A kind of room temperature height forming magnesium alloy plate and preparation method thereof
Technical field
The present invention relates to a kind of room temperature height forming Mg-Zn-Er alloys and preparation method thereof, and in particular to passes through certain conjunction
The preparation such as golden ingredient, smelting technology and rolling condition;The alloy has good formability at room temperature, is that one kind has potential answer
With the magnesium alloy materials of the high forming of prospect, belong to sheet alloy technical field.
Background technique
In recent years, environmental protection is increasingly subject to global attention, improves the service efficiency of the energy, reduces the discharge of pollutant,
It has become a top priority.The characteristics of magnesium metal is with reserves abundant and lightweight causes the extensive attention of domestic and international experts and scholars.
Magnesium alloy has high specific strength, high specific stiffness, the excellent performances such as good damping property and machinability, in automobile component, portable
There are potential application prospects and development space in formula electronic device and Biodegradable implant, be known as " 21 century green
Engineering material ".The usage amount of magnesium alloy is with annual 20% or more speed increase.However, magnesium has close-packed hexagonal structure, room temperature
Under plastic deformation ability it is bad, and coarse grains and surface oxidation easily occur under high temperature, cause forming capacity poor, this at
To restrict magnesium alloy materials further widely applied important factor in order.Therefore, at present in military project, civilian and medical field,
The forming capacity for improving magnesium alloy becomes primary goal.
The magnesium-alloy material of current research is based on casting, and especially die casting is in the majority, and plastic process product is comparatively
It is less, but the mechanical property of casting is poor, is also easy to produce defect, and wrought magnesium alloy fine microstructures are uniform, comprehensive mechanical performance is good.
Studies have shown that reduction basal plane texture can significantly improve the plastic forming ability of magnesium alloy, therefore various technologies are widely deployed simultaneously
It applies.The current research to magnesium alloy plastic forming technology both at home and abroad, is concentrated mainly on forging, extruding, rolling etc., due to
Magnesium alloy forged difficulty is larger, complicated for operation and be not easy to control to temperature and strain hardening and strain-rate sensitivity, thus this method apply compared with
Few, there is extrusion effect for other pressure processing methods, intensity highest, moulding reduces the material of extruding, from aobvious
From micro-assembly robot, extruding metaplasia is the fiercest, and deformation texture is the strongest.
A kind of basic forming means one of of the rolling technique as plastic deformation, are a kind of widely used processing technologies.
A large number of studies show that since rolling magnesium alloy is dispersed with very strong basal plane texture on rolling plane, so that magnesium alloy plate edge
Deformation in thickness it is difficult, strong basal plane texture has seriously affected the secondary forming performance of magnesium alloy, has constrained magnesium alloy
Application.The basal plane texture that decrease rolls rear plate can reduce anisotropy significantly, improve the forming capacity of material.Therefore,
Need to develop novel rolling mill practice.When rolling deformation can according to the actual temperature of plate, be divided into hot rolling, warm-rolling and
Cold rolling three types: cold rolling is the rolling that occurs below of recrystallization temperature in alloy, and alloy only occurs to reply without again
Crystallization.Therefore, work hardening rate is larger, and the rolling of alloy is made to be difficult to go on.Warm-rolling is the recrystallization more than recovery temperature
The operation of rolling that temperature occurs below, alloy processing hardening tend to larger.For the feature that magnesium alloy plastic deformation ability is poor,
Hot rolling is mainly used in practical application.Annealing can make magnesium alloy that Recovery and recrystallization occur, and weaken the basal plane texture of plate.
Currently, more mature magnesium alloy plate production technology mainly has ingot casting-rolling, casting and roll process and extruding-rolling.
Ingot casting-rolling is the production method for being earliest also Strip most widely used so far.Using the current China of the method
Most wide magnesium alloy cut deal and size up to 2600mm can be produced and be up to δ 1.0~2.5 ×~1500 ×~3000mm magnesium
Latten.Casting and roll process is in the 1980's since the mature of aluminium rolling casting technology just starts starting research, is by magnesium alloy melt
Direct Rolling eliminates the intermediate link that casting rolls again, enormously simplifies production technology at magnesium alloy slab.But casting
The magnesium alloy plate surface defect and internal segregation of method production are serious, and production wide plate is difficult, and mechanical property is bad.It squeezes
Pressure-rolling is the intermediate link that a hot extrusion is increased on the basis of casting-rolling, and extruding can make slab by more
Reinforce strong three-dimensional compressive stress to obtain maximum plasticity, provides uniform tissue for subsequent rolling, be conducive to magnesium alloy
Mechanical property raising.Although extrusion process can significant thinning microstructure, improve deformation after unloading ability, big ruler cannot be produced
Very little plate.
