CN104249136B - The continuous semisolid casting of a kind of belt magnesium alloy strip blank device - Google Patents
The continuous semisolid casting of a kind of belt magnesium alloy strip blank device Download PDFInfo
- Publication number
- CN104249136B CN104249136B CN201410447981.4A CN201410447981A CN104249136B CN 104249136 B CN104249136 B CN 104249136B CN 201410447981 A CN201410447981 A CN 201410447981A CN 104249136 B CN104249136 B CN 104249136B
- Authority
- CN
- China
- Prior art keywords
- casting
- magnesium alloy
- melt
- continuous
- strip blank
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Continuous Casting (AREA)
- Metal Rolling (AREA)
Abstract
The present invention relates to materials processing engineering field, be specifically related to the continuous semisolid casting of a kind of belt magnesium alloy strip blank device and method. The device of the continuous semisolid casting of a kind of belt of the present invention magnesium alloy strip blank, is characterized in that described apparatus structure comprises: two groups be oppositely arranged, the casting wheels of opposite direction rotating; Two are wrapped in respectively the steel band in casting wheels outside, between described two steel bands, form v font casting region; Be arranged at the feeding device in casting region; Be positioned at the damping block of feeding device below; Be arranged at the water mist cooling apparatus in steel band outside. Amount of plastic deformation when the present invention can further strengthen casting, can be 30% left and right from traditional casting amount of plastic deformation, bring up to more than 60%, effectively strengthen the amount of plastic deformation of casting operation, realize the heat energy while making full use of casting, magnesium alloy materials has been carried out to hot-working.
Description
Technical field
The present invention relates to materials processing engineering field, be specifically related to the continuous semisolid casting of a kind of belt magnesium alloy strip blank device.
Background technology
Magnesium alloy board has that quality is light, electromagnetic shielding good, has broad application prospects. Therefore, be a kind of desirable function and structure-integrated engineering material, be particularly applied in light to material requirements quality, need to prevent electromagnetic interference and damping field, as aspects such as communications and transportation, mobile communication, hand-operated tools.
But at normal temperatures, the plastic deformation ability of magnesium alloy is very limited, has influence on to a certain extent its application. Researching and developing effective magnesium alloy materials New Machining Technology is the important means that promotes magnesium alloy materials application.
Semisolid metal processing technology is a new technology of researching and developing in the last few years, it is in metal solidification process, by the control of vigorous stirring or process of setting, the subglobose solid phase particles of solid phase components obtains suspending equably in a kind of liquid metal mother liquor, it is semi-solid metal slurry, there is good mobility, be easy to by the product of the shaping of common process method, shape matching complexity. Meanwhile, the product of acquisition has non-dendritic structure structure, and therefore the mechanical property of product is greatly improved.
Casting is the effective ways of preparing magnesium alloy strip blank, the two roller casting modes that adopt in prior art more, but, two traditional roller castings are subject to the restriction of dimension of roller, drafts is restricted, traditional plastic deflection is 30% left and right, and casting magnesium alloy strip blank exists the problems such as efficiency is low, strip quality is undesirable.
Summary of the invention
The present invention is directed to the deficiency of above-mentioned prior art, the device of the continuous semisolid casting of a kind of belt magnesium alloy strip blank is provided, to improve quality and the production efficiency of continuous casting and rolling magnesium alloy plate carries product.
The present invention is achieved by the following technical solutions:
The device of the continuous semisolid casting of a kind of belt of the present invention magnesium alloy strip blank, it is characterized in that described apparatus structure comprises: two groups be oppositely arranged, the casting wheels of opposite direction rotating, each described group casting wheel group structure comprises: continuous casting and rolling driving wheel, be arranged on the first driven pulley of continuous casting and rolling driving wheel top, be arranged on the steel belt tensioning wheel of the first driven pulley side, the below of described steel belt tensioning wheel is fixed with pedestal, between pedestal and steel belt tensioning wheel, connects by tensioning spring; And be arranged on the second driven pulley of pedestal below; Be wound with respectively a steel band in described two groups of casting wheels outside, between two described steel bands, form V font casting region; In the V font casting region forming between two steel bands, be provided with feeding device, described feeding device top is storage bin, and bottom is feed mouth; Be positioned at feeding device below and be provided with damping block; And be arranged on the water mist cooling apparatus inside steel band, and described water mist cooling apparatus comprises one or more water smoke cooling jets, described water smoke cooling jet, towards steel band, becomes the angle of 15～20 ° with steel band.
According to above-mentioned device, it is characterized in that the structure of described feed mouth comprises: two blocks of side plates that are oppositely arranged, between described biside plate, horizontal direction is uniformly distributed with several branching blocks, and described branching block is taper.
According to above-mentioned device, the structure that it is characterized in that described feed mouth comprises: two cover plates that are oppositely arranged, between described two cover plates, be provided with melt inlet, below melt inlet, be provided with the branching block of inverted trapezoidal, be evenly equipped with triangle branching block in inverted trapezoidal branching block both sides, or below melt inlet, be provided with uniform T-shaped branching block.
According to above-mentioned device, it is characterized in that described damping block adopts high-strength refractory material or high temperature alloy manufacture, the middle part of described damping block has through hole, and the two sides of damping block have groove。
According to above-mentioned device, it is characterized in that the mode that described water mist cooling apparatus employing pressure-air and water smoke are cooling, the intensity of cooling (heat loss through convection coefficient) of described water mist cooling apparatus regulates within the scope of 20 ~ 2000W/ ㎡ K.
