1College of Energy, Xiamen University, Xiamen 361005 2Laboratory of Dielectric Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 3College of Physical Science and Technology, Xiamen University, Xiamen 361005
Abstract：Apatite ceramics Ca$_{10}$(PO$_{4})_{6}$$X_{2}$ ($X=$F, OH) were prepared by the standard solid state sintering method and irradiated with He ions under a fluence of $5\times 10^{16}$ ions/cm$^{2}$ at 450 $^{\circ}\!$C. Irradiation induced formation and growth of the He bubbles were observed by a transmission electron microscope. Hydroxyapatite Ca$_{10}$(PO$_{4})_{6}$(OH)$_{2}$ and fluoroapatite Ca$_{10}$(PO$_{4})_{6}$F$_{2}$ with different He bubble morphologies indicate the influence of OH$^{-}$/F$^{-}$ substitution on the He-ion annealing efficiency, as well as the structure itself, which affects the process of He bubble evolution and formation. The grain boundaries also act as sinks to accumulate He bubbles. No obvious irradiation damage but slight intensity reduction and left shift of diffraction peaks were observed according to the grazing incidence x-ray diffraction and Raman spectra characterizations, indicating that defects of interstitials and vacancies were generated.
Weber W J, Ewing R C, Catlow C R A, de la Rubia T D, Hobbs L W, Kinoshita C, Matzke H, Motta A T, Nastasi M, Salje E K H, Vance E R and Zinkle S J 1998 J. Mater. Res.13 1434
2020, Vol. 37 
