硅酸盐胶黏剂在高温磨蚀条件下的退化行为

Degradation of Silicate Adhesive Under High Temperature andTribo-Corrosion Condition

本工作设计并制备了含K^+、Na^+的液相硅酸盐胶泥,通过模拟高温磨蚀的特殊工况,采用微观结构扫描、XRD物相测试、力学压缩试验及ANSYS受力分析研究了该胶泥的退化行为。结果表明:在高温磨损工况下(温度200℃,流速2 m/s),试样表面形成胶凝状的难溶性混合盐,强度退化率为12%;在高温腐蚀(200℃,31%盐酸溶液)及高温腐蚀磨损(200℃,31%盐酸溶液、流速2 m/s)条件下,胶体表面发生化学腐蚀,生成可溶解性盐及氯化物,未形成有效的保护膜,其强度退化率分别为31%与39%。在本试验条件下,硅酸盐胶黏剂在高温磨蚀条件下的损伤主要受腐蚀因素控制。

The silicate adhesive with liquid phase containing K+,Na+was designed and prepared,and the properties were studied under special high temperature and tribo-corrosion working conditions.The degradation behavior of the adhesive was evaluated and analyzed through scanning electron microscopic,X-ray diffraction(XRD)test,mechanical compression test and finite element modeling.The results showed that the insoluble mixed-salt formed on the surface of the adhesive under high temperature and abrasion condition(with a temperature of 200℃and flow rate of 2 m/s).The degradation rate of strength was about 12%.Both under high temperature corrosion condition(200℃,solution with 31%hydrochloric acid)and high temperature tribo-corrosion condition(200℃,solution with 31%hydrochloric acid and flow rate of 2 m/s),the chemical reaction occurred on the surface of adhesive and the soluble salt with chloride was generated,which cannot form protective film.The degradation rates of strength are 31%and 39%respectively under above two conditions.Under high temperature and tribo-corrosion,the damage process of the silicate adhesive was mainly controlled by corrosion factor.