摘要
利用海绵钛、高纯铝与TiC/Al中间合金反应,采用非自耗电弧熔炼工艺,原位合成Ti2AlC/Ti-40Al复合材料。研究复合材料在900℃空气中的恒温氧化行为,分析不同的增强体含量对复合材料氧化动力学行为的影响,并通过SEM、EDS及XRD对氧化层的表面形貌、成分及横断面的显微结构进行分析。结果表明,复合材料的氧化动力学曲线介于抛物线和对数规律之间,且随着碳化物含量的增加,复合材料的抗氧化性呈下降趋势。研究发现,氧化表面为堆砌生长的柱状六方晶,主要为金红石型的TiO2;氧化断面为明显的三层结构,最内层氧化膜基本上是在碳化物颗粒周围产生的,中间层为Al2O3和TiO2的混合物层,外层主要为TiO2。
The in-situ synthesized Ti2AlC/Ti-40Al matrix composite were prepared by non-consumable arc melting technique with the reaction of titanium sponge, high purity aluminum and TiC/Al inter＇alloy. The isothermal oxidation behavior of the composite at 900℃ in air was investigated. The effects of reinforcement contents on oxidation behavior of the composite were analyzed. The surface morphology and cross-section microstructure of the oxidation scale were observed by SEM, EDS and XRD. The results show that the isothermal oxidation kinetic curves of the composite follow the law between parabolic law and logarithmic law. The oxidation resistance of the composite decreases with carbide content increasing. The surface morphologies are mainly cylindrical hexagonal and consist of rutile TiO2. The cross-section morphologies are typical three-layer structure. The inner layer occurs around the carbide particles and the outer layer is a thinner Ti-rich layer, while the middle layer is a thicker mixture-layer of Al2O3 and TiO2. The outer layer is mainly TiO2.
出处
《热加工工艺》
CSCD
北大核心
2008年第10期37-40,共4页
Hot Working Technology
