화학공학소재연구정보센터
Journal of Materials Science, Vol.56, No.3, 2559-2571, 2021
Theoretical calculation and experimental investigation on NbC refined by CeAlO(3)in hypereutectic Fe-Cr-C-Nb hardfacing alloy
The interface properties of CeAlO3(110)/NbC (111) were calculated by the first-principles and the refinement of CeAlO(3)on NbC in hypereutectic Fe-Cr-C-Nb hardfacing alloy was demonstrated by experiments. The calculation results show that the mismatch of CeAlO3(110)/NbC (111) is 7.2%, which indicates that the interface between CeAlO3(110) and NbC (111) is a semi-coherent interface. Then, 11 layer CeAlO-terminated CeAlO3(110) surface was selected to build interface with NbC (111) surface, whose surface energy is 0.380 eV/angstrom(2). Because of the instability of O-terminated CeAlO3(110) surface, its surface energy cannot achieve convergence. 6 kinds of interfaces between CeAlO3(110)/NbC (111) were constructed, in which, interface-3 is the most stable with strong ionic and covalent bonds. Theoretically, CeAlO3 can act as the heterogeneous nucleation site for NbC. The experimental results show that the (Cr, Fe)(7)C-3, NbC and gamma-Fe phases exist in hypereutectic Fe-Cr-C-Nb-CeAlO(3)hardfacing alloys. When CeAlO(3)was added into the alloy, NbC can be refined.