Therefore, it is necessary to novel, lightweight, high forming, alloy product convenient for production be developed, to meet under harsh conditions
Requirement, this helps to alleviate the energy and environmental problem that human society is faced.So, it is closed to fundamentally improve magnesium
These problems that gold is encountered, the present invention propose new idea and method from alloy design, rolling mill practice setting etc..Benefit
Solid solution metathesis with microelement to basis material obtains a kind of novel saturated solid solution material, it can influence matrix
The lattice constant c/a ratio of material, or change the stacking fault energy etc. of material.Meanwhile in conjunction with unique rolling mill practice, by symmetrical
Property rotary cross rolling, develop a kind of ingot casting-rolled plate.The plate has good mechanical property, especially has excellent
Different room temperature forming capacity.The present invention has certain use value and novelty,
Summary of the invention
It is related to a kind of novel magnesium alloy plate and preparation method thereof in the present invention, provides tool in a kind of room temperature
There are the magnesium alloy materials of high formability.Magnesium alloy of the invention has excellent forming property at room temperature, better than other preparations
The forming property of method alloy obtained, so that alloy preparation, manufacturing process simplify, it is a kind of room that forming property is prominent
The lower magnesium alloy materials with excellent forming property of temperature.
A kind of room temperature height forming magnesium alloy plate, which is characterized in that alloying component: select Zn, Er as main alloying
Element, additive amount are respectively Zn≤1.0wt.%, Er≤1.0wt.%, and the total quality percentage of Zn, Er element in the alloy
Number≤1.0wt.% is greater than 0%, and surplus is magnesium.
In order to obtain the preferable Mg-Zn-Er alloy of the forming property, present invention employs following preparation methods, including with
Lower step:
(1) smelting technology:
Smelting technology of the invention is, by the commercial pure magnesium (99.99%wt.%) of raw material, pure zinc (99.99wt.%) and
Mg-Er intermediate alloy (preferably Mg-30wt.%Er intermediate alloy) surface polishing, the impurity such as removal surface scale.Entire melting
Process uses gas shield, wherein N2To convey gas, SF6It is firstly added after the pre- heat abstraction moisture of crucible for protective gas
Pure magnesium, and 720 DEG C are warming up to, after magnesium pure in furnace is completely melt, pure zinc or Mg-Er intermediate alloy are sequentially added, continues to add
Then heat carries out fishing slag, casting until stirring 3min homogenizes aluminium alloy, stands 10~15min after it is completely melt;Casting
Solidification is air-cooled to room temperature in punching block afterwards;
(2) rolling mill practice:
Ingot casting is previously cut to plate, before plate is rolled, is annealed first, annealing temperature is 350-500 DEG C, is protected
Plate taking-up is then immediately placed under pre-heated roll by warm 5-30min, completes the rolling of the first passage, and rolling rate is
5-15m/min, making annealing treatment plate before then repeating and next passes, the rolling side of previous three passes
To being consistent, plate total deformation is 15-30% after 3 passes, when then carrying out the rolling of four-pass, by plate
Material coplanar be rotated by 90 ° in original rolling direction is rolled, and rolling 3 times, after 6 passes, total deformation are repeated
Amount is 30-45%;Two kinds of above-mentioned rollings of changing direction are repeated, plate is rotated by 90 ° after three passages of every rolling and carries out down three again
Secondary rolling is rolled and is alternately changed to laterally (vertically roll to);Identical annealing is all carried out before rolling per pass;Final warp
15-20 passes are crossed, sheet deformation amount is 80-95%.
Further preferably before step (2) rolling mill practice, by the resulting ingot casting of melting in 440 DEG C of heat preservation 10h, and to adding
Thermalloy carries out (75 DEG C) of warm water quenchings;Then machining that the ingot casting obtained after heat treatment is carried out to step (2), obtains plate
Material.
Substantive distinguishing features and marked improvement of the invention
(1) be prepared for a kind of novel high forming magnesium alloy materials, forming property be significantly higher than report at present it is other
Magnesium alloy.
(2) alloy has the characteristics that ingredient is simple, low in cost, economic and practical.
(3) preparation of the alloy, processing method strong operability, do not need special installation and method can be obtained high forming
The alloy material of performance.
