Study On The Light And Thin Thermal-proof Composite Materials

When the aviation and space weapons are flying, the surface temperature of the weapon will increase sharply because of severe air friction, which will lead inner commanding electrocircuit out of operation, when it is severe, the system will be destroyed abruptly . The project aims at solving the weapon thermal-insulation problem in launching process, meeting the demands of commanding system thermal insulation in hanging or self-determination flight and developing a kind of light, thin thermal-insulation material.The inorganic fiber materials have been wildly used in many military and civil fields for their low density and low thermal conductivity, but now the unitary structure thermal-insulation fiber material can't meet the thermal-insulation demand here and the heat-barrier coating used wildly has the fatal disadvantage of splitting when temperature increases sharply, therefore a kind of multi-layer thermal-insulation composite was investigated based on the preparation method for high efficient thermal insulation materials at abroad.On the basis of determining the method of selecting inorganic fiber thermal-insulation materials, the microstructure of many kinds of thin thermal-insulation products were studied with SEM and their ignition loss was tested, then the optimum raw materials were selected. When all these products were arranged in some order, the composite materials with different microstructure could be obtained.On the basis of determining raw materials, two process such as sewing and adhesion were proceeded. The simulated mould was designed and installed. The states of adhensive between the composite layers and on the surface of fiber products were observed by SEM. The cohesiveness was tested by means of composite materials laniating-resistance test, practical usage effect test and environment adaptability test. The adhensive with good thermal insulation function was made by means of adding thermal-proofmaterial to the adhensive. The microstructure of light porous power was observed by SEM. The optimum thermal-resistance powder was selected as additive considering the powder microstructure and thermal conductivity.In order to test the thermal-insulation effect of the composite material, the simulated temperature test equipment was designed. In consideration of the thermal-insulation mechanism and the demand of water-proof for the material, the composite material structure was designed primarily. On this basis, the composite material structure was optimized according to the material thermal-insulation performance and the material that could be satisfactory to the service conditions was made in the end .The structure of the inorganic fiber material is loose, the capillary effect made the material of strong bibulous ability. For the water thermal conductivity is higher than that of the air, the thermal-insulation ability of the inorganic fiber material was declined as delaying deposit time. At the same time, the wetted material has influence on the electrocircuit function, so the water-proof treatment is quite necessary for it. The surface of the composite thermal-insulation material need hydrophobicity treatment,so two kinds of silicone are researched here, one can form a film on the surface of composite material. After being treatment, which can change the surface performance from hydrophi1icity to hydrophobicity, another one is vulcanized silicon rubber, which is suitable for sealing the side of composite material.