Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5456540 | Materials Science and Engineering: A | 2016 | 19 Pages |
Abstract
Nanoindentation tests were performed on single crystal Ni-based superalloy at temperatures ranging from 20 °C to 800 °C in inert environment. Load-displacement curves at temperatures higher than 500 °C exhibit obvious creep inferred by increasing displacements at load-holding segments. Load-displacement curves obtained at 800 °C also display negative unloading stiffness. Examination of the microstructure beneath the indented area using Transmission Electron Microscope (TEM) reveals abundant dislocation piling up as well as oxide formation on the substrate. A method considering the creep effect is proposed to calculate the reduced modulus. In addition, a dimensionless ratio relating indentation depth and oxide film thickness is introduced to explain the oxidation effect on the mechanical properties derived from the load-displacement curves.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
Yan Li, Xufei Fang, Siyuan Lu, Qingmin Yu, Guohui Hou, Xue Feng,