A kind of nanostructured block magnesium material and preparation method
Technical field
The present invention relates to a kind of magnesium material, more particularly to a kind of nanostructured block magnesium material and preparation method.
Background technology
The present invention relates to a kind of block magnesium material with nanostructured, the material has consistency high, high excellent of hardness
Point, is a kind of preferable high-strength light structural material, can also be used as a kind of hydrogen storage material of high power capacity.
With the rapid development of economy, people are continuously increased for the demand of the energy.However, the change that people rely on for a long time
Stone energy reserve just constantly declines, according to British Petroleum Company(BP)Research prediction, according to current exploitation rate, coal stone oil is natural
Gas will all run out in 120 years.Meanwhile, largely using fossil fuel, severe contamination environment, acid rain, Melting Glacierss, high temperature mist
The phenomenons such as haze, EI Nino emerge in an endless stream, and just drastically influence the Health and Living of the mankind.Based on this, development reserves are enriched, ring
The friendly new energy in border is extremely urgent.In recent years, hydrogen because with combustion heat value is high, pollution-free, density light and protium regardless of
The characteristics of national boundaries are widely distributed and by the common concern of people.But widely used to hydrogen energy source, safe and efficient storage fortune
Defeated is key link.In recent years, researcher both domestic and external always for seek the breakthrough of this technology and effort.
Alloy hydrogen storage is considered as always most promising hydrogen storage mode, developed at present Ti systems, Rare Earth, V systems and
The hydrogen bearing alloy system such as Mg systems.Wherein, pure magnesium because its theoretical hydrogen storage capability it is big(7.6wt%), cheap, aboundresources, density
Small the features such as, and enjoy the favor of researcher.But the suction hydrogen desorption kineticses poor-performing of pure magnesium, inhales the higher grade of hydrogen discharging temperature and lacks
Point hinders its practical application.Instantly mainly magnesium-base hydrogen storage material is improved from nanosizing and addition two dimensions of catalyst
Energy.But nanosizing also reduces material heat transmitting while hydrogen storage property is improved, and adds the heat of hydrogenation/dehydrogenation reaction
Diffusion time, nano material is due to high surface-active, easily oxidation even spontaneous combustion, this accumulating bar to hydrogen storage material
Part brings challenge.
Therefore, those skilled in the art is directed to developing a kind of hydrogen storage property and all good new magnesium material of hot property.
The content of the invention
In view of the drawbacks described above of prior art, the technical problems to be solved by the invention are to provide one kind and have a nanometer material concurrently
Expect excellent hydrogen storage property and block materials excellent heat transfer, the nanostructured block hydrogen storage material of stability, and provide one
The preparation method of nanostructured block materials is planted, it is big to be carried out in terms of the scale transport of hydrogen and fuel cell
Scale is used.
To achieve the above object, the invention provides a kind of block magnesium material, block magnesium material includes the magnesium of nanostructured.
This block magnesium material has the dual property advantage of nano material and common block materials, and hydrogen power is put in existing advantageous suction
Performance is learned, there is higher block density and the thermal conductivity thermal efficiency again, consistency is high, hardness is high.
Further, block magnesium material includes at least one magnesium-yttrium-transition metal, and magnesium-yttrium-transition metal is in block magnesium material
Nanostructured, the ratio that magnesium-yttrium-transition metal weight accounts for block magnesium material weight is less than 20%.The preferred iron of magnesium-yttrium-transition metal, nickel etc. are often
See metal, these metal sources are extensive, cost is relatively low, and can be easily made nano powder.This block magnesium material is used as hydrogen storage material
When, wherein magnesium-yttrium-transition metal plays catalytic action, promotes the reaction bonded of magnesium and hydrogen.
The invention also discloses the preparation method of above-mentioned block magnesium material, including two key steps:
(1)Metal derby forms metal nano powder through fusing, evaporation, cooling;
(2)Metal nano powder is pressed into block materials through high pressure torsion, and high pressure refers to 0.3-3.0GPa pressure herein.
Further, wherein the preparation of metal nano powder includes following detailed step:
(a)DC arc plasma equipment is vacuumized, and is filled with the mixed gas of argon gas and hydrogen;
(b)Metal derby is anode, and tungsten bar is negative electrode;The starting the arc makes metal derby melt and evaporate;
(c)The metal vapors cooling that evaporation is formed, obtains active metal powder;
(d)The passivated processing of active metal powder, obtains metal nano powder.
Further, DC arc plasma equipment is evacuated to less than 5 × 10-2Pa, is re-filled with argon gas and hydrogen
The air pressure of mixed gas, wherein argon gas is 0.45-0.7atm, and the air pressure of hydrogen is 0.1atm.