(4) room temperature tensile intensity, the yield strength of the sheet alloy be respectively 160MPa~230MPa, 120MPa~
200MPa。
(5) the room temperature Erichsen number of the sheet alloy is 2.5-6mm, reaches good formability, this method can be directly used for
The preparation of high moulding material.
(6) present invention gained magnesium alloy plate is polycrystalline alloy, and crystal boundary is clean, and matrix has the rod-shaped reinforcing of a large amount of nanoscales.
Detailed description of the invention
The optical microstructure of Fig. 1 Mg-0.5Zn sheet alloy;
The optical microstructure of Fig. 2 Mg-0.5Er sheet alloy;
The optical microstructure of Fig. 3 Mg-0.5Zn-0.5Er sheet alloy;
Specific embodiment
Below with reference to embodiment, the present invention will be further described, but the present invention is not limited to following embodiments.
Embodiment 1
Now by the scale removals layer such as pure Zn and pure magnesium, and weigh ingredient.The mass percent of Zn is in prealloy
0.5wt.%, surplus are magnesium.Alloy carries out melting in well formula resistance furnace, and rated power is 7.5kW or so, and size of burner hearth is
550 × 600mm of Φ, and it is furnished with protective gas conveying device and PID temperature control device etc..Melting graphite crucible is having a size of internal diameter
100mm, deep 160mm, single molten alloy liquid quality is about 1.5kg.Pouring mold is mild steel metal die, the ingot casting ruler of acquisition
The very little rectangular base for being 120 × 33 × 200mm.Alloy is aoxidized and is burnt in fusion process in order to prevent, and entire fusion process is adopted
With gas shield, wherein N2To convey gas, SF6For protective gas.Alloy smelting process are as follows: after the pre- heat abstraction moisture of crucible,
It is firstly added pure magnesium, and is warming up to 720 DEG C, pure zinc is added after magnesium pure in furnace is completely melt.Continue to heat, until it is completely melt
Afterwards, stirring 3min homogenizes aluminium alloy.10~15min is stood, fishing slag, casting are then carried out.It is solidified in punching block after casting
It is air-cooled to room temperature.Then by the resulting ingot casting of melting in 440 DEG C of heat preservation 10h, and warm water (~75 DEG C) are carried out to heating alloy and are quenched
Fire.The ingot casting obtained after heat treatment is machined, the plate with a thickness of 5mm is obtained, before plate is rolled, carries out first
Annealing, keeps the temperature 5min by 400 DEG C of annealing temperature, and then plate taking-up is immediately placed in the roll for being previously heated to 400 DEG C, is completed
The rolling of first passage, rolling rate are 7m/min, and the annealing before then repeating plate continues the second passage and rolls
System, the rolling direction of previous three passes are consistent, and plate is rolled down to 3.7mm from 5mm after 3 passes, and total deformation is
26%, when carrying out the rolling of four-pass, plate is rotated by 90 ° in original rolling direction and is rolled, repeats rolling 3
Secondary, after 6 passes, plate thickness becomes 2.8mm, and deflection is 24% on the basis of the original, and total deformation is
44%.This rolling mill practice controls single pass heavy deformation in 7%-15%, by the way of tandem rolling, i.e., every rolling three
Plate is rotated by 90 ° after secondary and is rolled again, rolls and alternately changes to laterally (vertically roll to).It is all carried out before rolling per pass
Identical annealing.Eventually pass through 18 passes, plate thickness 1.1mm, deflection 78%.
The room temperature IE value of alloy are as follows: 2.99mm.
The room temperature tensile of alloy, yield strength are as follows: 174MPa, 154MPa.
