Corrosion characterization of ZrO2 and TiO2 ceramic coatings via air plasma spraying on 316 stainless steel in oxygenated sub- and supercritical water
Corrosion characterization of ZrO2 and TiO2 ceramic coatings via air plasma spraying on 316 stainless steel in oxygenated sub- and supercritical water
复制标题
通过空气等离子喷涂在含氧亚临界和超临界水中对 316 不锈钢进行 ZrO2 和 TiO2 陶瓷涂层的腐蚀表征
DOI：
10.1016/j.supflu.2019.104716
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发表时间：
2020-03-01
影响因子：
3.9
通讯作者：
Yang, Jianqiao
中科院分区：
文献类型：
--
作者：
Guo, Shuwei;Xu, Donghai;Yang, Jianqiao
合金316不锈钢是超临界水氧化装置的重要候选材料，但严重的腐蚀影响了其使用寿命和潜在应用。在这项工作中，ZrO 2和TiO 2涂层316 SS基板上的空气等离子喷涂，然后暴露在含氧亚和超临界水中。结果表明，在300 ~ 480 ℃、24 MPa、含氧量为3wt%、100 h的充氧亚超临界水中，该涂层可显著提高316不锈钢的耐蚀性。增加温度加速了测试的TiO 2和ZrO 2涂层样品的腐蚀。ZrO_2和TiO_2涂层可抑制316不锈钢基体中金属元素的向外扩散和氧的向内扩散。在480 ℃下，ZrO 2涂层样品的氧化膜由Cr2 O3、Fe 3 O 4、Fe 2 O3、NiFe 2 O 4和NiCr 2 O 4组成，而TiO 2涂层样品的氧化膜由Cr2 O3、Fe 3 O 4和Cr2 MoO 6组成。与ZrO 2涂层相比，TiO 2涂层对316不锈钢在含氧超临界水中的腐蚀具有更好的防护效果。TiO 2涂层样品的重量变化绝对值较低，腐蚀表面更均匀致密，更好地抑制了金属元素（尤其是Ni）的向外扩散和O的向内扩散。这表明，通过空气等离子喷涂在316不锈钢基体上的TiO 2涂层是一种有效的方法，以提高316不锈钢在测试的含氧超临界水的耐腐蚀性。(C)2019 Elsevier B. V.版权所有。
Alloy 316 stainless steel (SS) is an important candidate material for supercritical water oxidation facilities, but severe corrosion negatively affects its life-span and potential application. In this work, ZrO2 and TiO2 were coated on the 316 SS substrate by air plasma spraying and then exposed in oxygenated sub- and supercritical water. The results show that the coatings could greatly improve the corrosion resistance of 316 SS in oxygenated sub- and supercritical water in the range from 300 degrees C to 480 degrees C at 24 MPa with 3 wt% of oxygen content for 100 h. Increasing temperature accelerated the corrosion of tested TiO2- and ZrO2-coated samples. ZrO2 and TiO2 coatings could inhibit the outward diffusion of metal elements in the 316 SS substrate and the inward diffusion of oxygen. The oxide film of the ZrO2-coated sample was composed of Cr2O3, Fe3O4, Fe2O3, NiFe2O4 and NiCr2O4, while that of the TiO2-coated sample consisted of Cr2O3, Fe3O4 and Cr2MoO6 at 480 degrees C. Compared with the ZrO2 coating, the TiO2 coating exhibited better protective effects on reducing 316 SS corrosion in oxygenated supercritical water. The TiO2-coated sample led to lower absolute values of weight changes, more uniform and denser corrosion surface, and better inhibition on the outward diffusion of metal elements (especially Ni) and on the inward diffusion of O. This suggests that the TiO2 coating on the 316 SS substrate via air plasma spraying is an effective approach to improve 316 SS corrosion resistance in tested oxygenated supercritical water. (C) 2019 Elsevier B.V. All rights reserved.