过渡金属氧化物掺杂Ni-Cr基红外陶瓷涂层的制备及性能研究
发布时间：2018-11-20 05:41
【摘要】：高温红外辐射材料区别于日常生活中经常见到的常温红外辐射材料,后者辐射波段集中在远红外区域,主要用于织物和食品干燥等。而高温红外辐射材料在高温条件下长期服役,要求材料本身在近红外和中远红外波段具有较高的辐射率,并能满足一定的使用性能。目前,关于红外辐射材料的研究热点主要集中在尖晶石结构这类物质上,本文也是主要针对这类结构材料研究制备高性能陶瓷涂层。本实验室以Cr2O3、NiO作为主要成分制备红外辐射材料,并陆续分别研究制备了非金属氧化物和稀土掺杂的复合材料。结合实验室以往的研究方向,本次实验将继续以Cr2O3、NiO作为所选材料讨论添加物对体系结构及红外辐射率的影响,并制备出性能更加完善的新型复合材料。实验主要分为三个部分,第一部分是探究造粉工艺,优化团聚粉末的流动性,第二部分是制备陶瓷涂层并初步探讨Co3O4、MnO2、TiO2单种材料对体系红外辐射率的影响,第三部分是实验方案设计及性能检测,通过对实验数据的分析,确定了涂层中各组成物对红外辐射率的影响。本文制备涂层主要工艺流程为:先将配好的粉末制备成料浆,经过砂磨工艺减小原始颗粒尺寸,然后将最终料浆送入雾化盘雾化,在干燥塔内高温作用下得到复合团聚粉末。之后将团聚粉末在不同温度段下处理,最后得到喷涂粉末。采用等离子喷涂工艺,通过送粉器将最终得到的复合团聚粉末沉积在基片表面,获得满足使用要求的高温红外辐射涂层。利用马尔文粒度分析仪测试料浆粒度范围分布,采用FL4-1霍尔流速计测量团聚粉末的流动性及松装密度,综合分析得到最优的砂磨时间范围在45min左右。对喷雾干燥后的粉末样品进行SEM电镜扫描发现,喷涂前的焙烧工艺对粉末的流动性产生了一定的影响,粉末颗粒虽同样呈现球形,但表面有许多凹凸不平的区域出现,另外,采用等离子淬火工艺制备的粉末球形度完好,颗粒更加密实,表面也更加光滑,流动性最佳。采用TG-DSC测试方法,确定了焙烧粉末的两个重要温度点,450℃为本次实验所采取的第一温度点,主要用于粘接剂的挥发,1400℃为第二温度点,此温度下保温得到实验所需的尖晶石结构。对涂层进行XRD分析发现:当原料为Cr2O3、NiO、Co3O4、MnO2、TiO2五种成分时,形成了多种反尖晶石及混合尖晶石结构,涂层的红外辐射率经质检中心测试,在800~1000℃范围内均高于0.91,最高可达到0.92。制备的涂层具有良好的热稳定性和较好的结合强度。
[Abstract]:The high temperature infrared radiation material is different from the normal temperature infrared radiation material which is often seen in daily life. The latter radiation band is concentrated in the far infrared region and is mainly used in the drying of fabric and food. However, the high temperature infrared radiation materials have long service under the high temperature conditions, which requires that the materials themselves have a higher emissivity in the near and far infrared bands and can meet certain performance. At present, the research focus of infrared radiation materials is mainly on spinel structure, and the preparation of high performance ceramic coatings is also focused on this kind of structural materials. Infrared radiation materials were prepared by using Cr2O3,NiO as the main component in our laboratory, and non-metallic oxides and rare-earth doped composites were prepared respectively. Combined with the previous research direction of the laboratory, Cr2O3,NiO will continue to be used as the selected material to discuss the effects of additives on the system structure and infrared emissivity, and a new composite material with more perfect properties will be prepared. The experiment is mainly divided into three parts. The first part is to explore the powder making process and optimize the fluidity of agglomerated powder. The second part is to prepare ceramic coating and discuss the influence of Co3O4,MnO2,TiO2 single material on the infrared emissivity of the system. The third part is the design of the experimental scheme and the performance test. Through the analysis of the experimental data, the influence of the composition of the coating on the infrared emissivity is determined. In this paper, the main process of coating preparation is as follows: firstly, the slurry is prepared by mixing the powder, then the original particle size is reduced by the grinding process, and then the final slurry is sent into the atomizing disk to atomize, and the composite agglomerated powder is obtained under the action of high temperature in the drying tower. The agglomerated powder was then treated at different temperatures and the spray powder was obtained. The final composite agglomerated powder was deposited on the substrate surface by plasma spraying process and the high temperature infrared radiation coating was obtained by powder feeder. The particle size distribution of slurry was measured by Ma Erwen particle size analyzer and the fluidity and loose density of agglomerated powder were measured by FL4-1 Hall velocity meter. The optimum grinding time range was found to be about 45min by comprehensive analysis. SEM scanning electron microscopy showed that the roasting process before spraying had a certain effect on the fluidity of the powder. Although the powder particles were also spherical, there were many uneven areas on the surface. The powder prepared by plasma quenching has the advantages of perfect sphericity, more dense particles, smoother surface and the best fluidity. Two important temperature points of calcined powder were determined by TG-DSC method. The first temperature point was 450 鈩，
