Abstract
In order to develop a creep life assessment technique for a directionally solidified Ni-base superalloy CM247LC used in advanced gas turbine blades, changes in electrochemical properties of CM247LC due o creep have been investigated. The electrochemical polarization technique has been applied to creep-ruptured and creep-interrupted specimens under various creep conditions in order to examine a detectability of creep damage. Experimental results on electrochemical polarization measurements revealed that the peak current density "Ip" and "Ipr" which appeared at a specific potential during potentiodynamic polarization reactivation measurements in dilute glyceregia solution linearly increased with a life fraction in early stage of the creep life (t/tr=0.3). The increases in Ip and IIr mainly corresponded to increases in preferential dissolution rate of γ′ phase at γ/γ′ interface. This preferential dissolution was considered as a result from change in chemical composition of y phase at ylY interface which may be attributable to creep damage accumulation. As a consequence, the creep life fraction can be estimated with high accuracy by the electrochemical technique.
| Translated title of the contribution | Creep life prediction of Ni-base superalloy used in advanced gas turbine blades by electrochemical method |
|---|---|
| Original language | Japanese |
| Pages (from-to) | 1147-1155 |
| Number of pages | 9 |
| Journal | Nihon Kikai Gakkai Ronbunshu, A Hen/Transactions of the Japan Society of Mechanical Engineers, Part A |
| Volume | 65 |
| Issue number | 633 |
| DOIs | |
| Publication status | Published - 1999 |
ASJC Scopus subject areas
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering