盐雾试验研究了镀层钢板的耐腐蚀性能。结果表明,铝硅镀层由占主要富铝的树枝晶、树枝晶间的铝硅二元合金、铁铝界面层及分布于基体中的块状相组成,镀层组织均匀,结合较好,耐蚀性优良。     

热镀锌退火过程中的温度控制策略

热镀锌退火过程对热镀锌板力学性能有着重要的影响.制定合理的退火温度制度,并精确控制板温,成为实现热镀锌板精准退火过程的核心问题.分析了退火工艺对热镀锌板性能的影响,针对现有退火工艺制定方法的不足提出了基于数据驱动的退火工艺制定方法,该方法能够实现热镀锌板退火工艺的持续优化.同时系统地综述了目前基于模型的热镀锌退火过程板温控制策略,针对热镀锌退火过程特点,提出了具有高适用性的数据与物理模型相混合的热镀锌退火过程温度控制方法,能够实现热镀锌板的精准热处理.     

New types of coating systems for steel sheets by high‐rate evaporation in combination with plasma processes

High‐rate evaporation in combination with plasma processes is a promising approach to obtain new types of steel sheet coating with improved corrosion resistance and application properties. To estimate the potential for the application of PVD‐coatings (physical vapour deposition) different coating systems for steel sheet as well as for hot‐dip or electro‐galvanized steel sheet were designed. The samples were produced on a laboratory scale using PVD processes with very high deposition rates (in the order of 1 μm s^‐1) as well as high‐power plasma processes for the pre‐treatment. The relationship between the composition, microstructure and properties of the coating systems, in particular concerning corrosion protection, abrasion during forming, phosphating and paint adhesion, were studied. It was found that the corrosion resistance of galvanized steel sheets can be considerably improved by vapour deposition of metal or inorganic films with a thickness of several hundred nanometers. Investigations on vapour deposition of titanium and stainless steel coatings on steel sheets, for applications in a severely corrosive environment, showed that the corrosion resistance in relation to the coating thickness can be significantly enhanced by means of plasma activation during the vapour deposition process. Finally, an outlook on possible industrial applications including an estimation of the process costs will be presented. For certain coating systems the results look promising. Consequently, these particular coating systems will be investigated in more detail by means of using a large‐scale in‐line deposition plant for metallic strips and sheets.     

光整对热镀锌IF钢板力学性能的影响

在生产DQ级以下的热镀锌机组上进行了Ti—IF钢热镀锌实验,研究了光整对Ti-IF钢热镀锌板力学性能的影响。实验结果表明,在正常情况下,热镀锌钢板其屈服强度在150MPa左右,r,n平均值分别为2．5和0．25。但是光整后,屈服强度明显提高,n值明显降低。实验结果,提出了根据用户的不同要求,采用不同的工艺路线来保证Ti—IF钢的力学性能。并且对热镀锌Ti—IF钢力学性能的控制问题进行了一些讨论。