J. Mater. Sci. Technol. ›› 2025, Vol. 228: 125-136.DOI: 10.1016/j.jmst.2025.01.006

• Research article • Previous Articles     Next Articles

Correlation between metastable pitting and structural heterogeneity in Co-based metallic glasses

Haoran Maa, Dongxue Hanb, Chunyang Mua, Feixiong Maoc, Aina Hea,d, Yaqiang Donga,d, Deren Lie,*, Qikui Mana,d, Baogen Shena, Jiawei Lia,d,*   

  1. aZhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo 315201, China;
    bAerospace Additive Manufacturing Technology (Beijing) Co., Ltd. Beijing 100074, China;
    cKey Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China;
    dUniversity of Chinese Academy of Sciences, Beijing 100049, China;
    eSchool of Electrical Engineering, Beijing Jiaotong University, Beijing 100044, China
  • Received:2024-09-12 Revised:2024-12-23 Accepted:2025-01-02 Published:2025-09-01 Online:2025-09-01
  • Contact: *E-mail addresses: derenli@bjtu.edu.cn (D. Li), lijw@nimte.ac.cn (J. Li)

Abstract: By employing micrometer-diameter microelectrodes, the metastable pitting corrosion behavior of Co68.15Fe4.35Si12.5B12Cr3 metallic glasses (MGs) exposed to 0.6 mol/L NaCl solution was investigated to clarify the correlation between metastable pitting and structural heterogeneity in MGs. Thermally induced degeneration of structural heterogeneity inhibits the initiation, decelerates the growth kinetics, and accelerates the repassivation kinetics of metastable pits while also decreasing the probability of transition from metastability to stability. This enhanced resistance to pitting corrosion is attributed to a reduction in active pitting precursor sites and a decrease in electrochemical activity caused by the structural homogenization of MGs.

Key words: Metallic glasses, Structural heterogeneity, Metastable pitting, Pitting kinetics