等离子喷涂-物理气相沉积的气相沉积机理

发布时间：2018-01-15 20:19

本文关键词：等离子喷涂-物理气相沉积的气相沉积机理　出处：《无机材料学报》2017年12期 　论文类型：期刊论文

【摘要】：以等离子喷涂-物理气相沉积(PS-PVD)喷涂团聚的Zr O_2-7wt%Y_2O_3(7YSZ)粉末在五个喷距下制备了热障涂层。通过场发射-扫描电镜(FE-SEM)和X射线衍射(XRD)分析了五个涂层样品的微观结构和相成分差异。另外,通过发射光谱(OES)诊断研究了射流中7YSZ粉末气相浓度随喷距的变化。最后,阐述了3种不同的气相沉积涂层生长机制,说明了射流中粉末的状态和气相浓度对涂层结构的影响。研究表明:(1)350 mm和1800 mm喷距下形成的均是致密结构涂层,而650~1250 mm喷距下形成的是典型的PS-PVD柱状结构涂层。(2)350 mm喷距下制备的涂层由四方相(t’)和单斜相(m)氧化锆构成;当喷距大于650 mm时,涂层以四方相(t’)氧化锆为主。(3)350 mm喷距下涂层是由高浓度气相过饱和自发形核形成的新核和液/固粒子共同作用形成的;喷距650~1250 mm下,涂层生长以气相沉积于基体进行非自发形核为主,气相在射流中的自发形核为辅;喷距1800 mm下涂层由气相过冷凝固的粒子堆积而成。
[Abstract]:Plasma spray-physical vapor deposition (PS-PVD) spray agglomerated Zr O _ s _ 2-7wtand Ys _ 2 _ 2O _ 3 / T _ 7YSZ). The thermal barrier coatings were prepared under five spray distances. The microstructure and phase composition of the five coatings were analyzed by field emission-scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). The variation of gas phase concentration of 7YSZ powder with spray distance was studied by means of emission spectrum (OES) diagnostics. Finally, three different growth mechanisms of vapor deposition coatings were described. The effect of powder state and gas concentration on the structure of the coating is explained. The results show that the coating with dense structure is formed under the spray distance of 350mm and 1800mm. The typical PS-PVD columnar structure coating was formed at 650,1250mm jet distance. The coating was made by tetragonal phase and monoclinic phase. Zirconia composition; When the spray distance is greater than 650 mm. The coating is mainly tetragonal zirconia. The coating is formed by the interaction of new nucleation and liquid / solid particles with high concentration gas phase supersaturation spontaneous nucleation under the spray distance of 350mm. When the spray distance is 650 ~ 1250mm, the coating growth is mainly non-spontaneous nucleation by vapor deposition on the substrate, supplemented by the spontaneous nucleation of the gas phase in the jet. Spray distance of 1800 mm coating from gas-phase supercooled solidified particles stacked.
【作者单位】：广东工业大学材料与能源学院;广东省新材料研究所现代材料表面工程技术国家工程实验室广东省现代表面工程技术重点实验室;中南大学材料科学与工程学院;
【基金】：广东省自然科学基金团队项目(2016A030312015) 广东省广州市科学技术合作项目(2013B050800027,201508030001,2011C007) 广东省科学院项目(2017GDASCX-0843,2016GDASPT-0206,2016GDASPT-0317)~~
【分类号】：TG174.4
【正文快照】： 等离子喷涂-物理气相沉积(Plasma Spray-PhysicalVapor Deposition,PS-PVD)是20世纪末基于低压等离子喷涂(Low Prossure Plasma Spray,LPPS)发展出来的新一代等离子喷涂技术[1-4]。相比于传统的LPPS,PS-PVD具有更低的工作压力、更高的喷涂功率和更大的工作气体流量,从而可以实

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