REMg3 type hydrogen storage alloy and its preparation method

Abstract

A hydrogen bearing REMg3 alloy has a molecular formula: RE1.2-xMg3Niy, where RE is rare-earth mixture, x=0-0.4 and y=0-1. Its preparing process includes proportionally loading RE, Mg and Ni in crucible of induction furnace, vacuumizing, filling protective gas, smelting and cooling.

Description

technical field [0001] The invention relates to the technical field of hydrogen storage materials, in particular to a REMg 3 Type hydrogen storage alloy and its preparation method. Background technique [0002] The hydrogen storage alloys currently used and researched can be divided into AB according to the composition and structure 5 Type rare earth series, AB 2 Type Laves phase, V-based solid solution type, AB type, A 2 B and AB 3 There are six types of alloys, in which A is a hydrogen-absorbing component, and B is a catalytic pair component for hydrogen absorption. Table 1-1 lists the performance parameters of several main hydrogen storage alloys (metals). [0003] Types of Hydride Hydrogen storage capacity (wt.%) Equilibrium pressure (temperature) (10 5 Pa, (K)) Enthalpy (kJ mol -1 ) LaNi 5 ZrMn 2 ZrV 2 V TiFe Mg Mg 2 Ni T...

AI Technical Summary

Problems solved by technology

[0018] (1) Alloy Mg 75 Ni 20 Mmm 5 The dehydrogenation pressure platform is too low, it is not easy to activate, and it is difficult to promote to practical application;

[0019] (2) Alloy Mm 1-y m y (NiCoN) x Contains expensive metal elements such as Mo, Co, Pt, Hf, Ta, Ge, etc., and the cost is high;

[0020] (3) Alloy Mm 1-y m y (NiCoN) x Contains V, Zr, Pd, Cd, In and other metal elements that will cause serious environmental pollution, which will pollute the environment;

[0021] (4) Alloy A 1-y B y C x Does not contain Ni element, so that its hydrogen storage performance is poor;

[0022] (5) The existing production process is prepared by melting in a vacuum magnetic levitation furnace or an electric arc furnace, which is difficult to operate and difficult to carry out mass production;

[0023] (6)Ml 1-x Mg x Ni y (0.02≤x≤0.8, 2≤y≤4) alloy structure and phase abundance are difficult to control, the preparation process includes smelting, homogenization annealing, mechanical alloying and other processes, the preparation process is complicated, and the nickel content is high, and the cost is high