ABSTRACT

The influence of silane pretreatment with five different volume ratios (100/0, 75/25, 50/50, 25/75, and 0/100) of 3-aminopropyltriethoxysilane (APTES)/tetraethylorthosilicate (TEOS) on microstructure and corrosion resistance of the hydrothermal synthesized zeolite coatings on the H13 steel substrates was investigated. The surface of the zeolite coatings on the 100/0, 75/25, and 50/50 mixture of the APTES/TEOS pretreated substrates was composed of intergrown rectangular particles. Additionally, pores were observed. A 25/75 mixture of APTES/TEOS pretreatment smoothed the edges and angles of zeolite particles with gel-like materials filled in the pores. In pure TEOS pretreatment, microcracks, and much gel-like materials were observed on the zeolite coating. The electrochemical test revealed that the zeolite coating on a 50/50 mixture of the APTES/TEOS pretreated substrate exhibited the highest corrosion resistance in 3.5 wt-% NaCl solution. This was because a 50/50 mixture of APTES/TEOS pretreatment advantageously promoted development of a dense and thick gel layer, which enhanced the intergrowth of zeolite particles.

摘要

3-氨丙基三乙氧基硅烷（APTES）/原硅酸四乙酯（TEOS）5种不同体积比（100/0、75/25、50/50、25/75和0/100）硅烷预处理对不锈钢微观结构和耐蚀性的影响研究了 H13 钢基材上的水热合成沸石涂层。APTES/TEOS 预处理基材的 100/0、75/25 和 50/50 混合物上的沸石涂层表面由共生的矩形颗粒组成。另外，观察到孔隙。APTES/TEOS 的 25/75 混合物预处理使沸石颗粒的边缘和角度变得平滑，并在孔中填充了凝胶状材料。在纯 TEOS 预处理中，在沸石涂层上观察到微裂纹和大量凝胶状物质。电化学测试表明，APTES/TEOS 预处理基材的 50/50 混合物上的沸石涂层在 3.5 wt-% NaCl 溶液中表现出最高的耐腐蚀性。这是因为 APTES/TEOS 预处理的 50/50 混合物有利地促进了致密且厚的凝胶层的形成，从而增强了沸石颗粒的共生。