| Affiliation: | 1.School of Chemistry and Chemical Engineering,Guangxi University,Nanning,P.R. China;2.Department of Physics,Xiangtan University,Hunan Province,P.R. China;3.Light Alloy Net Forming National Engineering Research Center, School of Materials Science and Engineering,Shanghai Jiaotong University,Shanghai,P.R. China |
| Abstract: | Based on the synchroshear mechanism, the formation of intrinsic stacking fault I 2 and twin-like stacking fault T 2 in C14 Laves phases has been modeled in detail and the generalised stacking fault energy curve of I 2 and T 2 for C14 Laves phase MgZn2 has been calculated from first-principles. The results demonstrate that the unstable stacking fault energy of I 2 by synchroshear is still very large, and the stable stacking fault energy of I 2 is higher in comparison with pure Mg implying that the formation of I 2 stacking fault in MgZn2 is difficult. Starting with the I 2 configuration, the T 2 stacking fault can be formed by an additional synchroshear. The unstable and stable stacking fault energies of T 2 are only slightly larger than those of I 2, implying that the formation of T 2 may be essentially similar to that of I 2. From the obtained generalised stacking fault energy, the relevant deformation mechanism of MgZn2 is also discussed. Finally, the electronic structure during synchroshear process is further studied. |
