| The rapid development of modern science and technology, the development of high temperature and high strength demands. In rockets, supersonic plane, cosmic voyage, metallurgy, electronic technology and modern new energy technology, composite materials in the field not only has high temperature resistant performance, but also has respectively resistance, resistance to impact, oxidation resistance and electrical properties. High-temperature composite materials because of its good high tempe-rature sex widely applicated in recent years, therefore become mechanics and material science research hotspot. Based on the existing experimental observation and theory on the basis of the research of the composite was studied under high temperature conditions of mechanical properties and its relevant rules, for composite materials in the structural design, strength and service life provides certain aspects of the theory basis.This paper mainly studies content as follows:1. The visco-elastic mechanism of particles reinforced composites has been investigated through revised Eshelby equivalent inclusion theory. A visco-elastic model is applied. Furthermore, by introducing Heaviside step function and Laplace transform, the creep constitutional equation related to strain rate effect is achieved. Finally, by equivalent inclusion theory, introducing secant modulus, the material moduli with time and volume fraction concerning Glass/ED6 particles reinforced materials have been given. The results show that the visco-elastic property of composite material is mainly determined by the visco-elastic behavior of the matrix, which meet experiment results well. It can be concluded from the results that there exits close relationship between the inclusion shape, volume fraction and loading path.2. Based on Eshelby equivalent incluision theory, with the three-parameter visco-elastic constitutive model, the mechanical response of Glass/ED6 short fiber reinforced composites has been invesgigated in this paper. Further, temperature effects of dynamic shear modulus and the thermal expansion coefficent of C/ED6 have been predicted. The results showed that the shear modulus has a close relationship with volume fraction and loading frequency and the thermal expansion coeficient is closely connected with temperature. ByμR·ω,μl·ω, μR·f,μl·f andα-ΔT curves, it can be found that the dynamic shear molulus is mainly determined by its real part when the loading frequency is high and when the volume fraction of fiber is high, the change of dynamic shear modulus is mainly determined by its imaginary part, which can simplify the computational process of material mechanical property.For C/ED6, with the increasing of temperature difference, the thermal expansion coefficent decreases. The present paper may provide theoretical backgrounds for material design and practical engineering application.3. The high temperature oxidation transformation behavior of ZrB2-SiC ceramics has been investigated. Combined with Arrhenius equation and meso-mechanical theory, the reinforcement phase, stomatal quest item and the substrate temperature change patterns have been given. According to Eshelby equivalent inclusion theory, the high temperature mechanical properties of the composites has been predicted, including elastic modulus with temperature and porosity changes, which will provide a theoretical background for the engineering application of high-temperature ceramics.4. In the existing domestic temperature composite material thermodynamics study basis, based on the analysis of the characteristic parameters of the microstructure of materials, heat/force coupling conditions of composite thermal and mechanical coupling analysis model. Then from the heat conduction and thermodynamics theory, the heat load on the composite material mechanics performance phenolic resin matrix is simulated, and a series of beneficial conclusion.
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