文献类型：期刊文献

中文题名：TC4钛合金实海污损生物附着行为与腐蚀机理研究

英文题名：Fouling Organism Attachment Behavior and Corrosion Mechanism of Titanium Alloy in the Sea

作者：李友炽[1,2];邓培昌[2,3];王贵[1,2];胡杰珍[1,2];吴敬权[1,2]

机构：[1]广东海洋大学机械工程学院,广东湛江524088;[2]广东海洋大学湛江市海洋工程及装备腐蚀与防护重点实验室,广东湛江524088;[3]广东海洋大学化学与环境学院,广东湛江524088

年份：2024

卷号：53

期号：24

起止页码：110

中文期刊名：表面技术

外文期刊名：Surface Technology

收录：北大核心2023、CSTPCD、、EI(收录号：20250317706328)、Scopus、CSCD2023_2024、北大核心、CSCD

基金：广东省自然科学基金(2021A1515012129);湛江市科技计划项目(2022B01007);湛江市科技计划项目(2024B01068)。

语种：中文

中文关键词：TC4钛合金;电化学;污损生物;藤壶;附着腐蚀

外文关键词：TC4 titanium alloy;electrochemistry;fouling organism;barnacle;adhesion corrosion

中文摘要：目的研究TC4钛合金在实海中的生物腐蚀行为,以期为钛合金在海洋工程装备中的应用提供科学依据。方法TC4钛合金在广东湛江调顺岛实海中进行浸泡挂样,观察污损生物附着行为以及试样腐蚀形貌,结合极化曲线、电化学阻抗谱(EIS)和XRD分析污损生物附着对TC4钛合金腐蚀的影响,探索TC4钛合金在实海中的生物腐蚀机理。结果TC4钛合金具有良好的生物兼容性,大型污损生物附着以藤壶为主,数量多达4.5 pcs/cm^(2),覆盖面积占比呈“∫”型变化。试样表面无藤壶附着位置或藤壶与藤壶空隙之间无明显蚀坑,而藤壶附着位置出现蚀坑,随着时间延长形成溃疡坑。污损生物演替改变溶解氧向钛合金表面传输的效率,同时造成钛合金表面介质性质不均匀化,影响钝化膜的形成与再生,腐蚀电位、腐蚀电流及容抗弧半径波动变化。藤壶等污损生物不均匀附着形成“封闭滞留层”,导致出现富氧区和贫氧区,构成氧浓差电池,富氧区发生还原反应,贫氧区发生氧化反应,从而促进腐蚀。TC4钛合金表面形成含有TiO_(2)和Al_(2)O_(3)的钝化膜,而CaCO_(3)主要来源于钙质外壳污损生物。结论该海域污损生物附着以藤壶为优势物种,不同生长阶段的藤壶腐蚀机制不同,结构完整的活体藤壶钙质外壳和致密藤壶胶能够有效隔离外界腐蚀介质而抑制腐蚀,死亡藤壶则因壳体结构不完整与有机体被分解而促进腐蚀。污损生物附着使TC4钛合金表面发生复杂物化、生化和电化过程,导致试样在海洋环境中发生局部腐蚀,腐蚀速度非线性波动变化。

外文摘要：Titanium and its alloy are widely used in marine engineering equipment,and the marine environment is an extremely complicated natural environment.The complex marine environment has caused many severe tests of titanium alloy materials.Among them,biological attachment corrosion is one of the difficult problems that need to be solved.Therefore,this article has selected TC4 titanium alloys for research on biological adhesion and corrosion behavior,so as to provide a scientific basis for pollution-loss biological prevention and material corrosion protection.The polished TC4 titanium alloy samples were encapsulated with threaded joints and epoxy resin,and then put into the real sea of Tiaoshun Island in Zhanjiang,Guangdong.The research team observed the attachment and growth behavior of fouling organisms in different test cycles by soaking and hanging samples.The corrosion morphology of TC4 titanium alloy in different test periods was observed by ultra-depth-of-field microscope,and the influence of fouling organism attachment on the corrosion behavior of TC4 titanium alloy was analyzed by polarization curve and electrochemical impedance spectroscopy(EIS).The composition of corrosion products was analyzed by XRD,and the mechanism of biological adhesion corrosion of TC4 titanium alloy was explored.Results showed that TC4 titanium alloy had good biocompatibility in marine environments.Among them,macrofouling organism gave priority to barnacles,and the number of which was as high as 4.5 pcs/cm^(2).The proportion of barnacles to sample area changed in a"∫"shape.There was no obvious corrosion pit where was no barnacle attachment position or the gap between barnacles and barnacles on the surface of sample,but the barnacle attachment position had corrosion pit,which formed ulcer pit with time.The succession of fouling organism changed the efficiency of dissolved oxygen transfer to the surface of titanium alloy,and at the same time caused the inhomogeneity of the surface medium properties of titanium alloy,thus affecting the formation and regeneration of passive films.The electrochemical impedance and polarization results showed that the corrosion potential,corrosion current and capacitive reactance arc radius fluctuated.Fouling organisms such as barnacles were unevenly attached to form a"closed retention layer",which lead to oxygen-rich areas and oxygen-poor areas,forming an oxygen concentration difference battery.The reduction reaction occurred in the oxygen-rich region and the oxidation reaction occurred in the oxygen-poor region,thus promoting corrosion.A passive film containing TiO_(2) and Al_(2)O_(3) was formed on the surface of TC4 titanium Al_(2)O_(3),and CaCO_(3) mainly came from calcareous shell fouling organisms.In conclusion,barnacles are the dominant species for marcofouling organisms in this sea area.The corrosion mechanism of barnacles in different growth stages is different.The calcareous shell and dense barnacle glue of living barnacles with complete structure can effectively isolate the external corrosion medium to inhibit corrosion,while the dead barnacles promote corrosion because of the incomplete shell structure and the decomposition of organisms.The adhesion of fouling organisms makes the surface of TC4 titanium alloy undergo complex physicochemical,biochemical and electrochemical processes,which leads to local corrosion of the sample in marine environment,and the corrosion rate is nonlinear.