According to above-mentioned device, it is characterized in that described water smoke cooling jet is 2～6.
According to above-mentioned device, it is characterized in that described apparatus structure is also provided with melt protecting cover, described melt protecting cover covers on the storage bin of feeding device, is provided with air inlet pipe and feed pipe on melt protecting cover.
According to above-mentioned device, it is characterized in that described apparatus structure is also provided with leveling device, described leveling device is arranged on the lower end of feed pipe.
According to above-mentioned device, it is characterized in that the size of the magnesium alloy slab of casting: width is 200mm～800mm, thickness is 3mm～6mm.
Useful technique effect of the present invention: the invention provides the device of the continuous semisolid casting of a kind of belt magnesium alloy strip blank, have the following advantages:
(1) adopt steel band casting can increase the contact length of melt and cooling steel band, improve intensity of cooling, improve roll casting speed;
Simultaneously, the melt of the rapid cooling droplets adjacent inner surface of energy, make it to solidify and be attached on steel band and grow up, come off when being subject to the impact of contiguous damping block, melt is becoming cooling particle, and is subject to constantly cooling impact, continues to grow up, become semi-solid melt (slurry), realize the process of dynamic system for semi solid slurry;
(2) damping block has been installed below feeding device, can have been promoted that the metallic crystal particle of cooled and solidified on steel band inner surface is de-
Fall, in melt, form mass crystallization core, promote that melt is even, rapid crystallization, and generate subglobose non-dendritic structure; In the left and right of damping block, outer surface has groove, increases the resistance of flowing through between block outside and steel band inner side, promotes at the larger particle detachment of steel strip surface solidification and crystallization, becomes the crystallization nuclei in melt;
(3) water mist cooling apparatus has high intensity of cooling and cooling uniformity, and has very strong intensity of cooling and adjusting
Ability; The intensity of cooling (heat loss through convection coefficient) of steel band outer surface can be at 20 ~ 2000(W/ ㎡ K) regulate in scope, in the time adopting velocity air cooling, the heat loss through convection coefficient of steel band outer surface is 20W/ ㎡ K; In the time adopting pressure-air to add water fog cooling, the heat loss through convection coefficient of steel band outer surface can reach 2000W/ ㎡ K; Water mist cooling apparatus comprises multiple nozzles, and nozzle becomes the angle of 15～20 ° with steel band, be conducive to the discharge of water smoke and steam;
(4) for improving the quality of products, the consumption of saving and protection gas, can also adopt enclosed running gate system, and magnesium alloy is molten
Body injects the feeding device with protective cover by feed pipe, is filled with appropriate protective gas under protective cover, and metal bath surface is protected;
(5) amount of plastic deformation can further strengthen casting time, can be 30% left and right from traditional casting amount of plastic deformation, improves
To more than 60%, effectively strengthen the amount of plastic deformation of casting operation, realize the heat energy while making full use of casting, magnesium alloy materials is carried out to hot-working.
Brief description of the drawings
Fig. 1 is structural representation of the present invention;
Fig. 2 is the arrangement schematic diagram of nozzle;
Fig. 3 is the first structural representation of feed mouth;
Fig. 4 is the second structural representation of feed mouth;
Fig. 5 is the third structural representation of feed mouth;
Fig. 6 is the structural representation of damping block;
Fig. 7 is the technical process schematic diagram that uses apparatus of the present invention;
Fig. 8 is structure and the magnesium alloy fused mass process of setting schematic diagram of semisolid continuous casting and rolling crystal region;
Fig. 9 is the partial enlarged drawing of Fig. 8;
Figure 10 is the outline drawing that AZ91D alloy rolling slab carries out further rolling processing acquisition sample;
Figure 11 is the outline drawing that AZ318 alloy rolling slab carries out further rolling processing acquisition sample;
Figure 12 simplifies the geometrical model of rear foundation and the grid chart of division to technique of the present invention;
Figure 13 is the temperature field distribution map of different entrance melt temperatures continuous casting zone;
Figure 14 is different entrance melt temperature solid volume fraction distribution maps;
Figure 15 is the temperature field distribution map of different roll casting speeds continuous casting zone;
Figure 16 is different roll casting speed melt solid volume fraction distribution maps.
Detailed description of the invention
Shown in Fig. 1-Fig. 6, the device of the continuous semisolid casting of a kind of belt magnesium alloy strip blank, described apparatus structure comprises: two groups be oppositely arranged, the casting wheels 1 of opposite direction rotating, each described group casting wheel group structure comprises: continuous casting and rolling driving wheel 2, be arranged on the first driven pulley 3 of continuous casting and rolling driving wheel top, the steel belt tensioning wheel 4 that is arranged on the first driven pulley side, the below of described steel belt tensioning wheel is fixed with pedestal 5, between pedestal and steel belt tensioning wheel, connects by tensioning spring 6; And be arranged on the second driven pulley 7 of pedestal below; Be wound with respectively a steel band 8 in described two groups of casting wheels outside, between two described steel bands, form V font casting region 9; In the V font casting region forming between two steel bands, be provided with feeding device 10, described feeding device top is storage bin, and bottom is feed mouth; Be positioned at feeding device below and be provided with damping block 11; And be arranged on the water mist cooling apparatus inside steel band, and described water mist cooling apparatus comprises one or more water smoke cooling jets 12, described water smoke cooling jet, towards steel band, becomes the angle of 15～20 ° with steel band.
A device for the continuous semisolid casting of belt magnesium alloy strip blank, the structure of described feed mouth comprises: two blocks of side plates that are oppositely arranged 13, between described biside plate, horizontal direction is uniformly distributed with several branching blocks 14, and described branching block is taper. In the time that cast-rolled block width is 200mm, can select the distribution feed mouth that branching block is as shown in Figure 3 taper.
The device of the continuous semisolid casting of a kind of belt magnesium alloy strip blank, the structure of described feed mouth comprises: two cover plates that are oppositely arranged 15, between described two cover plates, be provided with melt inlet 16, below melt inlet, be provided with the branching block 17 of inverted trapezoidal, be evenly equipped with triangle branching block 18 in inverted trapezoidal branching block both sides, or below melt inlet, be provided with uniform T-shaped branching block 19. In the time that cast-rolled block width is 800mm, can select the distribution feed mouth that branching block is as shown in Figure 5 T-Type structure.
A device for the continuous semisolid casting of belt magnesium alloy strip blank, described damping block adopts high-strength refractory material or high temperature alloy manufacture, and the middle part of described damping block has the through hole 20 that ensures that melt passes through smoothly, and the two sides of damping block have groove 21。
The device of the continuous semisolid casting of a kind of belt magnesium alloy strip blank, the mode that described water mist cooling apparatus employing pressure-air and water smoke are cooling, the intensity of cooling (heat loss through convection coefficient) of described water mist cooling apparatus regulates within the scope of 20 ~ 2000W/ ㎡ K, in the time adopting velocity air cooling, the heat loss through convection coefficient of steel band outer surface is 20W/ ㎡ K; In the time adopting pressure-air to add water fog cooling, the heat loss through convection coefficient of steel band outer surface can reach 2000W/ ㎡ K.
A device for the continuous semisolid casting of belt magnesium alloy strip blank, described water smoke cooling jet is 2～6.
The device of the continuous semisolid casting of a kind of belt magnesium alloy strip blank; described apparatus structure is also provided with melt protecting cover 22; described melt protecting cover covers on the storage bin of feeding device; on melt protecting cover, be provided with air inlet pipe 23 and feed pipe 24; under described melt protecting cover, be filled with appropriate protective gas, protective gas is taking carbon dioxide as main mist.
A device for the continuous semisolid casting of belt magnesium alloy strip blank, described apparatus structure is also provided with leveling device 25, and described leveling device is arranged on the lower end of feed pipe.
A device for the continuous semisolid casting of belt magnesium alloy strip blank, the size of the magnesium alloy slab 26 of casting: width is 200mm～800mm, thickness is 3mm～6mm.
As shown in Fig. 7-Fig. 9, the course of work of the device of the continuous semisolid casting of a kind of belt magnesium alloy strip blank is: magnesium alloy fused mass injects feeding device by feed pipe, and under the control of leveling device, keeps the setting height of liquid level; Meanwhile, be filled with appropriate protective gas under protective cover, metal bath surface will be protected. Under the steel band that magnesium alloy fused mass in feeding device moves down two continuous casting and rolling driving wheels rotations drives, flow downward; Most of melt is to flow downward by the intermediate throughholes of damping block; Small part melt is to flow downward between the gap, both sides by damping block, and this part melt is subject to the cooling rapidly of cold steel band, is set in steel band inner surface, as the A district of indication in Fig. 9, along with steel band moves down and constantly grows up. When the magnesium alloy particles of solidifying is grown up to certain size, owing to being subject to the effect of gravity and the impact of damping link stopper, split away off from steel strip surface, get back in the melt of melting, as the B district of indication in Fig. 9. Due to the cooling effect of the cold steel band in both sides, melt at the simultaneous temperature flowing downward also in continuous reduction, be subject to a large amount of tiny solidified particle impact splitting away off from steel strip surface simultaneously, the fine particle having solidified is got back to the impact that becomes the core of melt solidifying in melt, and the magnesium alloy (referring to flow into the C district of indication in Fig. 9) in this district is in semi-solid state; Under the drive that continues to move downward at the cold steel band in both sides, solid volume fraction, in continuous increase, is finally all frozen into and has the solid-state of subsphaeroidal non-dendritic structure structure from the top down, enters indication D district in Fig. 9. The magnesium alloy solidifying completely enters in the middle of two continuous casting and rolling driving wheels under the drive of the cold steel band in both sides, under the pressure rolling of two continuous casting and rolling driving wheels, produces plastic deformation, completes strip casting process. Due to the magnesium alloy that has adopted steel band to be wrapped in to solidify be rolled (the one,, the magnesium alloy just having solidified is in very high temperature, resistance of deformation is little; The 2nd,, steel band and to solidify the contact length of magnesium alloy larger, the tractive of generation is also larger, the magnesium alloy solidifying can be brought into and is rolled wheel), therefore can realize larger amount of plastic deformation, test shows to reach 60% left and right.
Embodiment 1: it is the AD91 magnesium alloy strip blank that 600mm, thickness are 6mm that application this patent is prepared width.