Further, after the starting the arc starts, gas is flushed with hydrogen to 1atm, current control is in 120-150A.
Further, metal vapors is cooled down by water cooling, cooling water temperature is controlled in room temperature, the water of cooling water
Press as 2-3MPa.The cooling water of higher hydraulic pressure, can quickly take away the heat of reaction chamber wall, metal evaporation is in reative cell
Wall, rapid cooling makes crystal be difficult growth, obtains active metal powder, and this metal powder crystal is tiny and active big, it is necessary to do blunt
Change is handled.
Further, obtain after active metal powder, stand 2h, DC arc plasma equipment is vacuumized, is filled with
The mixed gas of argon gas and air, wherein ar pressure are 0.6-0.7atm, and air pressure is 0.05atm, afterwards every 0.5h,
0.05atm air is filled with, until the total gas pressure of argon gas and air reaches 1atm, is further continued for keeping more than passivating process 10h, collects blunt
Metal dust after change, is made metal nano powder.Atm refers to standard atmospheric pressure, 1atm=101325Pa ≈ 1.01MPa herein.
Further, magnesium nano powder is pressed into pure magnesium block materials using high pressure torsion equipment, comprised the following steps:Will
Magnesium nano powder is placed in mould, and mould installion is on equipment pressure head, at room temperature, applies 300MPa pressure at right angle, is kept
5min or so, while reversing 1-5 circles, is made pure MAG block body magnesium material.
Or, metal nano powder is pressed into block materials containing magnesium-yttrium-transition metal using high pressure torsion equipment, including it is as follows
Step:Magnesium nano powder and at least one magnesium-yttrium-transition metal nano powder are well mixed, hybrid metal nano powder is obtained, then will mixing
Metal nano powder is placed in mould, and mould installion is on high pressure torsion equipment pressure head, at selected temperature, applies 0.3-
1.2GPa pressure at right angle, keeps 5min or so, while reversing 0.5-5 circles, the block magnesium material containing magnesium-yttrium-transition metal is made;Choosing
Fixed temperature refers to room temperature to any temperature between 250 DEG C.Room temperature refers to 25 DEG C, but also may be used between 20-30 DEG C.
In the better embodiment of the present invention, pure magnesium nano powder is made in MAG block, then be pressed into through high pressure torsion equipment
Pure MAG block body magnesium material.
In another better embodiment of the present invention, magnesium nano powder and iron nano powder is respectively prepared in MAG block and iron block,
After both are well mixed by a certain percentage, iron content block magnesium material is pressed into through high pressure torsion equipment.
In the another better embodiment of the present invention, magnesium nano powder and nickel nano powder is respectively prepared in MAG block and nickel block,
After both are well mixed by a certain percentage, nickeliferous block magnesium material is pressed into through high pressure torsion equipment.
The technique effect of the present invention:
The block magnesium material prepared by metal nano powder by high pressure torsion has nano material and common block materials
Double dominant, existing advantageous suction hydrogen desorption kineticses performance, has higher block density and the thermal conductivity thermal efficiency, it is easy to preserve again
And transport, a kind of hydrogen storage material of high power capacity can be used as;The material has the advantages that consistency height, hardness are high simultaneously, is also
A kind of preferable high-strength light structural material.
The technique effect of the design of the present invention, concrete structure and generation is described further below with reference to accompanying drawing, with
It is fully understood from the purpose of the present invention, feature and effect.
Brief description of the drawings
Fig. 1 is the part-structure schematic diagram that the present invention prepares the high pressure torsion equipment used in block magnesium material;
Fig. 2 is the microscopic appearance picture of the magnesium nano powder of arc evaporation preparation in embodiment 1, and picture is by model
Obtained captured by QUANTA FEG250 SEM;
Fig. 3 is the suction hydrogen power that iron content block magnesium material made from embodiment 2 depresses 300 DEG C of temperature in initial 3MPa hydrogen
Curve is learned, is tested in P-C-T instruments;
Fig. 4 is that hydrogen PCT is put in suction of the nickeliferous block magnesium material respectively at 300 DEG C, 350 DEG C, 400 DEG C made from embodiment 3
Curve map, test is carried out in P-C-T testers;
Fig. 5 is DSC/TGA curve of the nickeliferous block magnesium material made from embodiment 3 after 400 DEG C, 4MPa hydrogen pressure suction hydrogen,
Test is carried out in resistance to DSC/TGA instruments of speeding;Test condition:Argon gas atmosphere, flow velocity 30ml/min;10 DEG C/min of heating rate;
Temperature range is 100-510 DEG C.
