Physicochemical Study on Preparation of Oxidation-Resistant Films on High Temperature Materials and Their Oxidation Rate.

高温材料抗氧化膜的制备及其氧化速率的物理化学研究。

• 批准号: 63430013
• 负责人: NAGATA Kazuhiro
• 金额: $ 0.96万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (A)
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-63430013/
• 关键词: High Temperature Materials; Oxidation Resistance; Thin Film; SiO_2; Diffusion; Thermal Conductivity; Aluminide Coating; Molibudenum; 拡散係数; Mo_3Al_8; コ-ティング; グラファイト; 高温耐酸化性; コーティング膜; Al_4C_3; Al_2O_3; 熱伝導率; WO_3

Improvement of energy efficiency requires materials for high temperature use in oxidizing atmospheres. The coating of oxidation-resistant films on materials is one of the most favorable ways without the degradation of their mechanical properties. Silica and alumina are the potential materials for oxidation-resistant films at temperatures higher than 1000 C in oxidizing conditions. This research dealt with the physical chemistry involving in the preparation or formation of silica and alumina on the surface of high temperature materials, and the protective property against oxidation.(1) Physicochemical Study on Silica Films on Silicon (a)Mechanism of thermal oxidation of silicon Three kind of silica films were formed on silicon substrates by thermal oxidation, chemical vapor deposition and spin-on glass techniques. These samples were oxidized at elevated temperatures to evaluate the diffusivity of oxygen in the films. The diffusivity varied among the films because of the difference in th … More e microstructure. Oxygen pressure dependence of the oxidation rate indicated that the solubility of oxygen in the silica film was proportional to the oxygen pressure and that the diffusivity was independent of the pressure. (b)Development of a new technique for measurement of thermal conductivity of thin films A new technique named "Spot-Pulse Method" was developed, in which technique a pulsed laser beam was focused on the film and the change in surface temperature was measured. This technique proved to be applied the films with thickness more than 25mum.(2) Aluminide Coatings on Molybdenum for High Temperature Use (a)Pack-cementation coating of aluminum on molybdenum Aluminum was coated on molybdenum by pack-cementation. A thick film of Mo_3O_8 was formed and thin film of Mo_3Al existed between Mo_3O_8 and Mo. The coating layer contained many cracks which formed during cooling. The cracks were developed perpendicularly to the surface, and some of them reached the Mo substrate. The oxidation resistance of the coated Mo was poor because of the crack reaching the substrate although Mo_3O_8 itself exhibited the high resistance to oxidation forming a continuous Al_2O_3 fayer. (b)Two-stage coating of Si and Al Two-stage coating of Si and Al was developed, in which a small amount of Si was coated prior to the aluminide coating. Mirostructure of the two-stage coating was basically same as that of the aluminide coating but the marked suppression of the formation of cracks. The absence of cracks reaching the Mo substrate provided the extremely strong resistance to high temperature oxidation. Less

提高能源效率需要能够在氧化气氛中高温使用的材料。在材料上涂覆抗氧化膜是最有利的方法之一，且不会降低材料的机械性能。二氧化硅和氧化铝是在氧化条件下在高于1000℃的温度下形成抗氧化膜的潜在材料。本研究涉及高温材料表面二氧化硅和氧化铝的制备或形成及其抗氧化性能的物理化学。(1)硅上二氧化硅薄膜的物理化学研究(a)硅的热氧化机理通过热氧化、化学气相沉积和旋涂玻璃技术在硅衬底上形成了三种二氧化硅薄膜。这些样品在高温下被氧化，以评估薄膜中氧的扩散率。由于微观结构的差异，薄膜之间的扩散率有所不同。氧化速率与氧压力的关系表明，氧在二氧化硅膜中的溶解度与氧压力成正比，而扩散率与压力无关。 (b)开发测量薄膜热导率的新技术 开发了一种名为“点脉冲法”的新技术，该技术将脉冲激光束聚焦在薄膜上并测量表面温度的变化。该技术已被证明适用于厚度大于25μm的薄膜。 (2)高温用钼表面铝化物涂层 (a)钼表面包埋铝涂层 采用包埋方法在钼表面涂覆铝。形成厚厚的Mo_3O_8薄膜，Mo_3O_8与Mo之间存在Mo_3Al薄膜。镀层中存在大量裂纹，这些裂纹是在冷却过程中形成的。裂纹垂直于表面发展，部分裂纹到达Mo基体。尽管Mo_3O_8本身表现出较高的抗氧化性，形成连续的Al_2O_3层，但由于裂纹到达基体，涂层Mo的抗氧化性能较差。 (b)Si和Al的两阶段镀层 开发了Si和Al的两阶段镀层，其中在铝化物镀层之前镀有少量的Si。两阶段涂层的显微组织与铝化物涂层基本相同，但裂纹的形成得到显着抑制。由于没有裂纹到达钼基体，因此具有极强的抗高温氧化能力。较少的

项目成果

須佐匡裕,篠原秀幸,永田和宏,後藤和弘: "非晶質シリカ薄膜中の酸素の拡散" 日本金属学会誌. 54. 193-200 (1990)

Masahiro Susa、Hideyuki Shinohara、Kazuhiro Nagata、Kazuhiro Goto：“无定形二氧化硅薄膜中的氧扩散”日本金属学会杂志 54. 193-200 (1990)。

Masahiro Susa, Hideyuki Shinohara, Kazuhiro Nagata, Kazuhiro S. Goto: "Influence of Bromine on Thermal Oxidation of Silicon Subsrtates" Journal of the Japan Institute of Metals, 53, pp.1054-1061, (1989).

Masahiro Susa、Hideyuki Shinohara、Kazuhiro Nagata、Kazuhiro S. Goto：“溴对硅基材热氧化的影响”日本金属学会杂志，53，第 1054-1061 页，（1989 年）。

張力〓,後藤和弘: "表示素子WO_<3ー6>薄膜の作成とLi^+の拡散係数の測定" 日本金属学会誌. 53. 906-913 (1989)

张力〓，Kazuhiro Goto：“显示元件WO_<3-6>的薄膜的制备和Li^+的扩散系数的测量”日本金属学会杂志53. 906-913（1989）。

張力偉,後藤和弘: "表示素子WO_<3-6>薄膜の作成とLi^+の拡散係数の測定" 日本金属学会誌. 53. 906-913 (1989)

田伟、后藤一宏：“显示元件用薄膜WO_<3-6>的制备及Li^+的扩散系数的测定”日本金属学会学报53. 906-913（1989）。

Masahiro Susa, Kazuhiro Nagata, Kazuhiro S. Goto: "Mechanism of Thermal Oxidation of Silicon Substrates" Journal of the Japan Institute of Metals, 54, pp.33-40, (1990).

Masahiro Susa、Kazuhiro Nagata、Kazuhiro S. Goto：“硅基板热氧化的机理”日本金属学会杂志，54，第33-40页，（1990）。