The high temperature creep properties of next generation cast and wrought AD730 superalloy have been investigated taking into consideration three microstructural parameters: the grain size, the presence of grain boundaries and the γ′ precipitates size and distribution. Definitive analysis of the influence of the grain boundaries and γ′ precipitates size distribution has been enabled by the study of single crystalline versions of the polycrystalline alloys studied. At high temperature (equal to or in excess of 850 °C), the grain size controls creep properties. Comparisons between polycrystalline and single crystalline specimens indicate that the grain boundaries provide a strengthening effect, especially in the small strain regime. At intermediate temperature (700 °C), the γ′ precipitates size is the main creep-rate controlling parameter. In this temperature domain, creep strength seems to be mainly controlled by dislocation motion. A very striking grain boundary strengthening mechanism is observed at small creep strain and intermediate temperature.

考虑到三个微观结构参数，研究了下一代铸造和锻造AD730高温合金的高温蠕变性能：晶粒尺寸，晶界的存在以及γ'析出物的尺寸和分布。通过研究所研究的多晶合金的单晶形式，可以对晶界和γ'沉淀尺寸分布的影响进行确定的分析。在高温下（等于或超过850°C），晶粒度控制蠕变性能。多晶和单晶试样之间的比较表明，晶界提供了强化作用，尤其是在小应变状态下。在中间温度（700°C）下，γ'沉淀物尺寸是主要的蠕变速率控制参数。在此温度范围内，蠕变强度似乎主要受位错运动控制。在较小的蠕变应变和中等温度下，观察到非常明显的晶界强化机制。