An efficient Al₂O₃-based nanocomposite coating was developed to fabricate the top thermally insulative layer of the thermal barrier coatings (TBCs). Here, Al₂O₃-based coatings were prepared by atmospheric plasma spraying and the scratch properties were investigated using progressive-load scratching. Scratch mechanism and the role of carbon nanotube (CNT), 3 and 8 mol% Y₂O₃ stabilized ZrO₂ (3YSZ and 8YSZ, respectively) during progressive load scratching were analysed. The investigations revealed that the Al₂O₃-based nanocomposite coatings were showed a high scratch coefficient (0.165–0.219) compared to that of monolithic Al₂O₃ (0.128). Also, the monolithic Al₂O₃ coating showed a decent scratch resistance (0.35 mm³N⁻¹ m⁻¹) compared to 3YSZ/8YSZ and CNT reinforced nanocomposite (0.49–69 mm³N⁻¹ m⁻¹). It was attributed to the synergistic effect of hardness, fracture toughness and the bonding of the reinforcement with the matrix Al₂O₃. The work of adhesion of lamella in the YSZ and CNT reinforced nanocomposite was measured as 1.16–2.75 × 10³ J, which is lower (up to 2.5 times) than the monolithic Al₂O₃ (2.91 × 10³ J). It is attributed to the poor bonding of CNTs with the lamella contains Al₂O₃ and YSZ. Further, the failure of the nanocomposite coatings, such as flaking and chipping were resisted by CNT. Nevertheless, CNT addition declines the scratch toughness of the nanocomposite coatings (1.05–2.04 MPa.m^0.5). It endorses no effective contribution of CNT in the scratch toughness of the coatings. Meanwhile, the mere addition of 8YSZ and 3YSZ in the Al₂O₃ matrix showed an increment (10.5% and 67.5%, respectively) in the scratch toughness compared to that of monolithic Al₂O₃ (2.37 MPa.m^0.5) coating.

开发了一种有效的基于Al ₂ O ₃的纳米复合涂层，以制造热障涂层（TBC）的顶层绝热层。在此，通过大气等离子喷涂制备基于Al ₂ O ₃的涂层，并使用渐进载荷刮擦研究刮擦性能。分析了碳纳米管（CNT），3 mol％和8 mol％Y ₂ O ₃稳定的ZrO ₂（分别为3YSZ和8YSZ）在逐步载荷刮擦过程中的刮擦机理和作用。调查显示，Al ₂ O ₃与整体式Al ₂ O ₃（0.128）相比，基于纳米的复合材料涂层具有较高的刮擦系数（0.165-0.219 ）。另外，整体式的Al ₂ ö ₃涂层显示体面的耐擦伤性（0.35毫米³ Ñ ^-1 米^-1相比3YSZ / 8YSZ和CNT）增强纳米复合材料（0.49-69毫米³ Ñ ^-1 米^-1）。这归因于硬度，断裂韧性以及增强材料与基体Al ₂ O ₃的结合的协同作用。。在YSZ和CNT增强的纳米复合材料中，薄片的粘附功为1.16–2.75×10 ³  J，比整体式Al ₂ O ₃（2.91×10 ³  J）低（最高2.5倍）。这归因于CNT与包含Al ₂ O ₃和YSZ的薄片的不良结合。此外，CNT可阻止纳米复合涂层的剥落，例如剥落和碎裂。然而，添加CNT会降低纳米复合涂层的耐刮擦韧性（1.05-2.04 MPa.m ^0.5）。它不支持CNT对涂层的划痕韧性的有效贡献。同时，仅在Al ₂ O中添加了8YSZ和3YSZ与整体式Al ₂ O ₃（2.37 MPa.m ^0.5）涂层相比，₃基体的划痕韧性增加（分别为10.5％和67.5％）。