耐氯化熔融盐相变储热材料腐蚀搪瓷涂层的制备与耐腐蚀机理

Preparation of enamel coating resistance to corrosion of chlorination molten salt phase change thermal storage material on the surface of heat-resistant stainless steel. Thermal stability, thermal fatigue resistance and corrosion resistance of ceramic coating were researched under both of the static and dynamic working conditions in high-temperature molten salt. A number of tests were carried out to presentthe ceramic coating formation mechanism, corrosion and failure mechanisms, including XRF, XRD, SEM, EPMA, HRTEM and Electrochemical method. The law of the impact of the physical and chemical properties of the coating and structure-effect relationship between the structure and properties from the properties of raw materials and preparation technology is revealed. Mathematical model would be established which could be used to simulated the distribution of stress between the coating and the substrate using ANSYS software. It could simulate the thermal storage process, and research the binding properties of the coating and the substrate, compared to the experimental results, analysis the applicability of the model.The purpose of this research project is to study the preparation and corrosion mechanism of anti-Corrosion enamel coating for chloride molten salt thermal storage material. The foundation of optimize the design of the enamel coating and large-scale applications storage for molten salt thermal storage materials is built.

在耐热不锈钢容器内表面制备一层耐高温氯化熔融盐相变储热材料腐蚀搪瓷涂层。重点研究在氯化熔融盐储热材料储/释热过程中强烈冷热循环及伴随的固-液相变的特殊工况条件下涂层材料的结合性、热稳定性、抗热震性及耐腐蚀性等化学物理特性，利用XRF（X射线荧光光谱分析）、XRD（X射线衍射）、SEM（扫描电子显微镜）、EPMA（电子探针显微分析）、HRTEM（高分辨透射电子显微镜）等测试技术及电化学手段，探索陶瓷涂层形成机理，耐腐蚀及失效机理。揭示陶瓷原料物性、制备工艺对涂层理化性能的影响规律及涂层结构与性能之间的构效关系。建立数学模型，利用ANSYS软件模拟储热过程中涂层与基材之间的应力分布，研究涂层与基材的结合性能，对比实验结果，分析模型的适用性。本项目研究的宗旨是研究耐氯化熔融盐相变储热材料腐蚀涂层的防腐蚀机理，为这种涂层的优化设计及高温氯化熔融盐相变储热材料的规模化存储应用奠定基础。

采用制备搪瓷釉浆、涂搪工艺在不锈钢表面制备了一层耐高温、耐氯化盐腐蚀搪瓷涂层。研究了氯化盐相变材料及目前主要的硝酸盐、碳酸盐相变材料对不锈钢的腐蚀性能，并研究了腐蚀动力学及腐蚀机理。获得了新型耐高温、耐氯化盐腐蚀搪瓷涂层配方组成及制备工艺。探索了新型搪瓷涂层对氯化盐相变材料及其它相变材料的耐腐蚀机理及失效机理。研究结果表明硝酸盐、碳酸盐、氯化盐相变储热材料对不锈钢具有腐蚀性，其中氯化盐腐蚀性最强。通过制备耐高温、耐腐蚀搪瓷涂层，可有效阻止无机盐相变储热材料的腐蚀性能。在涂层配方中添加Ni粉可有效解决涂层与不锈钢基体结合性差的问题，添加CeO2可有效解决涂层抗热震性能差，气孔率过高的问题。该涂层耐腐蚀性能较没有涂层的样品提高了76.10%，耐腐蚀效果明显。经过多次充放热循环后，涂层依然保持较好的微观结构和化学组成。该项目的研究成果大大拓展了无机盐相变储热材料的应用范围，同时拓展了储热领域，储热材料的选择范围。该项目研究成果可广泛应用于太阳能发电、风力发电、清洁能源供暖、工业用热以及电网调峰等领域。