CeO2添加剂对Cr2O3涂层组织和抗热震性的影响

本文在Cr     

料浆烧结法制备铌基Y2O3涂层的组织及抗热震性能

为推动核工业乏燃料回收再利用,满足熔炼核金属用坩埚的多轮次有效服役的要求,本文采用料浆烧结工艺在Nb-5W-2Mo-1Zr(Nb521)合金表面制备一系列双层复合Y₂O₃涂层,添加微量Si、Mo作增强剂,表面均为纯Y₂O₃涂层。借助有限元模拟、X射线衍射仪、扫描电镜、能谱仪等手段分析涂层的组织及抗热震性能。结果表明：Nb/Y₂O₃涂层呈典型的层状结构,由不规则的粉末颗粒相互堆叠而成,基体区、扩散区、过渡层、纯Y₂O₃层结构分明;有限元模拟计算及实验结果均证明双层梯度涂层可改变应力分布并有效减缓热冲击时材料内部应力的产生,其中,70%Y₂O₃+22%Nb+6%Si+2%Mo(7022)涂层的最大主应力为163.2 MPa,相较单层Y₂O₃涂层(313.4 MPa)下降47.93%。60次热循环后,7022-Y₂     

Al2O3 含量对 YSZ 热障涂层性能的影响

Al_2O_3等氧化物对YSZ热障涂层的高温使用性能有一定的影响。本文用HVOF喷涂Ni Co Cr Al Y合金粘结层,APS喷涂YSZ陶瓷面层,制备了Al_2O_3含量为0.01~0.64wt%的YSZ涂层。比较了不同Al_2O_3含量的YSZ涂层在1100℃下的热震性能和抗烧结性能,并探讨Al_2O_3对涂层的影响机理。结果表明相较于高纯YSZ涂层,随着涂层中Al_2O_3含量升高,涂层的抗热震性能降低,且Al_2O_3促进YSZ涂层的烧结。Al_2O_3含量在小于0.01wt%-0.12wt%区间内时,对涂层抗热震和抗烧结性能有显著影响,含量继续增加至0.64%时,对性能影响减缓。显微组织观察与EDS检测结果表明涂层中Al_2O_3并未在熔融颗粒界面处偏聚,但在颗粒内部有局部偏析。由此推测,含Al_2O_3的YSZ涂层热震失效的原因可能是Al_2O_3在YSZ颗粒内部偏析,并影响涂层的烧结性能,导致裂纹容易萌生和扩展。     

CeO_2添加剂对Cr_2O_3涂层组织和抗热震性的影响

本文在 Cr2 O3陶瓷材料中添加不同含量的 Ce O2 ,探讨了 Ce O2 对等离子喷涂 Cr2 O3涂层组织和抗热震性的影响。研究结果表明 ,加入 3.0 % Ce O2 可降低涂层中的孔隙率和空洞尺寸 ,减少涂层内应力在孔隙边缘的应力集中 ,从而提高 Cr2 O3涂层的抗热震性。陶瓷涂层的热震失效是由于涂层在循环加热和冷却过程中 ,涂层内产生循环热应力 ,导致涂层发生热疲劳失效     

掺杂ZrO2对Laβ-Al2O3固体电解质的性能影响

研究了掺杂不同量的ZrO₂对Laβ-Al₂O₃固体电解质的电导和抗热震性能的影响。结果表明ZrO₂的加入导致电导率下降,抗热震性能提高。为此,以加入质量分数10%ZrO₂为宜。     

CeO2添加量对45钢表面激光熔覆Ni-WC涂层的组织和性能影响

利用二氧化碳激光器在45钢基体表面上熔覆Ni-WC-CeO₂的复合涂层,使用扫描电镜、EDS、显微硬度计、洛氏硬度计,研究CeO₂添加量对Ni-WC-CeO₂复合涂层宏观形貌、显微组织、元素分布、表面硬度及纵截面显微硬度的影响,以找到最佳的CeO₂添加量。CeO₂的添加有助于改善涂层宏观形貌、基体和涂层的扩散及浸润性,细化微观组织及WC形貌,提高涂层表面硬度和纵截面显微硬度。CeO₂添加量存在一个最佳值：当CeO₂添加量为0.3%时,Ni-WC-CeO₂复合涂层表面无渣、无裂纹、较小润湿角,宏观形貌最好,从表面到与基体结合处涂层显微组织无枝晶,组织明显细化,Ni-Cr合金与WC间、涂层与基体间的元素发生明显互扩散,碳化钨形貌细化且分布较为均匀,涂层表面硬度最高,所有涂层纵截面显微硬度均呈现中间高两端低的“山形”分布;当CeO₂添加量为0.25%时,每组纵截面显微硬度几乎都高于其他CeO     

