Impact Factor3.7

DOI number:10.1016/j.mtcomm.2022.105039

Journal:Materials Today Communications

Funded by:国家自然科学基金

Key Words:Heat -resistant steel；Creep damage；Microstructure degradation；Potentiodynamic polarization

Abstract:Using the electrochemical detection technique, this work dealt with the microstructure evolution during the creep of a modified 9Cr-1Mo (P91) heat-resistant steel. In order to prepare specimens with various degradation states, a series of interrupted creep tests was firstly carried out at 600 celcius with 165 MPa. Then, the electrochemical measurement and microstructure observation were employed to characterize the resultant degradation of crept specimens, respectively. The obtained results showed that the electrochemical parameters of critical passivation current density and self-corrosion current density are very sensitive to the microstructure evolution during creep of P91 steel. During the primary creep stage, the rapid decrease of both parameters occurs, mainly resulting from the remarkable decrease of mobile dislocation density. During the secondary and tertiary creep stages, however, above parameters monotonically increase under the combined action of precipitates and high angle grain boundaries (HAGBs). In addition, it is further suggested that based on this initial study, there may be scope to use electrochemical detection technology as a nondestructive tool to monitor microstructural evolution during creep.

Indexed by:Journal paper

Discipline:Engineering

Document Type:J

Volume:34

Page Number:105039

Translation or Not:no

Date of Publication:2023-03-01

Included Journals:SCI