| With the construction of modern industry and the rapid development of national defense, the equipment have become increasingly demanding with high temperature performance. Compared with other methods of high temperature oxidation corrosion resistance, high temperature coating was widely used in steel chimneys, heat pipes, high temperature furnaces, oil installations and military equipment by a large area of good performance construction technology, low cost, effectiveness and other advantages. It can slow down thermal oxidation corrosion of steel and other metal equipment and ensure long-term using of equipment in the high temperature.This article researched a low melting point borosilicate glass as a filler of coating. The effect of sintering process and glass content on the coating properties was researched. A heat-resistant silicone resin is selected as a good coating of organic material by TGA and IR test. The glass filler, silicone resins, solvents and other additives was formulated into a high-temperature coating according to a certain percentage. The temperature resistance, flexibility, drying time and adhesion properties was tested.The main results obtained through the study were as follows: 1) Four kinds of silicone resins for TG and IR test analysis showed that the decomposition of methyl silicone resin, phenyl and other organic groups took place between 100℃~ 530℃by 180℃curing for 2h. The mass loss of silicon resin B is about 6.50%, less than the other three resins at this temperature range. Compared with the four kinds of resin in the heating process of weight loss and thermal weight loss between 100℃~ 530℃, silicon resin B is choosed as the resin-based material of coating. 2) By the prepared process of low melting borosilicate glass powder, alkali metal oxide Li2O had effect on lowing the transition temperature and softening temperature. Transition temperature Tg is decreased from 458℃to 430℃and softening temperature Td is decreased from 505℃to 473℃by adding 0 ~ 8mol% Li2O. Expansion coefficientαis increased from 8.8×10-6℃-1 to 10.0×10-6℃-1. Chemical stability of glass is improved but the transition temperature Tg and softening temperature Tf were no much improvement by adding 2-3mol% Al2O3. The performance of borosilicate glass is improved by adjusting the R2O (Li2O, Na2O, K2O) ratio. 22 # glass powder Td is 448℃and expansion coefficient is 11.89×10-6℃-1 that is obtained finally. Good infiltration of the substrate and mobility is showed by the sintering of glass powder and liquid performance test. The glass powder can be used in the coating. 3) The best heat-resistant and other properties coatings for formula is determined by the test: resin 35～40wt%, amino resin 7～9wt%, glass powder 30～40wt%, a black pigment 10～15wt%, coupling 2～3wt%, mica and talc 10wt%. The film adhesion is two level after the program grid test through insulated for1h at 700℃. Properties and heat resistance of the film were achieved the desired goals.In this paper, good heat resistance, high temperature coating adhesion coating is prepared by choosing resin and preparing low melting point borosilicate glass powder . This research will enrich the basic research of high-temperature coating, A high performance, low-cost preparation of technical route is provided for the high temperature (400℃~ 700℃) coating.
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