1, relevant parameters is set and related data
(1) relevant parameters is set
Set: cast-rolled block width is 600mm; Thickness is 6mm; Roll casting speed is 2m/min; Cast-rolled block outlet temperature is 300 DEG C; Inject melt temperature and be set as 740 DEG C;
(2) related data
The chemical composition of AZ91D magnesium alloy is as shown in table 1. About the physical parameter of experiment material is shown in Table 2.
The chemical composition of table 1AZ91D magnesium alloy
Table 2 is about the physical parameter of experiment material
(3) key data is calculated
1) volume and amount of metal that the casting system unit interval flows out
V=60(cm)×0.4(cm)×200(cm/min)=4800(cm3/min)；
W=V×1.74=4800(cm3/min)×1.74(g/cm3)=8352g=8.352kg;
2) need to conduct heat (740 DEG C of the melt inlet mean temperatures that; 300 DEG C of slab outlet temperatures)
Q=W×（（740-300）×0.25+8.8）=8352×118.8=992217.6cal=992.2176Kcal
3) surface radiating area (taking into account system heat transfer effect, 1.2 times of establishing surface radiating area and be minimal-contact area)
S=1.2×2×60(cm)×8.2(cm)=1180(cm2)
4) heat radiation of steel band outer surface requires (be coefficient of heat transfer, namely need the intensity of cooling reaching), heat loss through convection formula q=Q/S=λ (TSolid-TGas); If the mean temperature of steel band outer surface is 600 DEG C, 100 DEG C of reflux gas temperature.
λ=q/（TSolid-TGas））=（60×992217.6）/（1182×（600-100））=100.7328（h·kcal/m2k）
（1(h·kcal/m2k）=1.16279（w/m2·K）)
λ=100.7328（h·kcal/m2k）×1.16279=137.1311（w/m2·K）
λ=100.7328 < < 1000 (maximum one of cooling system)
Calculating shows, the cooling device of employing can meet the intensity of cooling of normal casting.
2, the configuration of alloy and melting
First according to the composition of AZ91D alloy, (referring to table 1) joined, got the raw materials ready, in smelting furnace by metal magnesium ingot, intermediate alloy or the metallic addition got ready, magnesium alloy fused mass after smelting furnace fusing is by skimming, stirring, after analysis composition is qualified, temperature is controlled to 730-755 DEG C and imports standing furnace, liquid leaves standstill in standing furnace, after refining, control standing furnace melt temperature 720-745 DEG C.
3, cast
First, casting and rolling device is started, adjust to the 1.5-2 of setting roll casting speed doubly; And start cooling device, adjust to lower cooldown rate. Then, the magnesium alloy fused mass after refining is injected magnesium alloy fused mass by feed pipe to the feeding device of casting and rolling the production line, and keep as much as possible liquid level in feeding device to be stabilized in 3/4ths of feeding device height. Meanwhile, inject protective gas by air inlet, keep there is appropriate protective gas under protective cover, melt liquid level metal is not oxidized.
4, stablize drawing and batching of roll casting sheet
Setting up normal strip casting process is to carry out adjustment repeatedly to technological parameter, just can be stabilized to the technological parameter of setting, is commonly referred to riser. For vertical upper note formula casting and rolling machine, melt enters in casting district from the bottom up, in the time of riser, relies on to roll to take turns to rotate melt is taken out of and rolled wheel seam. Starting to flow into the melt in casting district, due to the effect of itself gravity, will be set in feed mouth, normally ejecting plate. So, start to start and need to accelerate roll casting speed the material strip solidifying is gone out, more progressively drop to setting roll casting speed, realize strip casting process; Adjust intensity of cooling simultaneously, line of solidification is adjusted to the position of setting, realize the amount of plastic deformation of setting.
Roll casting sheet leaves continuous casting and rolling driving wheel, through hauling machine feeding machine row, cuts away head, to coiling machine, is rolled into the large volume of required diameter. In the time that strip blank reaches intended size, unload volume, then restart next volume.
5, solidifying and deformation process of casting district
(1) magnesium alloy fused mass in feeding device, under the rotation of two continuous casting and rolling driving wheels, under the driving force that drive steel band moves down, flows downward; Most of melt is to flow downward by the intermediate throughholes of damping block; Small part melt is to flow downward between the gap, both sides by damping block, and this part melt is subject to the cooling rapidly of cold steel band, is set in steel band inner surface, as the A district of indication in Fig. 9, along with steel band moves down and constantly grows up; When the magnesium alloy particles of solidifying is grown up to certain size, owing to being subject to the effect of gravity and the impact of damping link stopper, split away off from steel strip surface, get back in the melt of melting, as the B district of indication in Fig. 9.
(2) due to the cooling effect of the cold steel band in both sides, melt also in continuous reduction, is subject to a large amount of tiny solidified particle impact splitting away off from steel strip surface at the simultaneous temperature flowing downward simultaneously; The fine particle having solidified is got back to the core that becomes melt solidifying in melt, in constantly lowering the temperature, grows up rapidly, and the magnesium alloy (flowing into indication C district in Fig. 9) in this district is in semi-solid state; Under the drive that continues to move downward at the cold steel band in both sides, solid volume fraction, in continuous increase, is finally all frozen into and has the solid-state of subsphaeroidal non-dendritic structure structure from the top down, enters indication D district in Fig. 9.
