Preparation method of rare-earth magnesium nickel based hydrogen storage alloy

Abstract

The invention discloses a preparation method of a rare-earth magnesium nickel based hydrogen storage alloy. The preparation method comprises the following steps: adopting a round or square graphite electrolytic cell, putting a carrying crucible at the bottom of the electrolytic cell, and presetting a certain amount of addition element metal blocks into the carrying crucible; taking fluoride molten salts including REF3-LiF-MgF2-BaF2 and the like as an electrolytic medium and a mixture of RE2O3 and MgO as a raw material, electrochemically precipitating out RE and Mg together at a cathode to obtain an RE-Mg alloy which sinks into the carrying crucible and alloyed with the metal blocks preset in the crucible so as to obtain the rare-earth magnesium nickel based hydrogen storage alloy. The preparation method can be used for effectively solving the problem of volatilization and oxidation of magnesium during smelting of the rare-earth magnesium nickel based hydrogen storage alloy, and is safe in production process, short in flow and low in cost. The rare-earth magnesium nickel based hydrogen storage alloy prepared by the method can be directly crushed mechanically or subjected to hydrogen crushing to obtain rare-earth magnesium nickel based hydrogen storage alloy powder, or can be used as a master alloy which is subjected to pouring or rapid quenching after a certain raw material is added, and then is crushed mechanically or subjected to hydrogen crushing to obtain the rare-earth magnesium nickel based hydrogen storage alloy powder.

Description

technical field [0001] The invention relates to a preparation method of a rare-earth magnesium-nickel-based hydrogen storage alloy. Background technique [0002] RE-Mg-Ni series hydrogen storage alloy is a new generation of high-performance rare earth hydrogen storage material developed in recent years. Its hydrogen storage weight hydrogen storage density is between 1.4-6% according to its composition, and its comprehensive performance is superior. There are many preparation techniques for RE-Mg-Ni alloys. On the whole, there are mainly high-temperature diffusion sintering techniques, such as CN1271025A, CN1296083A, CN1598018A, CN1900337A; vacuum induction melting techniques, such as CN1397658A, CN102191416A, CN102277508A, CN102286684A; Such as CN1316537A, CN1644737A; vacuum rapid quenching technology, such as CN101624660, CN101626076A; laser sintering, such as CN101029358A, etc.; the patent basically involves inert gas or H 2 Protection during alloying, even positive press...

AI Technical Summary

Problems solved by technology

[0003] Because the melting point and boiling point of magnesium, rare earth, and nickel are very different, the high activity and volatility of magnesium make it very difficult to control its content. Mg volatilization is very easy to occur in the process of smelting and heat treatment. On the one hand, the Mg content in the alloy Deviating from the design value, on the other hand, the production is not safe

In addition, composition segregation and uneven structure are easy to occur during the solidification process of the alloy. The long annealing process cycle is easy to cause the alloy to be oxidized, which affects the performance of the alloy, making it difficult to control the quality of the alloy product, and even has safety problems.