研究了添加3.5%铼对钴基和镍基MCr Al Y涂层合金在1000℃和1150℃氧化行为的影响。采用SEM、EPMA和XRD分析了合金显微结构、合金及氧化物的元素分布和相组成。通过测量在不同氧化时间和氧化温度下的样品增重获得氧化动力学曲线。结果表明,在两种合金中添加Re增加了β相的体积分数,并使Cr-Re相析出。同时,Re也降低了两种合金的氧化膜生长速率,而且在较低温度下(1000℃)降低效果更为显著。两种含铼合金均生成了更为均匀的Al2O3氧化膜和少量的尖晶石,合金中Cr-Re相的存在抑制了尖晶石氧化物的生长。
The effects of 4 wt% rhenium （Re） addition on isothermal oxidation behavior of Tribaloy T-800 alloy have been studied at 800 °C and 1 000 °C in air. At 800 °C,T-800 shows nonuniform oxidation between dendritic and eutectic areas. Re addition clearly promotes the nonuniform oxidation,leading to considerably higher mass gains than that of T-800 at this temperature. At 1 000 °C exposure,the thickness of scale on T-800 increases significantly,accompanied by severe scale spallation during cooling to room temperature. On the contrary,T-800Re shows a marked decrease of oxide growth rate compared to the linear one of T-800 at 1 000 °C. The scale adhesion is also improved with Re addition at this higher temperature. Therefore,the role of Re depends on the exposure temperature. Re addition gives high oxidation rate at 800 °C,however,the excellent oxidation resistance is obtained by the addition of Re at a higher temperature of 1 000 °C.
