Work

Oxidation behavior of PM-HIPed Alloy 625 in high-temperature supercritical carbon dioxide

Year: 2025

Type: article

Abstract: • The oxidation behavior of PM-HIPed Alloy 625 in S-CO 2 environments was studied. • The ground surface oxidized faster than the polished surface. • δ -phase precipitation occurred in the sub-surface layer due to element segregation. • A greatly denser δ -phase was observed on ground surface due to accelerated Cr diffusion. • NbC particles tend to form hollow-shell oxides when exposed on the surface. Oxidation behavior of PM-HIPed Alloy 625 with polished and ground surfaces in supercritical CO₂ was investigated. The polished surface formed an outer Fe-rich oxide layer and an inner Cr-rich oxide layer, whilst the ground surface developed a thicker, continuous chromia layer. δ -phase precipitation occurred in the sub-surface layer due to element segregation caused by oxidation. A greatly denser δ -phase was observed on the ground surface due to accelerated Cr diffusion by the deformation layer. In addition, NbC particles tend to be fully oxidized when exposed on the surface, forming a hollow-shell structure.

Source: Corrosion Communications

DOI: 10.1016/j.corcom.2025.03.002

Authors: Zelong Luo, Chaochao Xue, Chaowei Guo, Litao Chang, En-Hou Han, Wenjun Kuang

Institutions: Xi'an Jiaotong University, South China University of Technology, Chinese Academy of Sciences, Shanghai Institute of Applied Physics

Language: English

Topic: High-Temperature Coating Behaviors

Subfield: Aerospace Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $1,800

Funders: Xi'an Jiaotong University, National Natural Science Foundation of China