Embodiment
During shown in Fig. 1 is the embodiment of the present invention, metal nano powder is pressed into the high pressure torsion used in block materials
The part-structure schematic diagram of device.The part-structure of equipment, including upper mould 1, lower mould 2, seaming chuck 3, push-down head 4.Upper mould 1 is convex
Mould, lower mould 2 is cavity plate, and upper mould 1 and lower mould 2 can be fitted close.It is as follows using process:Upper mould 1 and lower mould 2 are separated, upper mould
The bottom of the seaming chuck 3 of equipment is fixedly mounted on, lower mould 2 is fixedly mounted on the top of the push-down head 4 of equipment, and metal nano powder is put
Put between upper mould 1 and lower mould 2, seaming chuck 3 and push-down head 4 are close to each other, mould 1 and lower mould 2 is combined closely.Pressure head applies
While pressure, seaming chuck 3 and push-down head 4 are for the relative rotation, and metal nano powder is pressed into block materials.If necessary, pressure head
It can heat, and sample is brought by heat by mould.
The compressing block materials of high pressure torsion are different from common compressing block materials.In the present invention, compacting
While rotated, collective effect of the material through very high pressure and shearing force obtains excellent performance, and pressure makes nano-powder
Block is combined into, but shearing force can control crystal growth, it is ensured that and the metal of bulk inner continues to keep nanostructured, and this is this
The key point of invention.
Embodiment 1:
The high purity magnesium that this experiment is used is commercially available, and MAG block is cut to length by purity more than 99.9% with abrasive wheel cutting machine
4cm × wide 4cm × high 2cm regular block, and with the oxide layer on sand mill removing MAG block surface, as anode.Nanostructured
The preparation of block magnesium material is broadly divided into two steps:(1)Direct current arc method prepares magnesium nano powder;(2)It is prepared by high pressure and torsion
Block magnesium material.
Step(1):A kind of method for preparing magnesium nano powder:Using high purity magnesium metal blocks as anode, tungsten bar is used as negative electrode
It is placed in DC arc plasma equipment.When equipment is evacuated to 5 × 10-2After Pa, argon gas is filled with to 0.7atm, is re-filled with
0.1atm hydrogen.Logical cooling water, water temperature is controlled in room temperature, and hydraulic pressure is 2.5MPa.Plasma-arc is produced with hf arc starter,
In the presence of high-temperature electric arc, anode metal MAG block is melted and evaporated rapidly, and metal vapors is mutually collided with argon gas, hydrogen molecule,
Finally it is deposited on the inwall of reative cell, striking current is 120A, after evaporation 8min, extinguishes electric arc, cooling.Stationary equipment 2h is left
The right side, 20Pa is evacuated to by equipment, then carries out in-situ passivation processing to powder, i.e., be filled with first 0.6atm argon gas with
0.05atm air, is hereafter filled with 0.05atm air until the big 1atm of total gas pressure every 0.5h.10h is passivated again, collects interior
Wall powder, is made nano powder.
Step(2):A kind of method that high pressure torsion prepares block magnesium material:By mould installion in high pressure torsion equipment pressure head
On, then magnesium nano powder is placed between the upper mould of mould and lower mould.At room temperature, apply 300MPa pressure at right angle, keep
3min, encloses while reversing 1, obtains pure MAG block body magnesium material.Fig. 2 is magnesium nano powder microscopic appearance figure, shows of magnesium nano powder
Particle size is 80-560nm.
Embodiment 2:
High purity iron, high purity magnesium are commercially available in this experiment, and purity is similar to Example 1 up to more than 99.9%, uses sand
MAG block and iron block are cut to long 4cm × wide 4cm × high 2cm regular block by wheel cutting machine, and remove block surface with sand mill
Oxide layer, as anode.Experiment is main to include three steps:(1)The preparation of magnesium nano powder;(2)The preparation of iron nano powder;
(3)The preparation of iron content block magnesium material.Preparing for magnesium nano powder is substantially the same manner as Example 1, and concrete operations may be referred to implement
The relevant portion of example 1, below by main illustrative step step(2)And step(3).
Step(2):A kind of preparation method of iron nano powder:Using high purity iron metal blocks as anode, tungsten bar is used as negative electrode
It is placed in DC arc plasma equipment.When equipment is evacuated to 5 × 10-2After Pa, argon gas is filled with to 0.45atm, is re-filled with
0.1atm hydrogen.Logical cooling water, water temperature is controlled in room temperature, and hydraulic pressure is 2.4MPa.Plasma-arc is produced with hf arc starter,
In the presence of high-temperature electric arc, anode metal iron block is melted and evaporated rapidly, and metal vapors is mutually collided with gas molecule, is finally sunk
Product is on the inwall of reative cell;Striking current is set as being filled with hydrogen after 150A, the starting the arc to 1atm, evaporates after 10min, extinguishes electricity
Arc, cooling.Stationary equipment 2h or so, 15Pa is evacuated to by equipment, is then carried out in-situ passivation processing to powder, i.e., is filled first
Enter 0.7atm air of the argon gas with 0.05atm, be hereafter filled with 0.05atm air every 0.5h until total gas pressure reaches 1atm.
