Metastable phases and spinodal decomposition in Ti1-xAlxN system studied by ab initio and thermodynamic modeling, a comparison with the TiN-Si3N4 system
Metastable phases and spinodal decomposition in Ti1-xAlxN system studied by ab initio and thermodynamic modeling, a comparison with the TiN-Si3N4 system
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DOI：
10.1016/j.msea.2006.10.012
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发表时间：
2007-03-15
期刊：
影响因子：
6.4
通讯作者：
Veprek, S.
中科院分区：
文献类型：
--
作者：
Zhang, R. F.;Veprek, S.
使用Vienna Ab Intibal Simulation Package（VASP）计算了二进制HCP-和FCC-TIN，AIN和三元TI0.5AL0.5N相的二进制HCP-和FCC-TIN的总能量和晶格常数。然后，使用总能量的值来计算二进制HCP-和FCC-TIN的晶格稳定性。 AIN和三元Ti1-X的相互作用参数，基于半经验的热力学亚晶格模型。基于这些数据，为了讨论整个组合物范围内亚稳态三元hcp-和fcc-ti1-xalxn阶段亚稳态的三元相稳定性的吉布斯自由能图。将预测与PVD和CVD实验的公开结果进行了比较。计算出的晶格能和构造的吉布斯自由能图显示，与实验一致，可稳定的FCC-TI1-XALXN涂层可以轻松地将旋缺链分解为相干的FCC-TIN和FCC-ALN，但是有相对较大的障碍物，用于稳定的HCP-ALN的形成。与TIN-SI3N4系统的比较表明，由于该系统的混合能量要高得多，与Tin-Aln One相比，Spinodal分解也可能发生在该系统中，对于半晶格TIN和SI3N4阶段。 （c）2006 Elsevier B.V.保留所有权利。
The total energies and lattice constants of binary hcp- and fcc-TiN, AIN and ternary Ti0.5Al0.5N phases are calculated by ab initio method using the Vienna ab initio simulation package (VASP). The values of total energies are then used to calculate the lattice stabilities of binary hcp- and fcc-TiN. AIN and the interaction parameter of ternary Ti1-x,AlxN phases on the basis of the semiempirical, thermodynamic sub-lattice model. Based on these data, the Gibbs free energy diagram of the immiscible quasi-binary TiN-AlN system are constructed in order to discuss the relative phase stability of the metastable ternary hcp- and fcc-Ti1-xAlxN phases over the entire range of compositions. The prediction is compared with the published results from PVD and CVD experiments. The calculated lattice energy and the constructed Gibbs free energy diagram show, in agreement with the experiments, that metastable fcc-Ti1-xAlxN coatings can easily undergo spinodal decomposition into coherent fcc-TiN and fcc-AlN, but there is a relatively large barrier for the formation of the stable hcp-AlN. A comparison with the TiN-Si3N4 system shows that, due to the much higher de-mixing energy of this system as compared to the TiN-AlN one, spinodal decomposition may occur in that system also for semicoherent TiN and Si3N4 phases. (c) 2006 Elsevier B.V. All rights reserved.