摘要：TiAl基金属间化合物具有低密度、高熔点以及较高的高温比强度，因此TiAl基金属间化合物被认为是最有应用潜力的新一代航空及高温结构材料，其研究前景一直被众多学者看好。但由于Ti和Al形成的氧化物具有相似的稳定性，故在TiAl合金表面不能形成连续致密的Al2O3保护膜，而是形成与TiO2的混合氧化膜，因此在800℃以上长期使用时，合金高温抗氧化性能不足，这一弱点已严重影响其应用。本文在利用马弗炉（SXL）、XRD射线衍射仪（XRD）、扫描电镜（SEM）、能谱仪（EDS）对合金样品进行氧化实验，研究TiAl合金的高温氧化行为。结果表明，TiAl基合金在氧化实验完成后，其主要氧化膜组成成分为TiO2以及Al2O3。氧化层表面为棒状TiO2晶粒堆垛且不致密，冷却过程中部分表层氧化膜开裂或剥落，脱落后的内层为多孔，疏松的TiO2与Al2O3的混合氧化物，再向内为富Al2O3薄层。70111

毕业论文关键词：金属间化合物；高温氧化；TiAl合金 

Study on High Temperature Oxidation Behavior of TiAl Alloy

Abstract：TiAl-based intermetallic compounds are considered to be the most promising new generation of aerospace and high temperature structural materials, and their research prospects have been favored by many scholars. However, since the oxides formed by Ti and Al have similar stability, a continuous dense Al2O3 protective film can not be formed on the surface of TiAl alloy, but a mixed oxide film with TiO2 is formed. Therefore, when the oxide is used at 800 ° C for a long period of time, Antioxidant performance is insufficient, this weakness has seriously affected its application. In this paper, the oxidation experiments of alloy samples were carried out by using muffle furnace (SXL), XRD, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) to study the high temperature oxidation behavior of TiAl alloy. The results show that the composition of the TiAl base alloy is TiO2 and Al2O3 after the oxidation experiment is completed. The oxide layer on the surface of the oxide layer is not dense, and some of the surface oxide film is cracked or peeled off during the cooling process. The inner layer after the shedding is porous, the mixed oxide of TiO2 and Al2O3 is inward,and then inward is rich in Al2O3 layer.

Key words：Intermetallic compounds；High temperature oxidation；TiAl alloy

目录

1 绪论 1

1.1 高温合金 1

1.2 高温合金的种类 2

1.2.1 铁基合金 2

1.2.2 镍基合金 2

1.2.3 钴基合金 3

1.3 金属间化合物 3

1.4 金属氧化 3

1.5 纯金属氧化 4

1.6 合金氧化 5

1.7 常见元素对高温氧化行为的影响 5

1.8研究目的和意义 6

2 试验材料与方法 7

2.1 实验材料 7

2.2  实验设备及材料 8

3 实验结果与讨论 11

3.1 X射线衍射物相分析 11

3.2 表面形貌分析 12

3.3 能谱分析 18

3.4 截面形貌分析 20

3.5 讨论 21

3 结论