烧结温度对防氧化涂层性能影响研究

研制了一种以磷酸盐涂层和陶瓷涂层相结合的新型复合防氧化涂层，针对不同的烧结温度研究了这种复合涂层的防氧化性能。结果表明：在700℃静态氧化30h后，800℃烧结的复合涂层试样的氧化失重率最小，为0．99％，经过900℃、3min←→室温、2min30次和1100℃、3min←→室温、2min10次连续热震后，其氧化失重率仅为0．31％，氧化速率为1．34×10^-7g·cm^-2·s^-1。SEM观察结果显示不同烧结温度制备的涂层表面微观形貌明显不同，800℃烧结的涂层表面完整致密，氧化后涂层仍然保持完好，没有脱落，说明该涂层与炭基体的结合性能以及热稳定性能良好，适合作为飞机炭刹车副的防氧化涂料。

PROPERTIES OF ANTI - OXIDATION COATINGS FOR CARBON/CARBON COMPOSITES PRAPERATED AT DIFFERENT SINTERING TEMPERATURE

A multiple anti-oxidation coatings used for carbon/carbon composites were prepared, which consists of phosphatic coating and ceramic coating. The antioxidation properties of the coatings preparated at different sintering temperatures were studied by weight loss and thermal cyclic performances. Results show that the minimal weight loss was only 0.99% oxidated at 700℃ for 30 h in air,which sintered at 800℃ .The weight loss percent and oxidized rate of the sample after thermal shock were 0.31% and 1.34×10^-7g·cm^-2·s^-1, respectively, circulated in air from 900℃ for 3 min to room temperature for 2 min for 30 times shock and from 1 100℃ for 3 rain to room temperature for 2 rain for 10 times shock. Microstructures of coatings show that different microstructures may be obtained by different sintering temperatures. The coatings after oxidation sintering at 800℃ present compact, integrated and non-spalling stucture. This indicates that the multiple anti- oxidation coatings can provide excellent oxidation resistance, thermal shock resistance and be applied to the protection of carbon/carbon composites.