(3) magnesium alloy solidifying completely enters between two continuous casting and rolling driving wheels under the drive of the cold steel band in both sides, under the pressure rolling of two continuous casting and rolling driving wheels, produces plastic deformation, completes strip casting process. Because the magnesium alloy that has adopted steel band to be wrapped in to solidify is rolled, therefore can realize larger amount of plastic deformation, test shows to reach 60% left and right.
6, the mechanical property of the test of semi-solid casting rolling AZ 91 D alloy material and cast-rolled block
Adopt simple test method, carried out the experimental study of semi-solid casting rolling AZ 91 D alloy material, result of study shows: this patent of invention has very strong actual application value. AZ91D alloy slab after semisolid casting carries out sample that further rolling processing obtains as shown in figure 10, and its mechanical property is as shown in table 3.
The processing characteristics of the AZ91D alloy slab after the casting of table 3 semisolid
Embodiment 2: application this patent is prepared the AZ31B magnesium alloy strip blank that width is 300mm, thickness 3mm.
1, relevant parameters is set and related data
(2) relevant parameters is set
Set: cast-rolled block width is 300mm; Thickness is 3mm; Roll casting speed is 2.5m/min; Cast-rolled block outlet temperature is 300 DEG C; Inject melt temperature and be set as 740 DEG C;
(2) related data
The chemical composition of AZ31B magnesium alloy is as shown in table 4. About the physical parameter of experiment material is shown in Table 2.
The chemical composition of table 4AZ31B magnesium alloy
(3) key data is calculated
1) volume and amount of metal that the casting system unit interval flows out
V=30(cm)×0.3(cm)×250(cm/min)=2250(cm3/min)；
W=V×1.74=2250(cm3/min)×1.74(g/cm3)=3915g=3.915kg;
2) need to conduct heat (740 DEG C of the melt inlet mean temperatures that; 300 DEG C of slab outlet temperatures)
Q=W×（（740-300）×0.25+8.8）=3915×118.8=461970cal=461.97Kcal
3) surface radiating area (taking into account system heat transfer effect, 1.2 times of establishing surface radiating area and be minimal-contact area)
S=1.2×2×60(cm)×8.2(cm)=1180(cm2)
4) heat radiation of steel band outer surface requires (be coefficient of heat transfer, namely need the intensity of cooling reaching), heat loss through convection formula q=Q/S=λ (TSolid-TGas); If the mean temperature of steel band outer surface is 600 DEG C, 100 DEG C of reflux gas temperature.
λ=q/（TSolid-TGas））=（60×461970）/（1182×（600-100））=46.90051（h·kcal/m2k）
（1(h·kcal/m2k）=1.16279（w/m2·K）)
λ=46.90051（h·kcal/m2k）×1.16279=54.53544（w/m2·K）
λ=46.90051 < < 1000 (maximum one of cooling system)
Calculating shows, the cooling system of employing can meet the intensity of cooling of normal casting.
2, the configuration of alloy and melting
First according to the composition of AZ31B alloy, (referring to table 4) joined, got the raw materials ready, in smelting furnace by metal magnesium ingot, intermediate alloy or the metallic addition got ready, magnesium alloy fused mass after smelting furnace fusing is by skimming, stirring, after analysis composition is qualified, temperature is controlled to 730-755 DEG C and imports standing furnace, liquid leaves standstill in standing furnace, after refining, control standing furnace melt temperature 720-745 DEG C.
3, cast
First, casting and rolling machine is started, adjust to the 1.5-2 of setting roll casting speed doubly; And start cooling device, adjust to lower cooldown rate. Then, the magnesium alloy fused mass after refining is injected magnesium alloy fused mass by feed pipe to the feeding device of casting and rolling the production line, and keep as much as possible liquid level in feeding device to be stabilized in 3/4ths of feeding device height. Meanwhile, inject protective gas by air inlet, keep there is appropriate protective gas under protective cover, melt liquid level metal is not oxidized.
4, stablize drawing and batching of roll casting sheet
Setting up normal strip casting process is to carry out adjustment repeatedly to technological parameter, just can be stabilized to the technological parameter of setting, is commonly referred to riser. For vertical upper note formula casting and rolling machine, melt enters in casting district from the bottom up, in the time of riser, relies on continuous casting and rolling driving wheel to take melt out of wheel seam. Starting to flow into the melt in casting district, due to the effect of itself gravity, will be set in feed mouth, normally ejecting plate. So, start to start and need to accelerate roll casting speed the material strip solidifying is gone out, more progressively drop to setting roll casting speed, realize strip casting process; Adjust intensity of cooling simultaneously, line of solidification is adjusted to the position of setting, realize the amount of plastic deformation of setting.
Roll casting sheet leaves continuous casting and rolling driving wheel, through hauling machine feeding machine row, cuts away head, to coiling machine, is rolled into the large volume of required diameter, in the time that strip blank reaches intended size, unloads volume, then restarts next volume.
5, solidifying and deformation process of casting district
(1) magnesium alloy fused mass in feeding device, under the rotation of two continuous casting and rolling driving wheels, under the driving force that drive steel band moves down, flows downward; Most of melt is to flow downward by the intermediate throughholes of damping block; Small part melt is to flow downward between the gap, both sides by damping block, and this part melt is subject to the cooling rapidly of cold steel band, is set in steel band inner surface, as the A district of indication in Fig. 9, along with steel band moves down and constantly grows up; When the magnesium alloy particles of solidifying is grown up to certain size, owing to being subject to the effect of gravity and the impact of damping link stopper, split away off from steel strip surface, get back in the melt of melting, as the B district of indication in Fig. 9.
