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Hydrogen as a future alternative to fossil energy, vital energy, need effective storage media. The use of hydrogen storage materials is the use of hydrogen storage is an important part. And other metal hydrogen storage alloy, having a body-centered cubic (BCC) solid solution of large hydrogen storage alloy theory, the hydrogen absorption at room temperature fast, safe. However, to explore the high-performance multi-alloyed solid solution composition makes it difficult, at present basically depends on a lot of experiments to explore. Solid solution of solute atoms in the alloy are arranged as chemical short-range order, can use local polyhedra (clusters) of solute elements to describe the interaction between the matrix metal. Therefore, the study can be amorphous clusters BCC structure theory is applied on the solid solution in the form of clusters between the same tight stacking, stacking it fills the gap by connecting the atom, to establish a \. In this paper, BCC structure \, according to the component to determine the enthalpy of mixing between the cluster structure model in the specific component footprint, and ultimately get the specific composition ratio. In cluster model as a basis for Ti-Cr-V-based BCC solid solution hydrogen storage alloy composition of the structural analysis and design, to obtain a low-cost high-performance alloy composition. The main conclusions are as follows: (a) in the BCC lattice, stacking the tightness of clusters connected directly determine the number of atoms in x, which can be the position vector of the relationship between clusters represent. The results showed that clusters around a crystallographic group 1/2 lt; 3 3 1 gt;, 1/2 lt; 4 2 0 gt;, 1/2 lt; 4 2 2 gt;, 1/2 lt; 3 3 3 gt;, 1/2 lt; 5 1 1 gt; represents the position of the lattice of atoms in the amorphous described ball periodic pattern position relative to the approximate nearest neighbor clusters, the family of these crystals to a position corresponding to the position selected as the base vector vector set; basic position vector processing and composition of the entire mix of space form clusters. When the cluster stacking cycle by simple unicellular forms of expression throughout the space, based on the position vector set defines a single-cell basis vectors, and the unit cell size of the clusters directly reflects the accumulation of tightness. Clusters stacking tightness descending, the required number of atoms from the connection from x = 0 gradually increased, when x ≥ 3, the connection will be the same number of atoms corresponding to different clusters stacking configuration . Connection atoms, x = 0-6 corresponding to the configuration of the number of clusters stacking order of 1 (x = 0), 1 (x = 1), 1 (x = 2), 2 (x = 3), 2 ( x = 4), 5 (x = 5), 7 (x = 6). When connecting the atom more, can not be used to describe a simple cluster model, you need to structure is relatively complex to describe clusters stacking distribution of solute elements. (2) for the visual expression of solute atoms arranged between the relationship, we use the position vector of the basis of a set of clusters investigated clusters distributed around the neighborhood, and thus the introduction of super-clusters. When not account for cyclical constraints, according to the principle of closely spaced uniformly selected from the basic position vector centralized location with a super-cluster cluster structures, the use of exhaustive of all possible operational procedures, obtained 21 kinds can be extended to the space of a super-group clusters. Under mutual matching method can be applied to develop super-clusters cluster group to get space to get a series of two expansion program execution, three super-cluster configurations, and three super-clusters for statistical classification results show that clusters heap atomic pile connection with the highest probability of x = 1.5 and the ratio of x = 6. Through the results of all three levels of super-clusters level position over the respective partial statistics of clusters, the maximum probability obtained two super-clusters, the clusters corresponding to the positional relationship between the position vector of each of the shorter ( crystallographic group 1/2 lt; 3 3 1 gt;, 1/2 lt; 4 2 0 gt ;) and long position vector (orientation group 1/2 lt; 4 2 2 gt;, 1/2 lt; 5 1 1 gt ;) based. These topologies geometric computing require a combination of energy analysis to determine the distribution of solute atoms. (3) of the periodic structure model studies have shown that a 1:1 cluster structure model [Cluster] (connecting atom) 1 shows the highest degree of dispersion-atom, thereby forming the connecting atom alloying elements most effective way. Thus, we studied the Ti-Cr-V-based BCC solid solution hydrogen storage alloy composition design in order to obtain a low V content (connecting atom) high hydrogen storage properties of the alloy composition, lower alloy cost. In the Ti-Cr-V and Ti-Cr-V-Fe alloy system, the use of cluster structure models were designed [Ti1 (Cr8Ti6)] Vx and [Fe, (Ti8Cr6)] Vx alloy series, vacuum suction mold rapid cooling casting alloys were prepared, and its structural analysis and at different temperatures hydrogen absorption and desorption tests. The results showed that the content of low V Fe1Ti8Cr6V1BCC solution Ti7Cr8V1 and better performance hydrogen storage alloy, the maximum hydrogen capacity in 3.80wt% or more, and 333K, respectively in a 1.8wt% and 1.6wt% of the amount of hydrogen.
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