火焰喷涂玻璃涂层的耐蚀性研究

Study on the Corrosion Mechanism of Flame Sprayed Glass Coatings

研究了手工火焰喷涂玻璃涂层的腐蚀破坏机理。试验结果表明:在涂层冷却凝固过程中,由于残余应力的作用,形成了缺陷。在腐蚀过程的初期阶段,缺陷处形成腐蚀斑点。随着腐蚀过程的进行,腐蚀斑点逐渐扩大,最终导致整个涂层破坏。涂层破坏的主要原因是和腐蚀介质接触的底釉层首先被腐蚀掉,然后面釉层在残余应力的作用下断裂、塌陷,被分解为小碎片。该腐蚀特点是由玻璃涂层的结构、脆性和制备工艺决定的。可以通过优化喷涂工艺来改善涂层的耐蚀性。

The corrosion mechanism of flame sprayed glass coatings was studied in this paper. The results showed that the defects appeared on the surface of coating during the solidification due to residual stress, and some corrosion spots emerged with these defects at the early stage of corrosion. The corrosion spots became enlarge as the corrosion time was going. The main cause of the failure was that the bottom layer contacts with the corrosion solution was eroded first, which induced fracture of the upper layer under the action of residual stress and break into shivers. This corrosion characteristic was depend on the structure, brittleness and the preparation procedure of glass coatings. The corrosion resistance of the coatings could be improved by optimizing the spraying parameters.