Al2O3-TiO2复相陶瓷涂层在动态LBE中的耐腐蚀行为

目的分析研究Al_2O_3-TiO_2复相陶瓷涂层在高温流动铅铋合金中的耐腐蚀行为。方法以纯Ti粉末、Fe Al粉末、CrFe粉末为原料制得复合粉末,在CLAM钢基材表面上采用热喷涂-激光原位合成复合工艺制备了Al_2O_3-TiO_2复相陶瓷涂层。试样在500℃,流速为0.3 m/s的液态铅铋合金中进行了时长1000 h的动态腐蚀实验,分别采用X射线衍射仪(XRD)、扫描电镜(SEM)、能谱仪(EDS)等分析测试手段对涂层试样在动态LBE中的耐腐蚀行为进行了研究表征。结果在CLAM钢基材表面制备的Al_2O_3-TiO_2复相陶瓷涂层表面形貌整体较腐蚀前仍保持完好,涂层物相成分保持稳定,截面分析显示铅铋合金在腐蚀过程在涂层中未见渗透;而没有涂层保护的CLAM钢基材在腐蚀后表面发生明显的氧化腐蚀现象,生成结构疏松的Fe3O4氧化层,铅铋合金在氧化层中有扩散分布。结论通过火焰热喷涂-激光原位合成复合工艺在CLAM钢表面制备得到的Al_2O_3-TiO_2复相陶瓷涂层在高温流动的铅铋合金腐蚀条件下组织结构稳定,具有良好的适用性,能有效地阻止高温流动铅铋合金对CLAM钢基体材料的腐蚀。

Anticorrosion Behavior of Al2O3-TiO2 Composite Ceramic Coating in Flowing LBE

The work aims to analyze anticorrosion behavior of Al2O3-TiO2 composite ceramic coating in flowing super LBE. Al2O3-TiO2 composite ceramic coating was prepared on the CLAM steel in oxyacetylene flame spraying-laser in-situ syn-thesis reaction compound technology with pure Ti, FeAl and CrFe powders. Anticorrosion behavior of the coating in flowing lead-bismuth eutectic (LBE) alloy was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) by carrying out 1000 h dynamic corrosion test to the sample in liquid LBE alloy at 500℃ with flow velocity of 0.3 m/s. The overall morphology of Al2O3-TiO2 composite ceramic coating surface remained intact com- pared to that before corrosion, coating phase composition remained stable, sectional analysis of lead-bismuth alloy was free from penetration in the coating during corrosion. The CLAM steel substrate without a protective coating was subject to obvious oxidation corrosion on the surface, loose structure of Fe3O4 oxide layer was generated, the lead-bismuth alloy was dispersed in the oxide layer. The Al2O3-TiO2 composite ceramic coating prepared in oxyacetylene flame spraying-laser in-situ reaction me-thod exhibits stable structure and excellent applicability, and can protect the substrate CLAM steel effectively in flowing lead-bismuth eutectic (LBE) alloy.