(2) due to the cooling effect of the cold steel band in both sides, melt also in continuous reduction, is subject to a large amount of tiny solidified particle impact splitting away off from steel strip surface at the simultaneous temperature flowing downward simultaneously; The fine particle having solidified is got back to the core that becomes melt solidifying in melt, in constantly lowering the temperature, grows up rapidly, and the magnesium alloy (flowing into indication C district in Fig. 9) in this district is in semi-solid state; Under the drive that continues to move downward at the cold steel band in both sides, solid volume fraction, in continuous increase, is finally all frozen into and has the solid-state of subsphaeroidal non-dendritic structure structure from the top down, enters indication D district in Fig. 9.
(3) magnesium alloy solidifying completely enters between two continuous casting and rolling driving wheels under the drive of the cold steel band in both sides, under the pressure rolling of two continuous casting and rolling driving wheels, produces plastic deformation, completes strip casting process. Because the magnesium alloy that has adopted steel band to be wrapped in to solidify is rolled, therefore can realize larger amount of plastic deformation, test shows to reach 60% left and right.
6, the mechanical property of the test of semisolid casting AZ31B alloy material and cast-rolled block
Adopt simple test method, carried out the experimental study of semisolid casting AZ31B alloy material, result of study shows: this patent of invention has very strong actual application value. AZ31B alloy slab after semisolid casting carries out sample that further rolling processing obtains as shown in figure 11, and its mechanical property is as shown in table 5.
The processing characteristics of the AZ31B alloy slab after the casting of table 5 semisolid
Embodiment 3: the process of setting of numerical simulation AZ91D magnesium alloy continuous casting and rolling.
1. general introduction
In magnesium alloy thin plate and band continuous casting and rolling process, flow behavior and the temperature of metal in molten bath is closely related, the temperature of melt and distribute again to roll the mobile relevant of wheel, melt, while melt variations in temperature relevant to its state. The heat transfer problem of melt and/or Cast Strip base is strip casting process major issue, and it directly has influence on the position of the final solidifying front of continuous casting material, closely related for the quality of controlling continuous casting material. Therefore adopting Numerical Method Study changes in process parameters to have very important significance on the impact of metal flow and coagulating property.
2. main software and the relevant parameter of application in simulation
Adopt fluid analysis software FLOW3D to carry out numerical simulation to the process of setting of AZ91D magnesium alloy continuous casting and rolling technique, study respectively the impacts of technological parameter on metal flow and coagulating property such as entrance slurry temperature, roll casting speed, acquired results is Optimizing Process Parameters better, thereby provides basic data for the casting suitability for industrialized production of two castings wheel strip semi-solid magnesium alloys.
Flow mobile the belonging to the incompressible unstable state of becoming sticky property of Free Surface of metal solidification process. Describe semi-solid alloy flow equation and mainly contain mass-conservation equation, momentum conservation equation, energy equation and volume function equation.
The process of setting of semi-solid-state metal continuous casting and rolling technique is a Unsteady Heat Transfer process with phase transformation. Along with the carrying out of process of setting, melt, from liquid phase to semisolid, further changes pure solid phase into by the semi solid slurry of solid-liquid, in transition process, will discharge a large amount of latent heats. So-called latent heat refers to alloy molten solution from liquidus temperature to solidus temperature, completes liberated heat in the process of setting from liquid phase to solid transformation. The method of processing latent heat has temperature recovery method (or claiming temperature compensation act), effective method of specific heat (claiming again equivalent method of specific heat or method of specific heat of equal value), Enthalpy method, imaginary heat flow method etc., here adopt Enthalpy method, consider latent heat by the enthalpy variation with temperature of definition material.
Show according to existing result of study, the rheological behaviour of semi-solid-state metal is mainly subject to the impact of following factors: form and the degree of agglomeration etc. of shear rate, solid volume fraction, solid phase particle. AvailableFormula statement; When alloy melt is in the time flowing through roll gap, apparent viscosity is relevant to shear rate and fluid temperature (F.T.), therefore in FLOW3D, describes non-newtonian fluid with Carreau model. Result of study shows: semi-solid magnesium alloy has strong shear shinning characteristic, and the relation of its apparent viscosity and shear rate is obeyed Power-law law, and index n approaches 0.65 in the time of low shear rate, and approaches 0.95 in the time of high-rate of shear.
3. device parameter and analog parameter
(1) device parameter and simulated conditions
Device parameter and simulated conditions that research institute uses are as shown in table 6.
Table 6 device parameter and simulated conditions
(2) physical parameter of simulation material
Material selection AZ91D magnesium alloy in analog study, its physical property is shown in Table 7, and supposes that properties of materials is constant in this research, and research from now on can be considered the temperature variant function of these physical properties.
The thermophysical property of table 7AZ91D alloy
(3) geometrical model is set up and grid division
According to above set up numerical model, continuous casting and rolling technique is simplified to the geometrical model of rear foundation and the grid of division as shown in figure 12.