Embodiment 2
Now by the scale removals layer such as Mg-Er intermediate alloy and pure magnesium, and weigh ingredient.The quality hundred of Er in prealloy
Divide than being 0.5wt.%, surplus is magnesium.Alloy carries out melting in well formula resistance furnace, and rated power is 7.5kW or so, burner hearth
Having a size of 550 × 600mm of Φ, and it be furnished with protective gas conveying device and PID temperature control device etc..Melting graphite crucible having a size of
Internal diameter 100mm, deep 160mm, single molten alloy liquid quality is about 1.5kg.Pouring mold is mild steel metal die, the casting of acquisition
Rectangular base of the ingot having a size of 120 × 33 × 200mm.Alloy is aoxidized and is burnt in fusion process in order to prevent, entire melting
Cheng Caiyong gas shield, wherein N2To convey gas, SF6For protective gas.Alloy smelting process are as follows: by the pre- heat abstraction water of crucible
After point, it is firstly added pure magnesium, and be warming up to 720 DEG C, Mg-Er intermediate alloy is added after magnesium pure in furnace is completely melt.Continue to add
Heat, until stirring 3min homogenizes aluminium alloy after it is completely melt.10~15min is stood, fishing slag, casting are then carried out.Casting
Solidification is air-cooled to room temperature in punching block afterwards.Then by the resulting ingot casting of melting in 440 DEG C of heat preservation 10h, and heating alloy is carried out
(~75 DEG C) of warm water quenchings.The ingot casting obtained after heat treatment is machined, the plate with a thickness of 5mm is obtained, plate is rolled
It before system, anneals first, 400 DEG C of annealing temperature, keeps the temperature 5min, then plate taking-up is immediately placed at and is previously heated to 400
DEG C roll in, complete the first passage rolling, rolling rate be 7m/min, then by plate repeatedly before annealing,
Continue the second passes, the rolling direction of previous three passes is consistent, and plate is rolled down to from 5mm after 3 passes
Plate is rotated by 90 ° progress when carrying out the rolling of four-pass by 3.7mm, total deformation 26% in original rolling direction
Rolling repeats rolling 3 times, and after 6 passes, plate thickness becomes 2.8mm, and deflection is on the basis of the original
24%, total deformation 44%.This rolling mill practice controls single pass heavy deformation in 7%-15%, using the side of tandem rolling
Plate is rotated by 90 ° after three passages of every rolling and rolls again by formula, roll and alternately change to laterally (vertically roll to).Per pass
Identical annealing is all carried out before secondary rolling.18 passes, plate thickness 1.1mm are eventually passed through, deflection is
78%.
The IE value of alloy are as follows: 5.79mm.
The room temperature tensile of alloy, yield strength are as follows: 178MPa, 150MPa.
Embodiment 3
Now by scale removals layers such as Mg-Er intermediate alloy, pure Zn and pure magnesium, and weigh ingredient.In prealloy Zn and
The mass percent of Er is 0.5wt.%, and the total amount of alloying element is 1wt.%, and surplus is magnesium.Alloy in well formula resistance furnace into
Row melting, rated power are 7.5kW or so, and size of burner hearth is 550 × 600mm of Φ, and equipped with protective gas conveying device and
PID temperature control device etc..Melting graphite crucible is about having a size of internal diameter 100mm, deep 160mm, single molten alloy liquid quality
1.5kg.Pouring mold is mild steel metal die, and the cast ingot dimension of acquisition is the rectangular base of 120 × 33 × 200mm.In order to prevent
Alloy is aoxidized and is burnt in fusion process, and entire fusion process uses gas shield, wherein N2To convey gas, SF6For protection
Gas.Alloy smelting process are as follows: after the pre- heat abstraction moisture of crucible, pure magnesium is firstly added, and be warming up to 720 DEG C, to pure in furnace
After magnesium is completely melt, pure zinc and Mg-Er intermediate alloy are sequentially added.Continue to heat, until stirring 3min makes to close after it is completely melt
Golden liquid homogenization.10~15min is stood, fishing slag, casting are then carried out.Solidification is air-cooled to room temperature in punching block after casting.Then
By the resulting ingot casting of melting in 440 DEG C of heat preservation 10h, and (~75 DEG C) of warm water quenchings are carried out to heating alloy.It will be obtained after heat treatment
The ingot casting obtained is machined, and is obtained the plate with a thickness of 5mm, before plate is rolled, is annealed first, annealing temperature
400 DEG C, 5min is kept the temperature, then plate taking-up is immediately placed in the roll for being previously heated to 400 DEG C, completes rolling for the first passage
System, rolling rate are 7m/min, and the annealing before then repeating plate continues the second passes, previous three passes
Rolling direction is consistent, and plate is rolled down to 3.7mm from 5mm after 3 passes, and total deformation 26% carries out the 4th
When the rolling of passage, plate is rotated by 90 ° in original rolling direction and is rolled, repeated rolling 3 times, rolled by 6 passages
After system, plate thickness becomes 2.8mm, and deflection is 24% on the basis of the original, total deformation 44%.This rolling mill practice
Single pass heavy deformation is controlled in 7%-15%, by the way of tandem rolling, i.e., is rotated by 90 ° plate after three passages of every rolling
It is rolled again, rolls and alternately change to laterally (vertically roll to).Identical annealing is all carried out before rolling per pass.Most
Pass through 18 passes, plate thickness 1.1mm, deflection 78% eventually.The IE value of alloy are as follows: 5.67mm.
The room temperature tensile of alloy, yield strength are as follows: 215MPa, 200MPa.