中文摘要：

研究了锻态Ni60Ti形状记忆合金在750~850℃的空气中的高温循环氧化行为,采用OM、XRD、SEM和EDS对氧化层的组织和物相进行分析。结果表明,随着氧化温度升高,合金氧化速度加快,氧化增重增大。在循环氧化前期（0~30h）,氧化速度较快,反应级数n值均小于2;在循环氧化中后期（30~102h）,750℃和800℃的n值大于2,而850℃时由于氧化层开裂、剥落,导致其n值（1.927）小于2。随着氧化温度升高和时间延长,由表及里,形成了4层结构的氧化层,依次为：TiO2、TiO2＋NiTiO3、TiO2＋NiTiO3＋Ni、Ni3Ti。

英文摘要：

The cyclic oxidation behavior of as-forged Ni60 Ti alloy was investigated at 750~850 ℃in air environment.The cross-sectional morphologies and phase constituent of the alloy were observed by optical microscope（OM）,X-ray diffractometry（XRD）,scanning electron microscopy（SEM）and energy dispersive spectroscopy（EDS）.The results reveal that with increasing in temperature,oxidation rate and weight-increment are increased.At the early stage of the cyclic oxidation,values of reaction order（n）are less than 2.At the late stage,the values of nat 750℃and 800℃are more than 2,while it is 1.927 at 850℃as a result of oxidation layer cracking and spalling.With temperature and duration increase,a four-layered structure oxidation layer is composed as follows from surface to inner layer：pure TiO2 rutile,a layer of mixture of TiO2 and NiTiO3,a layer of mixture of TiO2,NiTiO3 and Ni,Ni3 Ti layer.