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This paper deeply studied the limitation of evaluating the thermal shock resistance of Al2O3-SiO2 refractory by measuring Strength Loss Rate (SLR). By means of supersonic, X-ray diffraction (XRD), the results were drawn as followed.1)After the thermal shock experiment for mullite based A-S refractory, which were composed by mullite and corundum, the supersonic velocity slowed down as it going through the sample while the cold crushing strength abnormally increased at initial state.2) The strength increased remarkably with the ascending of mullite fraction.3)It is inadequate to evaluate the thermal shock resistance of mullite based A-S refractory by strength loss rate.

The Al2O3-Cr2O3 slag as raw material was analyzed by scanning electron microscopy (SEM). The effects of different size distribution of MgO-Al2O3 spinel grain on physical properties of refractory bricks made from Al2O3-Cr2O3 slag was studied according to YB/T376.1-1995（water quenching）, GB/T 5072－1985, GB/T 2997-1982 criterion. The results show that the main crystal phase of the refractory bricks were chromium corundum, corundum. The refractory bricks containing 10 wt% of the maximum size of 3.0 mm of MgO-Al2O3 spinel grain can significantly improve the thermal shock resistance of this refractory bricks. At the meanwhile, This kind of refractory bricks can be absolutely satisfied with the requirements about cold crushing strength, bulk density and apparent porosity.

This paper mainly discuss the TiO2 on synthesizing the crystal structure of the cordierite, crystallinity, grain size, sintering properties. Use the software of X 'Pert plus to fit the XRD diagram, analyzing the properties of the crystallization, with the Scherrer formula to calculate the size of the cordierite in the specimen, discussing the TiO2 on synthesizing the crystal structure of the cordierite, the influence of microcosmic structure and sintering property can be carried out analysis with SEM. The results show that moderate introducing TiO2 in the process of the cordierite synthesis can easily make the crystal defects, but it can reduce the diffusion resistance of the particle, improve the particle diffusing speed and make the crystallinity of crystallization phase and grain size increase in sample. Due to the radius of the solute ion are greater than the radius of the solvents ion and to some degree the "inflation" function of the clearance of ions can also promotes the volume of the crystal cell. Introduction of excessive TiO2, the density of the sample and the sintering property is better, but the property of crystallization is declined.

A systematic study has been carried out to investigate matrix properties by introducing nmSiO2 fillers into an epoxy resin matrix. The study has revealed that with shock wave method, nanoparticle infusion brings about superior mechanical properties to the matrix than what is usually given by the other method. The nmSiO2 is dispersed in a high-energy liquid shock wave pressure processing. The resulting structural composites have been tested under tensile loads to evaluate mechanical properties. Shock wave mixing utilized high-energy, high voltage transient shock wave in the water medium to process the material lying in the focal area. Nanoparticles tend to reduce void content of the nanocomposites and thus translate into increased mechanical properties. Focused, the influence of the high-energy shock wave method on the mechanical properties of nanocomposite were systematic studied. Using different processing conditions, the experiments were done to find the best processing. Overall, shock wave method is shown as a promising methode for preparation of aerospace epoxy composites.