Preparation And Property Study Of Zirconia Ceramic Spring For High-temperature Elastic Element

Springs as one of the most commonly used mechanical foundation elements arewidely used in various mechanical devices.Metal is the most common springmaterial.But with the development of technology,the requirements of usingtemperature and conditions become more harsh.Metallic material is difficult to meetthe require. While ceramic spring appeared and precisely meet the requirements ofthese extreme conditions.Compared to common metal spring,ceramic spring has goodhigh temperature resistance.Compared to other non-metallic springs such as rubbersprings,ceramic spring has advantages of Wear-resistance and not heat.Zirconia as one of high toughness materials, widely used in oil exploration,engineproduction and other aspects of the life.When the temperature rises,the volumeexpansion of the material prevents the crack to expand in order to achievetoughening results.The body prepared by gelcasting has high density,high strength andlow shrinkage,often used in the production of complex shape products.The experiment primarily designed a ceramic spiral spring which used zirconia asthe raw material,by the way of gelcasting,can be applied to the high-temperatureenvironment of800°C above.The ceramic spring has a certain compressionresilience,which can be used in the sealing member of aerospace vehicles.In addition,according to different parameters of the mould we can produce ceramic spiral springof different parameters, in order to adjust parameters such aselastic modulus of thespring, to meet the requirements of different environmental conditions.In this study,the preliminary work is the exploration and improvements of the molding process oftthe high-temperature component,and the study of the design and preparation of theceramic spring.The latter work is a preliminary test and discussion about theproperties of the sample at room temperature,especially the elastic properties. Themain conclusions are:At1500°C, the crystal transformation completed,almost all exists in the form oftetragonal solid solution.In the1500°C sample fracture scanned picture,spiral-shapeddepression can be observed.It can be inferred that it is spiral-shaped fracture causedby tough fracture of the material,similar to plastic dimple when metal fractureoccurs.Analyzing1500°C is the most suitable sintering temperature.At room temperature, the elastic behavior of the ceramic spring is similar to metalspring.Hooke’s Law F=-kx is also applicable to ceramic springs.The compression rebound curve area is small, less energy is absorbed by deformation. Sinteringtemperature has little effect on the rebound performance of zirconia ceramicspring,but for their performance related to the strength of the material, has someinfluence,for example,the maximum load. The low pitch sample sintered at1500°Conly has the spring constant of14.95N/mm, the axial strain of12.5%.That is to say,thesample of this parameters can be used in the environment where the deformationbelow10%and the maximum load less than30N.The effect of different parameters on the spring constant:With the pitchincreases,the spring constant increases.With the middle diameter increases,the springconstant reduces.With the wire diameter increases, the spring constant increases.Theceramic spring has good performance on cyclic loading,and the fatigue characteristicscan not be observed.