Synthesis of RF Plasma-sprayed Coatings Based on the Controls of Droplet Flattening, Solidification and Reaction Step

基于熔滴压平、凝固和反应步骤控制的射频等离子喷涂涂层的合成

• 批准号: 09450280
• 负责人: TSUNEKAWA Yoshiki
• 金额: $ 8.7万
• 依托单位: Toyota Technological Institute
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09450280/
• 关键词: Plasma Spraying; In Situ Composite; Nitrogen-mixed Plasma; Methane-mixed Plasma; Splat morphology; Nitride; Carbide; Structure Control; 高周波プラズマ溶射; スプラット; 構造制御; 粒子直径; Ti_2AlN; 金属間化合物; 超音波振動; 反応性溶射; 窒素プラズマ; 扁平化; 凝固; 窒化反応; 生成複合化

This research has been performed to understand the fundamental phenomenon in the synthesis of metal and intermetallic matrix composite coatings by reactive RF plasma spraying with premixed elemental powder, which is based on the droplet flattening, solidification and reaction with gases.Typical splat morphology of impinged titanium droplets on a substrate is a disk-type with an outer peripheral fringe. If the supplied titanium powder size becomes finer or the nitrogen partial pressure, splats containing prominent asperities (TiN) with a smaller flattening ratio appear along with the plain disk-type. Aluminum splats are also classified into two categories : a disk-type with an irregular outer periphery and a semi-nodular-type. Oxygen exists on the splat surfaces, on which there are nitrogen concentrated areas corresponding to AIN. Consequently, the nitride formation proceeds on titanium and aluminum droplets during the flight as well as on the substrate. If the substrate temperature in … More higher than 873 K just before spraying with premixed titanium and aluminum powder, the formation of TiAl and TiィイD22ィエD2SIN proceeds on the substrate.In situ composite coatings containing titanium carbide (TiC) precipitates were synthesized by reactive RF plasma spraying with elemental titanium powder, in which the effect of methane concentration premixed into the plasma gas on the TiC formation was examined through the process. The absorption of decomposed carbon into molten titanium droplets occurs during their flight in the plasma flame, so that fine TiC precipitates which increase in volume with mixed methane are recognized in the sprayed titanium particles. The flattering ratio of splats impinged on a substrate decreases with increasing premixed methane. The amount of TiC precipitates in titanium matrix coatings is approximately five times higher than that in sprayed particles during their flight regardless of premixed methane. Hence, the TiC formation is dominated at the splat depositing step, because the time exposed by the methane mixed plasma flame is much longer than the flight time of droplets. The maximum volume fraction of TiC precipitates is approximately 30 vol% in the coatings. Less

本文研究了反应性射频等离子喷涂预混合元素粉末制备金属和金属间基复合涂层的基本现象，即液滴的压平、凝固和与气体的反应。钛液滴在衬底上撞击后的典型飞溅形态是具有外围条纹的圆盘型。当供给的钛粉粒度变细或氮气分压增大时，会出现扁化比较小的含突出凸起（TiN）的片状片状。铝板也分为两类：圆盘型与不规则的外周和半结节型。氧存在于板条表面，板条表面有氮的集中区域，对应于AIN。因此，在飞行过程中，钛和铝液滴以及衬底上的氮化物形成继续进行。预混合钛铝粉末喷涂前，基底温度大于873 K时，基底上进行TiAl和Ti的生成。采用反应射频等离子喷涂法合成了含碳化钛（TiC）沉积的原位复合涂层，并考察了等离子气体中预混的甲烷浓度对TiC形成的影响。熔融钛液滴在等离子体火焰中飞行时，分解后的碳被吸收到熔钛液滴中，从而在喷射的钛颗粒中识别出体积随混合甲烷增加的细小TiC析出物。随着预混甲烷的增加，撞击基材的碎片的奉承比减小。在飞行过程中，钛基涂层中TiC析出物的数量大约是喷射颗粒中TiC析出物的5倍。因此，由于甲烷混合等离子体火焰暴露的时间远长于液滴的飞行时间，TiC的形成主要发生在溅射沉积阶段。TiC析出物在涂层中的最大体积分数约为30 vol%。少

项目成果

Y.Tsunekawa, M.Hiromura, M.Okumiya: "Nutriding of Metal Droplets in Synthesis of Intermetallic Matrix Composite Coatings by Reactive RF Plasma Spraying"Proceedings of 15th International Thermal Spray Conference, C.Coddet ed., ASM International. 1143-1148

Y.Tsunekawa、M.Hiromura、M.Okumiya：“通过反应性射频等离子喷涂合成金属间基质复合涂层中的金属液滴的氮化”第 15 届国际热喷涂会议论文集，C.Coddet 编辑，ASM International。

Y.Tsunekawa et al: "Nitride Formation in Synthesis of Titanium Aluminide Matrix Composite Coatings by Reactive RF Plasma Spaying"J. Thermal Spray Tech.. 9(in press). (2000)

Y.Tsunekawa 等：“通过反应射频等离子体喷涂合成铝化钛基复合涂层中氮化物的形成”J。

Y.Tsunekawa et al: "Reaction of Metal Droplets during Flight and on Substrate in Reactive Low Pressure DC Plasma Spraying" Proc.SMT11, ASM International. 234-245 (1998)

Y.Tsunekawa 等人：“反应性低压直流等离子喷涂中飞行过程中金属液滴和在基材上的反应”Proc.SMT11，ASM International。

Y.Tsunekawa et al: "Nitriding of Metal Droplets in Synthesis of Intermetallic Matrix Composite Coatings by Reactive RF Plasma Spraying"Proc. 15th ITSC, ASM International. 1143-1148 (1998)

Y.Tsunekawa 等人：“通过反应射频等离子喷涂合成金属间基质复合涂层中的金属液滴氮化”Proc。

K.Tanaka, Y.Tsunekawa, M.Okumiya: "Synthesis of Titanium Silicide Matrix Composites"Proc. 9th CIMEC-World Forum on New Materials Symposium. 397-406 (1999)

K.Tanaka，Y.Tsunekawa，M.Okumiya：“硅化钛基复合材料的合成”Proc。