start-ver=1.4
cd-journal=joma
no-vol=59
cd-vols=
no-issue=6
article-no=
start-page=1314
end-page=1328
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2024
dt-pub=20240310
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Wetting property of Fe‐S melt in solid core: Implication for the core crystallization process in planetesimals
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=In differentiated planetesimals, the liquid core starts to crystallize during secular cooling, followed by the separation of liquid–solid phases in the core. The wetting property between liquid and solid iron alloys determines whether the core melts are trapped in the solid core or they can separate from the solid core during core crystallization. In this study, we performed high-pressure experiments under the conditions of the interior of small bodies (0.5–3.0 GPa) to study the wetting property (dihedral angle) between solid Fe and liquid Fe-S as a function of pressure and duration. The measured dihedral angles are approximately constant after 2 h and decrease with increasing pressure. The dihedral angles range from 30° to 48°, which are below the percolation threshold of 60° at 0.5–3.0 GPa. The oxygen content in the melt decreases with increasing pressure and there are strong positive correlations between the S + O or O content and the dihedral angle. Therefore, the change in the dihedral angle is likely controlled by the O content of the Fe-S melt, and the dihedral angle tends to decrease with decreasing O content in the Fe-S melt. Consequently, the Fe-S melt can form interconnected networks in the solid core. In the obtained range of the dihedral angle, a certain amount of the Fe-S melt can stably coexist with solid Fe, which would correspond to the “trapped melt” in iron meteorites. Excess amounts of the melt would migrate from the solid core over a long period of core crystallization in planetesimals.
en-copyright=
kn-copyright=

en-aut-name=MatsubaraShiori
en-aut-sei=Matsubara
en-aut-mei=Shiori
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=TerasakiHidenori
en-aut-sei=Terasaki
en-aut-mei=Hidenori
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=YoshinoTakashi
en-aut-sei=Yoshino
en-aut-mei=Takashi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=UrakawaSatoru
en-aut-sei=Urakawa
en-aut-mei=Satoru
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

en-aut-name=YumitoriDaisuke
en-aut-sei=Yumitori
en-aut-mei=Daisuke
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=5
ORCID=

affil-num=1
en-affil=Department of Earth Sciences, Graduate School of Science and Technology, Okayama University
kn-affil=

affil-num=2
en-affil=Department of Earth Sciences, Graduate School of Science and Technology, Okayama University
kn-affil=

affil-num=3
en-affil=Institute for Planetary Materials, Okayama University
kn-affil=

affil-num=4
en-affil=Department of Earth Sciences, Graduate School of Science and Technology, Okayama University
kn-affil=

affil-num=5
en-affil=Department of Earth Sciences, Graduate School of Science and Technology, Okayama University
kn-affil=
END