| In this thesis, the research and development of hydrogen storage alloys with BCC vanadium-based solid solution were reviewed first. On this basis, Ti-Cr-V based alloys with high hydrogen content were chosen as the objects of this study. By means of XRD, SEM, EDS analysis and hydriding/dehydriding measurements, the influence of V content on the microstructures and hydrogen storage characteristics of Ti-Cr-V ternary alloys has been investigated. Then, the effects of multi-component alloying and the alloy preparation methods (including heat-treatment and rapidly quenching) on the microstructures and hydrogen storage properties of the alloys have been studied systemically. The purpose of such investigation is to improve the overall properties of Ti-Cr-V based alloys.The study on the microstructures and hydrogen storage properties of (Ti-Cr)ioo-xVx (x=1060; Ti/Cr= 0.7-0.8) alloys show that the alloy with V content of x≤30 consists of a V-based solid solution main phase with BCC structure and an a-Ti secondary phase. As x= 35-55, the alloys have only a single BCC phase. As x= 60, a C15 type Laves secondary phase appears in the alloy. It is found that with the increase of V content in the alloys, the activation behavior descends. The hydrogen absorption capacity at room temperature and the effective hydrogen desorption capacity at 90℃ increases first and then decreases, and reaches a maximum value as x=55. The hysteresis of P-C-T curves for these alloys is great. The alloy with x-55 has a good overall property, such as the hydrogen absorption capacity of 396 ml/g at room temperature and the effective desorption capacity of 216 ml/g at 90 ℃On the basis of the above work on the ternary alloys, the effects of the partial substitution of Ti-Cr by Zr on the microstructures and hydrogen storage characteristics of (Ti-Cr)45.xV55Zrx (x= 1, 3, 5, 7; Ti/Cr = 0.7-0.8) alloys have been investigated. The results show that the alloy with x= 1 consists of a V-based solid solution main phase and an a-Zr secondary phase. As x= 3-7, the alloys consist of a V-based solid solution main phase and an a-ZrCr2 secondary phase. It is found that with the increase of Zr content in the alloys, the activation behavior is improved; the hydrogen absorption capacity at 20℃ and the effective hydrogen desorption capacity at 80℃ all increase first and then decrease, while the maximum values are obtained at x=5. The hysteresis of the P-C isotherm decreases and its slope increases. Among the alloys studied, (Ti-Cr)40V55Zr5 alloy has a good overall property, such as the activation behavior of 2 cycles, the hydrogen absorption capacity of 403 ml/g at room temperature and the effective desorption capacity of 230 ml/g at 80 ℃On the basis of the above work on the quadruple alloys, the effects of heat treatment (1473Kx2h or 6 h) and rapidly quenching on the microstructures and hydrogen storage characteristics of Ti-Cr-V-Zr alloys have been investigated systemically. It is found that the alloys after heat treatment consist of a V-based solid solution main phase, an α-ZrCr2secondary phase and some third phase. After heat treatment, the activation behavior is improved, the hysteresis and the slope of the P-C-T curves all decrease. Among the alloys studied, (Ti-Cr)40V55Zr5 alloy after the heat treatment of 1473Kx2h has the best overall properties, its hydrogen absorption capacity is 401 ml/g at room temperature and its effective desorption capacity is 240 ml/g at 80℃. The study on the rapidly quenched (Ti-Cr)40V55Zr5 alloy shows that the ZrCr2 secondary phase in the rapidly quenched (Ti-Cr)40V55Zr5 alloy is almost disappeared, and the BCC main phase is enhanced and its cell volume decreases. The rapidly quenched alloy has a worse kinetic properties and the effective desorption capacity of 196 ml/g (at 80℃).To judge the feasibility of V substituted by ferrovanadium, the microstructures and hydrogen storage properties of TinCr2V55-xZr5Fex (x= 11, 12, 14, 16) alloys have been investigated. The results show that all of the alloys consist of a main phase o...
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