|
|
|
| In-situ Corrosion Characterization of API X80 Steel and Its Corresponding HAZ Microstructures in an Acidic Environment |
| Li-wei WANG1,2,Xiao-gang LI1,Cui-wei DU1,Peng ZHANG2,Yi-zhong HUANG3 |
1. Corrosion and Protection Center, University of Science and Technology Beijing, Beijing 100083, China
2. Pipeline Research Institute of CNPC, Langfang 065000, Hebei, China
3. School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore |
|
|
|
|
Abstract During heat treatment processing, microstructures of heat affected zone (HAZ) were formed in X80 pipeline steel. After observation by optical microscopy, scanning electron microscopy and transmission electron microscopy, microstructure of the as-received X80 steel was confirmed to be acicular ferrite, while the microstructures of quenched, normalized and annealed X80 steels were lath bainite, granular ferrite and quasi-polygonal ferrite, respectively. After immersion in the simulated acidic soil solution for 48 h, corrosion rates of these four steels were determined by mass loss measurements and corrosion products were examined by Raman spectroscopy and X-ray photoelectron spectroscopy. Scanning vibrating electrode technique was used to characterize the micro-galvanic corrosion behaviors of the synthetic bimetallic electrodes which were formed by coupling each of the simulated HAZ microstructures with the as-received steel in direct physical and electric contact. It is demonstrated that the as-received steel acts as cathode in the as-received/quenched and as-received/normalized couples, while the annealed steel acts as cathode when coupling with the as-received steel. The distinction of current density between the galvanic couples reduces with prolonging the immersion time.
|
|
Received: 29 September 2013
Published: 02 February 2015
|
| Fund:National Outstanding Youth Science Foundation of China;��973�� National Basic Research Project of China |
|
Corresponding Authors:
Li-Wei Wang
E-mail: ustbwangliwei@126.com
|
|
|
|
| [1] |
Ying Ci,*,Zhan-zhan Zhang. Simulation study on heat-affected zone of high-strain X80 pipeline steel[J]. Chinese Journal of Iron and Steel, 2017, 24(9): 966-973. |
| [2] |
Ze-an Lv,,Hong-wei Ni,,*,Hua Zhang,,Cheng-song Liu,,**. Evolution of MnS inclusions in Ti-bearing X80 pipeline steel[J]. Chinese Journal of Iron and Steel, 2017, 24(6): 654-660. |
| [3] |
Kun LING,Zheng-dong WANG,Fu-zhen XUAN. Numerical Studies of Estimation of Fracture Parameters for Mismatched Welded Joints with HAZ Cracks[J]. Chinese Journal of Iron and Steel, 2015, 22(9): 846-851. |
| [4] |
Chuan CHEN,Shu-sen CHENG,Xi-bin GUO. Hazard Control of NOx in Hot Stove[J]. Chinese Journal of Iron and Steel, 2014, 21(3): 306-311. |
| [5] |
CHEN Xiao-wei,,LIAO Bo,QIAO Gui-ying,GU Yu,WANG Xu,,XIAO Fu-ren. Effect of Nb on Mechanical Properties of HAZ for High-Nb X80 Pipeline Steels[J]. Chinese Journal of Iron and Steel, 2013, 20(12): 53-59. |
| [6] |
KONG De-jun,WU Yong-zhong,LONG Dan. Stress Corrosion of X80 Pipeline Steel Welded Joints by Slow Strain Test in NACE H2S Solutions[J]. Chinese Journal of Iron and Steel, 2013, 20(1): 40-46. |
|
|
|
|
2015, Vol. 22 