12h is passivated again, inwall powder is collected, and iron nano powder is made.
Step(3):A kind of method that high pressure torsion prepares iron content block magnesium material:By upper die and lower die, height is respectively arranged in
Press torsion equipment seaming chuck and push-down head.By magnesium nano powder and iron nano powder with 49:1 mass ratio is uniformly mixed in mortar,
Mixed powder is placed in mould again.At room temperature, apply 300MPa pressure at right angle, keep 4min, enclose, obtain while reversing 2
To iron content block magnesium material, wherein iron and magnesium can keep nanostructured.
Fig. 3 is the Dynamic isotherms of hydrogen absorption figure that iron content block magnesium material is depressed in 300 DEG C, 4MPa hydrogen, and it shows iron content magnesium
Nanometer blocks have adsorbed the 65% of total amount in 200s, and this performance is better than the 55% of pure MAG block body magnesium material.Iron is in magnesium and the knot of hydrogen
Close in reaction, play a part of catalyst.
Embodiment 3
High purity nickel, high purity magnesium are commercially available in this experiment, and purity is similar to Example 1 up to more than 99.9%, uses sand
MAG block and nickel block are cut to the regular blocks of long 4cm × wide 4cm × high 2cm by wheel cutting machine, and remove block surface with sand mill
Oxide layer, as anode.Experiment is main to include three steps:(1)The preparation of magnesium nano powder,(2)The preparation of nickel nano powder;(3)
The preparation of nickeliferous block magnesium material.Preparing for magnesium nano powder is substantially the same manner as Example 1, and concrete operations may be referred to embodiment 1
Relevant portion, below by main illustrative step(2)And step(3).
Step(2):A kind of preparation method of nickel nano powder:Using high purity nickel metal blocks as anode, tungsten bar is used as negative electrode
It is placed in DC arc plasma equipment.It is 5 × 10 when equipment is extracted into vacuum-2After Pa, argon gas is filled with to 0.5atm, then fill
Enter 0.1atm hydrogen.Logical cooling water, water temperature is controlled in room temperature, and hydraulic pressure is 2.6MPa.Plasma-arc is produced with hf arc starter,
In the presence of high-temperature electric arc, anode metal block is melted and evaporated rapidly, and metal vapors is mutually collided with gas molecule, is finally sunk
Product is on the inwall of reative cell;Striking current is set as being filled with hydrogen after 140A, the starting the arc to 1atm, evaporates after 15min, extinguishes electricity
Arc, cooling.Stationary equipment 2h or so, 10Pa is evacuated to by equipment, is then carried out in-situ passivation processing to powder, i.e., is filled first
Enter 0.6atm air of the argon gas with 0.05atm, be hereafter filled with 0.05atm air until the big 1atm of total gas pressure every 0.5h.
12h is passivated again, inwall powder is collected, and nickel nano powder is made.
Step(3):A kind of method that high pressure torsion prepares nickeliferous block magnesium material:By upper die and lower die, it is respectively arranged in
High pressure torsion equipment seaming chuck and push-down head.By magnesium nano powder with nickel nano powder, with 24:1 mass ratio is uniformly mixed in mortar
Close, then mixed powder is placed in mould.At room temperature, apply 500MPa pressure at right angle, keep 5min, enclosed while reversing 3,
Nickeliferous block magnesium material is obtained, wherein nickel and magnesium can keep nanostructured.
Fig. 4 shows the PCT curves of nickeliferous block magnesium material at different temperatures, and it almost puts completely at relatively low 300 DEG C
Hydrogen, but be then impossible for pure magnesium sample at 300 DEG C.Fig. 5 TGA-DSC curves display starting purer magnesium of hydrogen discharging temperature
Block materials are low 20 DEG C.
Preferred embodiment of the invention described in detail above.It should be appreciated that one of ordinary skill in the art without
Need creative work just can make many modifications and variations according to the design of the present invention.Therefore, all technologies in the art
Personnel are available by logical analysis, reasoning, or a limited experiment on the basis of existing technology under this invention's idea
Technical scheme, all should be in the protection domain being defined in the patent claims.