Page 295 - Read Online

Page 12 of 23 Zhou et al. Microstructures 2023;3:2023043 https://dx.doi.org/10.20517/microstructures.2023.38

Figure 7. Cryo-APT observations of hydrogen trapping in metal carbides in ferrite steels. (A) APT analyses of a deuterium-charged
ferritic steel containing V-Mo carbides. Reproduced with the permission of Ref. [40] Copyright 2017, The American Association for the
Advancement of Science. (B) APT analyses of a deuterium-charged ferritic steel containing NbC. Reproduced with the permission of
Ref. [34] Copyright 2020, The American Association for the Advancement of Science.

Figure 8. APT analyses deuterium-charged Al-Zn-Mg-Cu alloys. (A) 2-D slice views that include Al Zr dispersoids and (B) 1-D
3
concentration profile from the arrow in (A). (C) 2-D slice views that include Al CuMg S phase and (D) 1-D concentration profile from
2
the arrow in (C). Scale bars in (A, C) represent 30 nm. Reproduced with the permission of Ref. [79] Copyright 2022, Springer Nature.
come into contact with water (H O) or oxidize in a moist environment, hydrogen can be produced as a by-
2
product during the oxidation process. This hydrogen can then permeate the metal matrix and lead to
hydrogen embrittlement, compromising the mechanical properties of materials . To enhance the
[78]
microstructures of aluminum alloys and improve their resistance to hydrogen attack, it is crucial to
investigate how hydrogen can be trapped within the material. Using APT plays a vital role in this endeavor.

Recently, Zhao et al. achieved success in using cryo-FIB to fabricate cryo-APT specimens and measure
trapped deuterium in aluminum alloys . The team provided the first direct observations of hydrogen
[79]
trapping in Al Zr dispersoids (shown in Figure 8A and B) and the Al CuMg second phase (commonly
3
2