溶胶制备工艺对ZrO2-Y2O3涂层性能的影响

用无机金属盐水解及有机醇盐中间体合成两种不同的工艺路线制备了ZrO₂-Y₂O₃复合Sol(溶胶),对比了通过Dip-Coating的方法在GH220/MCrAlX基体上形成致密ZrO₂-Y₂O₃陶瓷涂层的能力,以及涂层在1000℃的静态抗氧化性能.结果表明,金属有机醇盐工艺制备的ZrO₂-Y₂O₃陶瓷涂层具有极其优越的高温静态抗氧化性能.无机金属盐水解所制备的ZrO₂-Y₂O₃涂层抗氧化能力明显低于金属有机醇盐工艺.可能的原因是残留在涂层内的微量酸根离子使氧化和腐蚀过程加剧.     

NiFe2O4基惰性阳极抗热震性的研究进展

综述了铝电解用NiFe2O4型惰性阳极材料抗热震性能的研究现状。简要的介绍了材料抗热震断裂的理论,评述了NiFe2O4基金属陶瓷抗热震性的有关研究情况,概述了NiFe2O4型惰性阳极今后的研究重点及发展方向。     

CeO2/Cr3C2对WC-Co-Ni基硬质合金电化学腐蚀行为的影响

为了探讨WC-Co-Ni基合金腐蚀性能提升路径,采用相同基础原材料,制备WC-6Co-6Ni、WC-6Co-6Ni-1.0Cr₃C₂、WC-6Co-6Ni-1.0CeO₂和WC-12Co-1.0CeO₂等4种合金。分别在NaOH(pH=13)、Na₂SO₄(pH=7)和H₂SO₄(pH=1)等3种腐蚀介质中对4种合金进行电化学阻抗谱和动电位极化曲线测试。结果表明,腐蚀介质对合金耐腐蚀性能及其腐蚀机理具有重大影响,合金添加剂Cr₃C₂和Ni能够提升WC-Co-Ni基硬质合金在Na₂SO₄中性介质中的耐腐蚀性能,而在WC-6Co-6Ni合金中添加1.0%Cr₃C₂会降低合金在NaOH介质中耐腐蚀性能;WC晶粒相对细小的WC-12Co-1.0CeO₂合金在NaOH介质...     

热喷涂玻璃-Cr2O3陶瓷涂层的性能

以SiO2-Al2O3系玻璃与Cr2O3陶瓷粉末为原料,采用高温烧结、球磨破碎工艺制备玻璃态物质包覆Cr2O3陶瓷颗粒的玻璃-Cr2O3陶瓷复合粉末,利用氧-乙炔火焰热喷涂技术在45号钢表面喷涂SiO2-Al2O3-Cr2O3玻璃陶瓷保护涂层。利用扫描电镜(SEM)对SiO2-Al2O3-Cr2O3玻璃陶瓷粉末与涂层的微观形貌进行表征。采用粘接拉伸法检测涂层与基体的界面结合强度,在介质溶液中进行腐蚀实验,研究玻璃与陶瓷粉末的配比对涂层微观结构与性能的影响。研究表明:当SiO2-Al2O3系玻璃的含量(质量分数)为40%时,涂层具有较好的综合性能,与基体的结合强度达30.4MPa,在10%CH3COOH溶液(体积分数)、8%NaOH溶液(质量分数)和3.5%NaCl溶液(质量分数)中腐蚀120 h的腐蚀速率分别为112.6、87.1和83.1 mg/(h.m2)。     

Methods of Increasing the Thermal Resistance of Articles Made from Ceramic with Two-Sided Protective Coating

