【摘要】 采用等离子喷涂法在涂覆SiC内涂层的炭/炭复合材料表面制备了Cr-Al-Si外涂层。采用XRD和SEM分析了涂层的物相组成及微观结构,并测试了复合涂层炭/炭复合材料试样在1500℃静态空气中的抗氧化性能。结果表明:合金外涂层主要由Al3.21Si0.47、Cr3Si及Al2O3组成,厚度约为120μm,无穿透性裂纹;多孔结构单一β-SiC内涂层的防氧化能力较差,氧化10 h后涂层试样的氧化失重就接近10%,外加Cr-Al-Si涂层后,涂层试样的氧化性能显著提高,氧化61 h后试样的失重仅为5.3%。更多还原

【Abstract】 Cr-Al-Si coating was prepared on the surface of SiC coated C/C composites by the plasma spraying method.The phase composition and microstructure of Cr-Al-Si coating were studied by XRD and SEM.The isothermal oxidation test at 1500℃ was carried out in air.The XRD results show that the outer Cr-Al-Si alloy coating consists of Al3.21Si0.47,Cr3Si and Al2O3.The thickness of the coating was about 120μm,and no penetrable crack was observed in the cross-sectional SEM morphologies of the coating.The oxidation resistance of the single porous β-SiC coating is poor,which can only protect C/C composites from oxidation for 10 h with a mass loss of 10%.After adding the Cr-Al-Si alloy outer coating,the double-layer Cr-Al-Si and SiC show a better oxidation protective ability and 5.3% mass loss of the coated sample after oxidation for 61h.更多还原