本文编号：2343940
[Abstract]:The high temperature infrared radiation material is different from the normal temperature infrared radiation material which is often seen in daily life. The latter radiation band is concentrated in the far infrared region and is mainly used in the drying of fabric and food. However, the high temperature infrared radiation materials have long service under the high temperature conditions, which requires that the materials themselves have a higher emissivity in the near and far infrared bands and can meet certain performance. At present, the research focus of infrared radiation materials is mainly on spinel structure, and the preparation of high performance ceramic coatings is also focused on this kind of structural materials. Infrared radiation materials were prepared by using Cr2O3,NiO as the main component in our laboratory, and non-metallic oxides and rare-earth doped composites were prepared respectively. Combined with the previous research direction of the laboratory, Cr2O3,NiO will continue to be used as the selected material to discuss the effects of additives on the system structure and infrared emissivity, and a new composite material with more perfect properties will be prepared. The experiment is mainly divided into three parts. The first part is to explore the powder making process and optimize the fluidity of agglomerated powder. The second part is to prepare ceramic coating and discuss the influence of Co3O4,MnO2,TiO2 single material on the infrared emissivity of the system. The third part is the design of the experimental scheme and the performance test. Through the analysis of the experimental data, the influence of the composition of the coating on the infrared emissivity is determined. In this paper, the main process of coating preparation is as follows: firstly, the slurry is prepared by mixing the powder, then the original particle size is reduced by the grinding process, and then the final slurry is sent into the atomizing disk to atomize, and the composite agglomerated powder is obtained under the action of high temperature in the drying tower. The agglomerated powder was then treated at different temperatures and the spray powder was obtained. The final composite agglomerated powder was deposited on the substrate surface by plasma spraying process and the high temperature infrared radiation coating was obtained by powder feeder. The particle size distribution of slurry was measured by Ma Erwen particle size analyzer and the fluidity and loose density of agglomerated powder were measured by FL4-1 Hall velocity meter. The optimum grinding time range was found to be about 45min by comprehensive analysis. SEM scanning electron microscopy showed that the roasting process before spraying had a certain effect on the fluidity of the powder. Although the powder particles were also spherical, there were many uneven areas on the surface. The powder prepared by plasma quenching has the advantages of perfect sphericity, more dense particles, smoother surface and the best fluidity. Two important temperature points of calcined powder were determined by TG-DSC method. The first temperature point was 450 鈩，
本文编号：2343940
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