Characterization of Microstructures and Mechanical Properties in Nickel-base Superalloy upon Creep Test

Sijia Liu1,
Seung-Wan Yang2, Tae-Hee Ok2, Hong Kyu Kim3, Sung-Seop Hong3, Keesam Shin1

1Advanced Metallurgical and Materials Engineering, Changwon National University, Changwon 51140, Korea

2Hanwha Aerospace, 1204, Changwon-daero, Seongsan-gu, Changwon-si, Gyeongsangnam-do, Korea

3Agency for Defense Development, 462 Jochiwon-gil Yuseong-gu Daejeon, Korea

E-mail: keesamgg@gmail.com

In this study, we characterized the microstructures and mechanical properties of Nickel-base superalloy upon creep test. Nickel-base superalloy holds great room for development due to its microstructure characteristic, i.e., 1) multiple elements can be added to superalloys for high temperature stability; 2) forming of intermetallic compound γ' phase as a strengthening phase. To understand microstructural evolution of superalloy after creep test, we performed preliminary heat treatment experiment on two Nickel-base alloy and another two Nickel-base alloy was tested under 650°C, 870Mpa and 650°C, 100Mpa for 28h, separately. Microstructural evolution and precipitate behavior were investigated. Various analytical methods were used including optical microscopy (OM), scanning electron microscopy (SEM), electron backscattered diffraction (EBSD) and transmission electron microscopy (TEM) for microstructure analysis. X-ray diffraction (XRD) were used to measure the lattice parameter during experimental procedure.

Keyword: nickel-base superalloy, creep test, microstructure, mechanical properties