LY12铝合金微弧氧化/树脂填料复合涂层的组织与防热性能

为提高LY12铝合金的隔热与抗火焰烧蚀性能,采用微弧氧化及涂覆复合工艺在其表面制备了底层微弧氧化/外层树脂填料复合涂层。用自制隔热装置及氧-乙炔烧蚀装置分别评价涂层的隔热与抗烧蚀性能。隔热测试表明试样暴露在450℃恒温6 min时,微弧氧化/莫来石空心微球树脂复合涂层隔热温度为245℃。微弧氧化/微球树脂复合涂层在2200℃氧-乙炔火焰下烧蚀持续25 s,质量烧蚀率为0.0425 g.s-1,线烧蚀率为0.0478 mm.s-1,复合涂层烧蚀区域背面均无变化,烧蚀条件下微弧氧化/微球树脂涂层隔热温度为1859℃,其隔热性能与450℃静态隔热测试结果一致。铝合金表面微弧氧化/树脂填料复合涂层表现出优异的隔热与抗烧蚀性能。

Microstructure and thermal protective performances of MAO/fillers reinforced resin matrix composite coating formed on LY12 alloy

In order to provide good protection of heat insulation and flame ablation,microarc oxidation (MAO)and MAO/fillers reinforced resin matrix composite coatings were prepared on LY12 aluminum alloy.The performances of heat insulation and flame ablation resistance were evaluated by the self-made heat insulation equipment and oxygen-acetylene ablation device.Exposure at 450 ℃ for 6 min,the heat insulation temperature for MAO/hollow mullite microsphere reinforced resin is 245 ℃.Exposure in oxygen-acetylene flame at 2200 ℃ for 25 s,mass loss rate and linear ablation rate is only 0.0425 g·s~(-1) and 0.0478 mm·s~(-1),respectively.The corresponding ablation back area finds no trace of ablation.The heat insulation temperature of MAO/ hollow mullite microsphere reinforced resin coating when exposing in the flame ablation is 1859 ℃.The result of heat insulation is consistent with that of the static heat insulation test at 450 ℃.In comparison,the MAO/fillers reinforced resin composite coating exhibits excellent ablation resistance and heat insulation performance.