4. numerical simulation result
Setting continuous-casting conditions is as follows: strip roll casting speed=1, slurry inlet velocity=0.05, wheel seam=4, melt pool height=20. In analog computation, first AZ91D magnesium alloy semisolid slurry enters liquid pool from porch, the right, now do not consider to roll the impact of wheel temperature, in the time that flow field, continuous casting zone enters stable state, use the restart function in FLOW3D, the temperature boundary condition of wheel is rolled in setting, makes semi solid slurry start to solidify under the cooling effect of rolling wheel. Result a period of time, casting process enters the stabilization sub stage, thereby has obtained the temperature field of continuous casting zone and the distribution of solid volume fraction when acquisition is stablized.
(1) temperature field of different melt temperature continuous casting zone distributes and solid volume fraction distribution
Figure 13-Figure 14 shows that entrance melt temperature is respectively 825、830、835、840、845、850Temperature field and solid volume fraction that continuous casting and rolling reaches continuous casting zone while stablizing distribute. As can be seen from the figure, the position influence in the temperature field of the difference of entrance slurry temperature to wheel seam place alloy melt and casting district is little, but larger on the temperature field in molten bath and solid volume fraction impact.
(2) impact of roll casting speed on casting zone position
Roll casting speed refers to the continuous cool time of rolling wheel alloy melt, the i.e. cooling degree to melt. Figure 15-Figure 16 shows that roll casting speed=0.6、0.8、1、1.2Time continuous casting zone temperature field distribute and the variation of casting zone position. As can be seen from Figure, position and the Temperature Distribution of different roll casting speeds to casting district has a significant impact, and roll casting speed is less, and casting zone position is longer, and this is also consistent with actual experiment situation.
5. conclusion
(1) intensity of cooling directly has influence on the temperature of calculating inlet region melt, also will be distributed with considerable influence to the temperature field in molten bath and solid volume fraction.
(2) position and the Temperature Distribution of different roll casting speeds to casting district also has a significant impact, and roll casting speed is less, and casting zone position is longer, and this is also consistent with actual experiment situation.
(3) melt with roll part that wheel (steel band) contacts will be rapidly cooling, solidify, and in movement, hindered and come off, become the crystallization nuclei in melt.
Claims (8)
1. the device of the continuous semisolid casting of a belt magnesium alloy strip blank, it is characterized in that described apparatus structure comprises: two groups be oppositely arranged, the casting wheels of opposite direction rotating, each described group casting wheel group structure comprises: continuous casting and rolling driving wheel, be arranged on the first driven pulley of continuous casting and rolling driving wheel top, be arranged on the steel belt tensioning wheel of the first driven pulley side, the below of described steel belt tensioning wheel is fixed with pedestal, between pedestal and steel belt tensioning wheel, connects by tensioning spring; And be arranged on the second driven pulley of pedestal below; Be wound with respectively a steel band in described two groups of casting wheels outside, between two described steel bands, form V font casting region; In the V font casting region forming between two steel bands, be provided with feeding device, described feeding device top is storage bin, and bottom is feed mouth; Be positioned at feeding device below and be provided with damping block; And be arranged on the water mist cooling apparatus inside steel band, and described water mist cooling apparatus comprises one or more water smoke cooling jets, described water smoke cooling jet, towards steel band, becomes the angle of 15～20 ° with steel band.
2. the device of the continuous semisolid casting of a kind of belt according to claim 1 magnesium alloy strip blank, the structure that it is characterized in that described feed mouth comprises: two blocks of side plates that are oppositely arranged, between described biside plate, horizontal direction is uniformly distributed with several branching blocks, and described branching block is taper.
3. the device of the continuous semisolid casting of a kind of belt according to claim 1 magnesium alloy strip blank, the structure that it is characterized in that described feed mouth comprises: two cover plates that are oppositely arranged, between described two cover plates, be provided with melt inlet, below melt inlet, be provided with the branching block of inverted trapezoidal, be evenly equipped with triangle branching block in inverted trapezoidal branching block both sides, or below melt inlet, be provided with uniform T-shaped branching block.
4. the device of the continuous semisolid casting of a kind of belt according to claim 1 magnesium alloy strip blank, it is characterized in that described damping block adopts high-strength refractory material or high temperature alloy manufacture, the middle part of described damping block has through hole, and the two sides of damping block have groove。
5. the device of the continuous semisolid casting of a kind of belt according to claim 1 magnesium alloy strip blank, it is characterized in that the mode that described water mist cooling apparatus employing pressure-air and water smoke are cooling, the intensity of cooling of described water mist cooling apparatus is that heat loss through convection coefficient regulates within the scope of 20 ~ 2000W/ ㎡ K.
6. the device of the continuous semisolid casting of a kind of belt according to claim 1 magnesium alloy strip blank, is characterized in that described water smoke cooling jet is 2～6.
7. the device of the continuous semisolid casting of a kind of belt according to claim 1 magnesium alloy strip blank; it is characterized in that described apparatus structure is also provided with melt protecting cover; described melt protecting cover covers on the storage bin of feeding device, is provided with air inlet pipe and feed pipe on melt protecting cover.
