This paper proposes a method for alloy composition screening using the creep property of a single crystal (SC) for designing new Ni-base powder metallurgy (P/M) turbine disc superalloys. A commercial Ni-base disc alloy, U720Li®, a Ni-Co-base disc alloy, TMW-4M3, and a Ni-base conventionally cast alloy, TM-47, were selected for investigation. Their SC and P/M samples were prepared such that their γ/γ′ structures were similar. Moreover, tensile creep tests were performed on SC samples, and compressive creep tests were performed on SC and P/M samples. The tensile creep test results of SC samples at 1073 K (800 °C) and 735 MPa indicate that 0.2 and 1 pct creep times, as well as rupture life, are long in the order of TM-47 SC, TMW-4M3 SC, and U720Li SC. These results simulate the intragranular creep resistances of the corresponding P/M alloys. Furthermore, there is no significant difference in 0.2 and 1 pct compressive creep times between the SC and P/M samples of each alloy. Additionally, the 0.2 and 1 pct creep times of tensile and compressive creep tests of every alloy had an identical order. Therefore, alloy composition screening using SC creep property enables the design of new disc alloys with excellent creep resistance.

本文提出了一种利用单晶蠕变特性筛选合金成分的方法，以设计新型的镍基粉末冶金（P / M）涡轮盘式高温合金。选择了商用镍基圆盘合金U720Li®，镍钴基圆盘合金TMW-4M3和镍基传统铸造合金TM-47进行研究。他们的SC和P / M样品的制备使其γ / γ的结构相似。此外，对SC样品进行了拉伸蠕变测试，对SC和P / M样品进行了压缩蠕变测试。SC样品在1073 K（800°C）和735 MPa下的拉伸蠕变测试结果表明，蠕变时间0.2和1 pct以及断裂寿命长于TM-47 SC，TMW-4M3 SC，和U720Li SC。这些结果模拟了相应P / M合金的晶内抗蠕变性。此外，每种合金的SC和P / M样品之间的0.2和1 pct压缩蠕变时间没有显着差异。另外，每种合金的拉伸和压缩蠕变测试的0.2和1 pct蠕变时间具有相同的顺序。因此，利用SC蠕变性能进行合金成分筛选可以设计出具有优异抗蠕变性的新型圆盘合金。