Effects of TCP and creep cavity on creep life in the rafting regime for Ru-containing Nickel-based single crystal superalloys

Abstract

Ru is crucial in improving creep properties in Nickel-based single-crystal superalloys. The effect of Ru content on the creep behavior of nickel-based single-crystal superalloy was studied. Ru exhibits unprecedented mechanical properties, increasing the creep life at 1120 °C but decreasing it at 1180 °C. This is due to the competition in the stress concentration formed between the topologically close-packed phases and the creep cavity. They are both related to the dissociation of the γ^′ phase. The effect of oxidation caused by the addition of Ru is lower than these two factors. This work helps to recognize the comprehensive effect of Ru and can provide guidance for alloy design in the future.

GRAPHICAL ABSTRACT

IMPACT STATEMENT

The study first revealed that adding Ru can reduce the creep life at high temperatures. The competition mechanism between the topologically closed-packed phase and the creep cavity is established.

KEYWORDS:

• Superalloy
• Ru element
• creep
• microstructure
• diffusion

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the National Key Research and Development Program of China (No. 2021YFA1200201), Natural Science Foundation of China (Nos. 51988101, 91860202, 52171001, 52071003, 52001297), General Program of Science and Technology Development Project of R&D Program of Beijing Municipal Education Commission KM202210005003, Beijing Outstanding Young Scientists Projects (BJJWZYJH01201910005018), National Key Research and Development Program of China (No. 2021YFA1200201), Beijing Nova Program (Z211100002121170), ‘111’ project (DB18015).