8. the device of the continuous semisolid casting of a kind of belt according to claim 7 magnesium alloy strip blank, is characterized in that described apparatus structure is also provided with leveling device, and described leveling device is arranged on the lower end of feed pipe.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410447981.4A CN104249136B (en) | 2014-09-04 | 2014-09-04 | The continuous semisolid casting of a kind of belt magnesium alloy strip blank device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410447981.4A CN104249136B (en) | 2014-09-04 | 2014-09-04 | The continuous semisolid casting of a kind of belt magnesium alloy strip blank device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104249136A CN104249136A (en) | 2014-12-31 |
| CN104249136B true CN104249136B (en) | 2016-05-18 |
Family
ID=52184588
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410447981.4A Active CN104249136B (en) | 2014-09-04 | 2014-09-04 | The continuous semisolid casting of a kind of belt magnesium alloy strip blank device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104249136B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2230638Y (en) * | 1995-06-23 | 1996-07-10 | 鞍山钢铁学院 | Crystallizer with adjustable walls and conicity for continuous casting machine |
| US5983981A (en) * | 1997-06-13 | 1999-11-16 | Ishikawajima-Harima Heavy Industries Company Ltd. | Casting steel strip |
| CN101314178B (en) * | 2007-05-28 | 2010-06-09 | 宝山钢铁股份有限公司 | Method for manufacturing gradient self-generating functional material by using double-roll thin-belt continuous casting |
| CN102398002A (en) * | 2011-11-24 | 2012-04-04 | 德阳宏广科技有限公司 | Steel belt wheel-type continuous casting machine for continuous casting of lead belts |
| JP2013006197A (en) * | 2011-06-24 | 2013-01-10 | Ihi Corp | Twin roll casting machine |
| CN204052831U (en) * | 2014-09-04 | 2014-12-31 | 内蒙古汇豪镁业有限公司 | A kind of belt continuous semisolid casting magnesium alloy strip blank device |
-
2014
- 2014-09-04 CN CN201410447981.4A patent/CN104249136B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2230638Y (en) * | 1995-06-23 | 1996-07-10 | 鞍山钢铁学院 | Crystallizer with adjustable walls and conicity for continuous casting machine |
| US5983981A (en) * | 1997-06-13 | 1999-11-16 | Ishikawajima-Harima Heavy Industries Company Ltd. | Casting steel strip |
| CN101314178B (en) * | 2007-05-28 | 2010-06-09 | 宝山钢铁股份有限公司 | Method for manufacturing gradient self-generating functional material by using double-roll thin-belt continuous casting |
| JP2013006197A (en) * | 2011-06-24 | 2013-01-10 | Ihi Corp | Twin roll casting machine |
| CN102398002A (en) * | 2011-11-24 | 2012-04-04 | 德阳宏广科技有限公司 | Steel belt wheel-type continuous casting machine for continuous casting of lead belts |
| CN204052831U (en) * | 2014-09-04 | 2014-12-31 | 内蒙古汇豪镁业有限公司 | A kind of belt continuous semisolid casting magnesium alloy strip blank device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104249136A (en) | 2014-12-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101678415B (en) | Process and plant for the production of metal strip | |
| CN101660063B (en) | Device for preparing semi-solid alloy melt and process for preparing AlSi9Mg semi-solid alloy | |
| CN110000355B (en) | Method for improving frame segregation of bloom continuous casting billet | |
| CN105728462B (en) | A kind of ultrasonic casting-rolling method of magnesium alloy slab | |
| KR101446993B1 (en) | Low surface roughness cast strip and method and apparatus for making the same | |
| CN201669392U (en) | Semi-solid casting-rolling double-roll type thin strip bloom conticaster | |
| US20150251244A1 (en) | Method and Device for Continuous Thin Strip Casting | |
| CN104399929A (en) | Method for reducing longitudinal division of weather-proof steel continuously cast slab | |
| CN108838207A (en) | Metal casting method for tandem rolling and equipment | |
| CN102896285B (en) | A kind of thin strap continuous casting casting method and device | |
| CN103406520B (en) | Device and method for producing large homogeneous electro-slag re-melting steel ingots added with consumable stirrer | |
| CN204052831U (en) | A kind of belt continuous semisolid casting magnesium alloy strip blank device | |
| CN113231611B (en) | Method for determining technological parameters of continuous casting steel strip feeding by low-superheat isothermal eutectic method | |
| CN103624224B (en) | Prepare the band extruder of battery grid. g., lead tape | |
| CN104841898A (en) | Method and device capable of producing multiple pieces of magnesium alloy cast sticks simultaneously | |
| CN106825461A (en) | The device and application method of a kind of crystal grain thinning tissue | |
| CN203508951U (en) | Wave taper-shaped centrifugal shearing and chilling device for preparing semi-solid state sizing agent | |
| CN104249136B (en) | The continuous semisolid casting of a kind of belt magnesium alloy strip blank device | |
| CN203044831U (en) | Novel high-strength water-cooling crystallizer | |
| CN201353635Y (en) | Round billet conticaster with extra large section | |
| KR100673618B1 (en) | Manufacturing apparatus for casting semi-solid materials and process method thereof | |
| CN204934550U (en) | A kind of casting apparatus | |
| CN205008546U (en) | Prepare casting device of high -quality aluminum alloy ingot casting in succession | |
| CN207592747U (en) | A kind of high-alloy steel integrated casting and rolling equipment | |
| CN106001469A (en) | Horizontal continuous casting crystallizer of cast iron and preparing method of cast iron proximate matter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |