采用高通量的合金设计方法设计一种新型镍基单晶高温合金CSU.B2,并对该合金进行了一系列的研究。结果表明:该合金在铸态下树枝晶分布均匀,枝晶间距约为500gm,没有三次枝晶出现。通过对合金进行固溶和时效处理,合金中的γ’析出相呈现方块状,平均颗粒尺寸为0.5~0.8μm。在1100和1150℃下对合金的抗氧化性能进行研究发现,试样单位面积质量随时间的变化遵循类抛物线的规律,在氧化层的下面都存在着γ’相消失的区域。最后对合金的高温拉伸性能进行了表征,在760℃时,合金的屈服强度为706MPa;在980℃时,合金的屈服强度为484MPa。在两个温度下,试样的断裂为两种不同的机制。
A new nickel-base single crystal superalloy named CSU-B2 was designed by high-throughput alloy design method and a series of investigations were done to characterize the superalloy. The results show that the primary dendrites are uniformly distributed and the spacing size in the as-cast alloy is about 500 μm, where tertiary dendrite is absent. After solution and ageing treatments, the γ' prime precipitates are cuboidal-shaped and the average size is 0.5-0.8 μm. The oxidation-resistance property of the new alloy is evaluated at 1100 and 1150 ℃, the results show that the oxide growth of the new alloy obeys the parabolic law for both under isothermal and cyclic oxidation, and there both have a y' free zone under the oxide scale. The yield strengths under the temperature of 760 and 980 ℃ are measured to be 706 and 484 MPa, respectively, and two different mechanisms govern the failure processes.