冷轧钢表面磷化膜和硅烷膜的制备及性能研究

发布时间：2018-04-02 18:41

本文选题：冷轧钢　切入点：磷化膜　出处：《河南师范大学》2015年硕士论文

【摘要】：冷轧钢板因具有良好的性能,被广泛用于家电、汽车、工业设备和工程机械的制造中。但冷轧钢在应用过程中容易腐蚀,常需对其进行表面处理以延长使用寿命。在传统的表面处理技术中,磷化是一种重要的防腐蚀技术。常温快速磷化处理技术因克服了中高温磷化能耗高、成本大的特点,成为目前研究较为活跃的一种技术,受到普遍关注。随着社会的发展,节能环保已成为当前趋势,因此绿色环保的冷轧钢表面硅烷化处理技术成为一项有意义的研究。本文研究了在冷轧钢表面制备常温磷化膜和硅烷膜的工艺条件,以及添加稀土化合物对硅烷膜性能的改性作用。应用极化曲线、硫酸铜点滴试验测试制备膜层的耐腐蚀性能,盐水全浸泡测试对其与有机涂层间的结合力进行评价,扫描电子显微镜(SEM)对膜层的表面形貌进行表征。以硫酸铜点滴变色时间为指标,通过正交试验的方法确定了磷化液的最优配方。应用极化曲线和硫酸铜点滴实验的方法,通过单因素实验法测试了酸比、浸渍时间和磷化温度对磷化膜性能的影响并确定最佳工艺条件。在冷轧钢表面制备双-(γ-三乙氧基硅基丙基)四硫化物(商品名:Si-69)硅烷膜,采用极化曲线的方法,通过单因素实验法确定了Si-69溶液的配制方法。应用极化曲线和硫酸铜点滴实验的方法,通过单因素实验法测试浸泡时间、固化时间和固化温度对硅烷膜性能的影响,确定最佳工艺条件。将最佳工艺条件下制备的磷化膜和Si-69硅烷膜与空白冷轧钢进行性能对比。极化曲线和硫酸铜点滴试验结果显示:磷化膜和Si-69硅烷膜显著的增强了冷轧钢的耐腐蚀性能,但Si-69硅烷膜的耐蚀性能优于磷化膜。盐水全浸泡实验显示磷化膜和Si-69硅烷膜都增强了基体与有机涂层间的结合力,但Si-69硅烷膜对结合力的增强作用大于磷化膜。扫描电子显微镜(SEM)显示空白冷轧钢表面有划痕和坑洞;磷化膜表面呈现出凹凸不平并有少量空隙的片状结构;Si-69硅烷膜表面较磷化膜为平整,有一些线型凸起。为进一步提高硅烷膜的性能,探索了于Si-69溶液中添加稀土氯化物,在冷轧钢表面制备稀土改性硅烷膜的方法。选用CeCl3、YCl3、LaCl3作为添加物。采用极化曲线测试的方法,得到不同稀土氯化物的改性硅烷膜耐腐蚀性能最佳时添加稀土氯化物的量,此为稀土氯化物添加量的最优参数。用最优参数下制备的稀土改性硅烷膜与Si-69硅烷膜进行对比,极化曲线和硫酸铜点滴实验显示稀土改性硅烷膜耐腐蚀性能优于Si-69硅烷膜。盐水全浸泡实验显示,稀土改性硅烷膜对金属基体与有机涂层间的结合力增强作用大于Si-69硅烷膜。扫描电子显微镜(SEM)显示稀土改性硅烷膜的表面呈现均匀致密的结构,表面十分平整。
[Abstract]:Cold-rolled steel plate is widely used in the manufacture of household appliances, automobiles, industrial equipment and construction machinery because of its good performance.However, cold rolled steel is easy to corrode during application, and surface treatment is often needed to prolong its service life.Phosphating is an important anticorrosive technology in traditional surface treatment technology.Because of overcoming the characteristics of high energy consumption and high cost, the rapid phosphating technology at room temperature has become an active technology, which has been paid more attention to.With the development of society, energy saving and environmental protection have become the current trend, so the silane treatment technology of green cold rolled steel surface has become a meaningful research.In this paper, the process conditions of preparing phosphating film and silane film at room temperature on the surface of cold rolled steel were studied, and the modification effect of rare earth compound on the properties of silane film was also studied.The corrosion resistance of the film was tested by polarization curve and copper sulfate drop test. The adhesion between the film and the organic coating was evaluated by salt water immersion test. The surface morphology of the film was characterized by scanning electron microscope (SEM).The optimum formula of phosphating solution was determined by orthogonal test with copper sulfate drop discoloration time as index.The effects of acid ratio, impregnation time and phosphating temperature on the properties of phosphating film were determined by single factor experiment with polarization curve and copper sulfate drop test.Double (纬 -triethoxysilyl propyl) tetrasulfide (commercial name: W Si-69) silane film was prepared on the surface of cold-rolled steel. The preparation method of Si-69 solution was determined by polarization curve method and single factor experiment method.The effects of soaking time, curing time and curing temperature on the properties of silane film were measured by polarization curve and cupric sulfate drip test, and the optimum technological conditions were determined.The properties of phosphating film and Si-69 silane film prepared under the optimum technological conditions were compared with blank cold rolled steel.The results of polarization curve and copper sulfate drop test showed that the corrosion resistance of cold rolled steel was significantly enhanced by phosphating film and Si-69 silane film, but the corrosion resistance of Si-69 silane film was better than that of phosphating film.The salt water immersion experiments showed that both the phosphating film and the Si-69 silane film enhanced the adhesion between the substrate and the organic coating, but the enhancement effect of Si-69 silane film was greater than that of the phosphating film.Scanning electron microscopy (SEM) showed that there were scratches and holes on the blank cold-rolled steel surface, while the surface of the phosphating film was flat and had some linear protrusions.In order to further improve the properties of silane film, the method of preparing rare earth modified silane film on cold rolled steel surface by adding rare earth chloride in Si-69 solution was explored.CeCl _ 3 YCL _ 3 LaCl _ 3 was used as additive.The amount of rare earth chloride was obtained when the corrosion resistance of the modified silane film with different rare earth chlorides was the best by means of polarization curve test, which was the best parameter for adding rare earth chloride.The results of polarization curves and copper sulfate drop experiments show that the rare earth modified silane film has better corrosion resistance than that of Si-69 silane film.The results of saltwater immersion showed that the bonding strength of rare earth modified silane film was greater than that of Si-69 silane film.Scanning electron microscopy (SEM) showed that the surface of rare earth modified silane film was uniform and compact, and the surface was very smooth.
【学位授予单位】：河南师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG174.4

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