CN1439735A

CN1439735A - Manufacture of hydrogen storing alloy Mg2Ni

Info

Publication number: CN1439735A
Application number: CN 02145510
Authority: CN
Inventors: 夏天东; 裴新军; 刘天佐; 赵文军; 王晓军
Original assignee: GANSU POLYTECHNIC UNIV
Current assignee: GANSU POLYTECHNIC UNIV
Priority date: 2002-11-29
Filing date: 2002-11-29
Publication date: 2003-09-03
Anticipated expiration: 2022-11-29
Also published as: CN1165631C

Abstract

A process for preparing highrogen-bearing Mg2Ni alloy includes such steps as proportionally mixing Mg powder with Ni powder, preparing blank under 560-1000 MPa, heating in vacuum or inertial gas at a certain speed, holding temp for 0.5-1800 seconds to obtain mother alloy, and ball grinding for 2-50 hr.

Description

A kind of preparation Mg 2The method of Ni hydrogen-storage alloy

Affiliated field

The present invention relates to hydrogen storage preparation method.

Technical background

Magnesium (Mg) nickel (Ni) alloy is one of most important hydrogen-storage alloy, and its theoretical hydrogen storage amount is very high, and especially when its grain-size reached nanocrystalline, hydrogen storage amount significantly increased.Concentrating on both at home and abroad at present adds the prepared by mechanical alloy technology or utilizes the prepared by mechanical alloy technology to obtain separately nanocrystalline with traditional smelting technology, its weak point is: must heat during the preparation mother alloy, steaming pressure ratio owing to magnesium under the condition of high temperature is higher, it is comparatively serious to volatilize, in smelting process, must add the heavily refining process of magnesium, make process complications, and required time is longer, has increased preparation cost.Longer with the time of prepared by mechanical alloy magnesium-nickel alloy separately.In the process of mechanical alloying, only forming fragility phase Mg ₂The broken speed of crystal grain is just accelerated behind the Ni.In sum, the method for prior art for preparing Mg-Ni alloy exists composition to be difficult to control and power consumption, defective consuming time.

Summary of the invention

The present invention prepares Mg with self propagating high temperature is synthetic with mechanical ball milling ₂The method of Ni hydrogen-storage alloy, at first magnesium powder and nickel powder are mixed, the present invention presses Mg with magnesium powder and nickel powder: Ni=(1.8～2.2): 1 mixed is even, pressure with 560MPa～1000MPa is made blank, in vacuum or inert gas atmosphere, heat by rate of heating 0.33K/s≤V≤1.67K/s, be incubated at temperature 823K≤T≤1 033K then, 1800 seconds 〉=t of soaking time 〉=0.5 second makes Mg ₂The Ni mother alloy in the mechanical ball milling device, under protection of inert gas, adopts 50～500rpm rotating speed and 5～50 ratio of grinding media to material then, ball milling 2～50 hours, and acquisition at room temperature has the Mg of hydrogen storage property ₂The Ni powder body material.

Prepare Mg with self propagating high temperature is synthetic with mechanical ball milling according to above-described ₂The method of Ni hydrogen-storage alloy, its rate of heating V=0.33K/s T=1033K temperature insulation 1 second, adopts 50～500rpm rotating speed and 5～50 ratio of grinding media to material then under protection of inert gas, ball milling 2～50 hours, acquisition at room temperature has the Mg of hydrogen storage property ₂The Ni powder body material.

Prepare Mg with self propagating high temperature is synthetic with mechanical ball milling according to above-described ₂The method of Ni hydrogen-storage alloy, its rate of heating V=1.67K/s, T=823K temperature insulation 1800 seconds, 50～500rpm rotating speed and 5～50 ratio of grinding media to material were adopted in protection of inert gas down then, ball milling 2～50 hours, acquisition at room temperature has the Mg of hydrogen storage property ₂The Ni powder body material.

Specific implementation

The present invention prepares Mg with self propagating high temperature is synthetic with mechanical ball milling ₂The Ni hydrogen-storage alloy; at first take by weighing a certain amount of Mg powder and Ni powder; press Mg: Ni=(1.8～2.2): 1 mixed is even; these two kinds of powder mixes are placed in the ball grinder; the abrading-ball that in ball grinder, adds some amount; ball grinder is loaded on the ball mill Mg; the Ni powder is further pulverized; mix; take by weighing the Mg that mixes; the Ni mixture; apply 560MPa≤P≤1000MPa pressure and be pressed into blank; blank is placed the Reaktionsofen that is filled with inert protective gas; rare gas element herein can adopt argon gas; heat by rate of heating 0.33K/s≤V≤1.67K/s; be incubated at temperature 823K≤T≤1033K then, 1800 seconds 〉=t of soaking time 〉=0.5 second is then in the mechanical ball milling device; under protection of inert gas; adopt 50～500rpm rotating speed and 5～50 ratio of grinding media to material, mother alloy was ground 2～50 hours the Mg of acquisition ₂The Ni powder body material has hydrogen storage property in room temperature.

At charge/discharge current density 50mAhg ^-1, under the duration of charging 9h, stopping potential 0.6V condition, will adopt the Mg of the synthetic and mechanical ball milling preparation of self propagating high temperature of the present invention ₂The powder of Ni hydrogen-storage alloy mixes with the Ni powder, be pressed into and make electrode on the porous nickel mesh, electrode is soaked 12h in the 6MKOH alkaline solution, measure chemical property under the normal temperature and pressure in filling the H type three-electrode system of 6MKOH alkaline solution, the highest discharge capacity of circulation reaches 251mAhg for the first time ^-1Through six charge/discharge cycle, loading capacity decays to 38mAhg ^-1

Claims

1, synthetic and mechanical ball milling prepares Mg with self propagating high temperature ₂The method of Ni hydrogen-storage alloy, at first magnesium powder and nickel powder are mixed, feature of the present invention be with magnesium powder and nickel powder by Mg: Ni=(1.8～2.2): 1 mixed is even, pressure with 560MPa～1000MPa is made blank, in vacuum or inert gas atmosphere, heat by rate of heating 0.33K/s≤V≤1.67K/s, be incubated at temperature 823K≤T≤1033K then, 1800 seconds 〉=t of soaking time 〉=0.5 second makes Mg ₂The Ni mother alloy in the mechanical ball milling device, under protection of inert gas, adopts 50～500rpm rotating speed and 5～50 ratio of grinding media to material then, ball milling 2～50 hours, and acquisition at room temperature has the Mg of hydrogen storage property ₂The Ni powder body material.

It is 2, according to claim 1 that synthetic and mechanical ball milling prepares Mg with self propagating high temperature ₂The method of Ni hydrogen-storage alloy; it is characterized in that rate of heating V=0.33K/s,, under protection of inert gas, adopt 50～500rpm rotating speed and 5～50 ratio of grinding media to material then T=1033K temperature insulation 1 second; ball milling 2～50 hours, acquisition at room temperature has the Mg of hydrogen storage property ₂The Ni powder body material.

It is 3, according to claim 1 that synthetic and mechanical ball milling prepares Mg with self propagating high temperature ₂The method of Ni hydrogen-storage alloy; it is characterized in that rate of heating V=1.67K/s,, under protection of inert gas, adopt 50～500rpm rotating speed and 5～50 ratio of grinding media to material then T=823K temperature insulation 1800 seconds; ball milling 2～50 hours, acquisition at room temperature has the Mg of hydrogen storage property ₂The Ni powder body material.