The influence of the size and shape of the parts of containers made of laminar ceramic on the thermal resistance of containers is qualitatively estimated. The coefficient in the estimation formula for thermal resistance which expresses the influence of shape and size on the thermal resistance of manufactured articles is broken down into several factors. These factors depend on the properties, shape, and size of the ceramic base and coating and the boundary between them. A model that shows how to reduce the influence of the individual factors in the thermal resistance formula on the thermal resistance of the entire article is proposed. A method of reducing this influence by soldering articles from individual parts of simplified shape is developed. Comparative tests of vessels made of quartz ceramic with a protective coating of Nb₂O₅ and assembled according to the proposed method were conducted. Qualitative observations of acoustic emission in the cooling process demonstrated that based on the proposed model, a substantial increase in the thermal resistance of vessels can be achieved by manufacturing the vessels from laminar ceramic.__________Translated from Poroshkaya Metallurgiya, Nos. 3–4(442), pp. 49–54, March–April, 2005.     

稀土对SHS陶瓷涂层影响的研究

本文研究了稀土对两种组成的ＳＨＳ（Ｓｅｌｆ－ｐｒｏｐａｇａｔｉｎｇＨｉｇｈＴｅｍｐｅｒａｔｕｒｅＳｙｎｔｈｅｓｉｓ）陶瓷涂层的影响。试验得出稀土可改善正常配比陶瓷涂层的组织形态，减少涂层孔隙，提高金属—陶瓷涂层复合管的力学性能和抗热冲击性；相反，对含ＳｉＯ２组成的涂层组织形态和相应复合管力学性能产生不利影响     

Effects of Additive CeO_(2) on Thermal Shock Resistance of Plasma- Sprayed Cr_(2)O_(3) Coating

The influence of CeO2with different content on the thermal shock resistance of plasmasprayed Cr2O3 coating was investigated. The thermal shock failuremechanism of coating was alsostudied. It is found that the thermal shock failure mechanism ofcoating is thermal stress fatiguedestruction, and the destructiontakes place at interface of ceramicand bond coating. The experimental results show that the lifetime ofcoating fracture and failure increase considerably when 3% CeO2is added into the plas…     

Effect of Al2O3 on Structure and Wearability of Composite Coating

Asasurface strengtheningtechnology ,thether malsprayhasevolvedfromearlynormal protectivecoatingtocurrentfunctionalcoating .Thedevelopmentofcompositepowderisanimportantbreakthroughinthisfield .Particularly ,thenewlydevelopedmetal basedceramiccoatings ,such…     

Study on Mg PSZ Ceramics Doped with Y_2O_3 and CeO_2

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Fabrication and Mechanical Properties of Sm2O3 Doped CeO2 Reinforced Ti3AlC2 Nano Composite

The fabrication process of Sm2O3 doped CeO2 reinforced Ti3AlC2 nano composites including the nano particle dispersion process by a hetero-coagulation process was developed using in-situ synthesis and densification process of Ti3AlC2. The effects of Sm2O2 doped CeO2 nano particles on mechanical properties of Ti3AlC2 were investigated. It was found that the presence of 20SDC nano particles in Ti3AlC2 was very effective to improve the mechanical properties of Ti3AlC2 without spoiling the unique characteristics of Ti3AlC2temary carbide.     

含CeO2的紫味兰陶瓷颜料的研究

采用共沉淀法于低温下合成了含少量稀土氧化物CeO2的紫色陶瓷颜料,并采用颜色测定、SEM、XRD及能谱分析等手段对颜料的颜色、粒度及结晶构造等进行了表征。同时,将合成的颜料应用于陶瓷高温釉料中,表明该颜料可以应用于1320℃的高温。     

CeO2对激光熔敷合金层组织和腐蚀磨损性能的影响

用Ｘ射线衍射仪、ＳＥＭ、ＴＥＭ和电子控针研究了稀土氧化物ＣｅＯ２对Ｎｉ６０－ＷＣ激光熔敷层的相结构、显微组织以及腐蚀磨损性能的影响,试验结果表明Ｎｉ６０＋２０％ＷＣ＋０．５％ＣｅＯ２熔敷层的抗腐蚀磨损性能最好。     

Effect of Rare Earth on Thermal Shock Resistance of Steel 9Cr2Mo

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