Preparation method of Mg-Ni series hydrogen storage alloy

Abstract

The invention relates to a preparation method of Mg-Ni series hydrogen storage alloy, which belongs to the preparation of hydrogen storage alloy in metallic functional materials. The method comprises the following steps: by adopting spark plasma sintering technology, Mg powders, Ni powders and NdNi alloyed powders are configured according to the mixture ratio of Mg2-xNdxNi, wherein x is more than or equal to 0.1 and less then or equal to 0.5; the Mg powders, the Ni powders and the NdNi alloyed powders are evenly mixed by a planetary ball mill, and then the powders are put into an SPS special die for compression; spark plasma sintering is carried out to the die filled with original powders under the vacuum atmosphere; while in sintering, the heating speed is 50-150 DEG C, the sintering temperature is 400-500 DEG C, the sintering pressure is 10-30 MPa, and the holding time is 5-10min. The invention solves the problem that the preparation of Mg-Ni series hydrogen storage alloy is difficult and has simple preparation process, time saving, good controllability and low cost; and the prepared hydrogen storage alloy is in multiphase structure and has favorable activation property, good absorption and desorption hydrogen kinetics performance, favorable PCT platform property, high hydrogen desorption and good hydrogen absorption and desorption reversibility.

Description

technical field [0001] The invention belongs to the preparation of hydrogen storage alloy in metal functional materials, in particular to a discharge plasma sintering technology. Background technique [0002] With the development of human beings, the energy problem has become a serious crisis before us. Fossil fuels will eventually be exhausted, and in the process of use, they will also cause a lot of environmental pollution problems, seriously affecting human survival. Therefore, the development of new environmentally friendly energy sources is imminent, and countries have also taken effective measures to carry out this work. Among many new energy sources, hydrogen energy is favored by people because it is an environmentally friendly energy source. Hydrogen is a fuel with a high calorific value. Combustion product of hydrogen-oxygen combination is the cleanest substance - water, without any pollution. The most promising fuel cells in the future are also mainly based on h...

AI Technical Summary

Problems solved by technology

For Mg-Ni-based alloys, due to the large difference in melting point and volatility of Mg and Ni, when Mg-Ni alloys are prepared by traditional smelting methods, it is necessary to continuously add Mg for re-smelting. When the master alloy is prepared, During the rapid quenching process, the master alloy needs to be remelted again, and Mg will be further volatilized. The traditional smelting and traditional rapid quenching process make it difficult to control the composition of the Mg-Ni-based hydrogen storage material; in comparison, the mechanical alloying method can overcome the Magnesium metal has the disadvantages of low melting point and high vapor pressure, but the preparation of magnesium-based hydrogen storage alloy by mechanical alloying requires a long ball milling time, ranging from 3 days to 6-8 days at most, the preparation efficiency is low, and it is easy to introduce impurity pollution The hydrogenation combustion method is a kind of solid-state combustion reaction, which usually synthesizes Mg-Ni-based alloys by solid-state combustion in an argon or hydrogen atmosphere. It has the advantages of energy saving and simple equipment, but its main disadvantage is poor repeatability; - Ni-based alloys are not easy to bring in impurities. When the synthesis temperature is not high, the saturated vapor pressure of magnesium is small, and it is easy to control the composition ratio and content of the alloy, but the disadvantage is that the sintering time is long and it is difficult to produce in large quantities.

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