Fan et al. have reported the fabrication of highly dense (≥ 98%) thin-walled Al2O3-YAG-ZrO2 (AYZ) eutectic ceramic using LENS technique. The as-synthesized state of the material shows a cellular microstructure with the interpenetration of three phases (namely, α-Al2O3, YAG and ZrO2) . In addition, a morphological transition from planar to cellular eutectic microstructure (along BD) was reported for every deposited layer . Fig. shows a scanning transmission electron microscopy (STEM)-high-angle annular dark field (HAADF) image of AYZ ceramic in as-fabricated condition . Figs. ) shows the corresponding STEM-Energy Dispersive Spectroscopy (EDS) maps for different elements: Al, Y, Zr and O. The dark, grey and bright phases in STEM-HAADF image (Fig. ) correspond to α-Al2O3, YAG and cubic ZrO2 phases respectively, as is also evident from Figs. ) and Table . 1 . Besides, from Figs. ) and Table. 1, it may be observed that ~18 mol.% Y2O3 is dissolved in ZrO2 in as-fabricated condition indicating that cubic ZrO2 is stabilised by Y 3+ during cooling and solidification (during LENS) . An irregular interpenetration of fibrous eutectic structure was also reported to occur along the boundary region of the fabricated specimens . This was attributed to a much higher rate of solidification at the boundary region as compared to that within the sample interior . In addition, the orientation relation between the three phases at the interior of LENSed samples was obtained as <0001>Al2O3 // <001>YAG // <001>ZrO2 (with a slight deviation of ~3.5° between {001}YAG with {11-20}Al2O3 and {001}ZrO2 obtained using Transmission Kikuchi Diffraction (TKD) technique and verified with High-resolution Transmission Electron Microscopy (HRTEM) imaging of a triple junction formed between Al2O3, YAG and ZrO2 phases (Fig. ) . The aforementioned deviation may be attributed to a competitive effect between interfacial energy and growth kinetics . For instance, the lower interfacial energy of Al2O3/ZrO2 interface (~ 0.74 J/m 2 ) as compared to that for Al2O3/YAG interface with an interfacial energy ~3.23 J/m 2 may be attributed to a better parallel nature of {11-20} Al2O3 //{001} ZrO2 when compared with that for {11-20} Al2O3//{001} YAG , . Fig. shows an SEM image of the longitudinal section of LENSed AYZ specimen subjected to TKD analysis along BD . The growth direction of the cellular eutectics remains the same as that for the transverse section of AYZ samples i.e. <0001>Al2O3 // <001>YAG // <001>ZrO2 . However, unlike the transverse section, the longitudinal section also shows YAG crystals with minor growth direction as <111> . This may be attributed to the deviation of these crystals (present mainly near cellular boundaries as shown in Fig. ) from their habit planes and subsequent heading towards cellular boundary instead of remaining parallel with the cell growth direction. A similar observation has been reported for Al2O3-ZrO2 cellular eutectic by Sayir and Farmer and for Ni-Al-V eutectic alloys by Milenkovic et al. . In part (a), BD abbreviates for building direction.