TW202319142A - Aluminum alloy continuous casting apparatus accelerates cooling effect for aluminum casting blank through direct cooling device to improve crack phenomenon - Google Patents

Abstract

The invention relates to an aluminum alloy continuous casting apparatus comprising a crystallization device having crystallization roller. An inner cooling device and an outer cooling device are respectively disposed at an inner side and an outer side of the crystallization roller of the crystallization device, and a direct cooling device is configured at the external side of discharge port of the crystallization roller from the crystallization device to directly cool an aluminum casting blank flowing from the discharge port. The aluminum alloy continuous casting apparatus provides the inner cooling device and the outer cooling device to perform indirect cooling and carries out direct cooling through the direct cooling device so as to assist in accelerating the effect of cooling the aluminum casting blank to reduce crack phenomenon. Moreover, it does not reduce the rotation speed of the crystallization roller and thereby increase production speed.

Description

Aluminum alloy continuous casting equipment

This invention is an aluminum alloy continuous casting equipment, especially the aluminum alloy continuous casting equipment that can speed up the forming speed.

At present, the continuous casting and rolling process of aluminum alloy disc elements includes continuous casting process, continuous rolling process and coil coiling process. Among them, the aluminum alloy solution is added with alloy elements to remove filter and slag, and is refined and purified through the control of chemical composition. Stand in the holding furnace for processing, then pour into the crystallizer of the existing aluminum alloy continuous casting equipment, the poured aluminum soup enters the crystallizer through the sprue, the aluminum liquid slowly solidifies through the crystallizer, and the heat is taken away by the water cooling mechanism , as the temperature decreases, the thickness of the solidified shell gradually increases, and then through 180-degree rotation, the aluminum soup solidifies and forms an aluminum alloy wire, which is continuously pulled out from the crystallization wheel, and then enters the rolling machine for continuous rolling process, rolling The final aluminum alloy is then rolled up by the winding mechanism.

Among the above, the existing aluminum alloy continuous casting equipment provides an internal cooling device and an external cooling device, but both the internal cooling device and the external cooling device are indirect cooling, and the cooling effect is not good, causing the aluminum casting blank to leave the crystallization wheel. Complete cooling and solidification will cause the aluminum casting billet leaving the crystallization wheel to break. Therefore, the rotation speed of the crystallization wheel can only be reduced, but the production speed cannot be increased.

Taking 6056 aluminum alloy as an example, the zero ductility temperature (ZDT) of 6056 aluminum alloy is relatively low. If the rotation speed of the crystallization wheel is too fast, the aluminum casting blank has not completely solidified, so it will break when leaving the crystallization wheel. Therefore, the production speed cannot be increased.

Among them, zero strength temperature (zero strength temperature, ZST for short) means the temperature at which the metal just solidified at the solid-liquid interface begins to resist external force; zero plasticity temperature (ZDT) means the temperature at which the solidified metal begins to resist deformation; in ZST Between ZDT and ZDT, the material has a certain strength but has no ability to resist plastic deformation. It is a crack sensitive area. Only when the temperature drops to ZDT, the plasticity of the material will begin to increase sharply and increase the ability to resist deformation. Therefore, the lower ZDT and ZST , the higher the crack sensitivity.

The main purpose of this creation is to provide an aluminum alloy continuous casting equipment, so as to improve the problem that the existing aluminum alloy continuous casting equipment provides indirect cooling and the cooling effect is not good, and the problem that the production speed cannot be increased due to the reduction of the rotation speed of the crystallization wheel.

In order to achieve the purpose of the previous disclosure, the aluminum alloy continuous casting equipment of this creation includes: a crystallizer having a crystallization wheel; An internal cooling device, which is arranged inside the crystallization wheel of the crystallizer; An external cooling device, which is arranged on the outside of the crystallization wheel of the crystallizer; A direct cooling device, which is arranged outside the soup outlet of the crystallization wheel of the crystallizer, is used to directly cool the aluminum casting slab coming out of the soup outlet.

In addition to providing the internal cooling device and the external cooling device for indirect cooling, the aluminum alloy continuous casting equipment uses the direct cooling device for direct cooling of the aluminum billets coming out of the soup outlet, and the direct cooling device assists Accelerate the cooling effect of the aluminum casting blank, improve the cracking phenomenon, and do not need to reduce the rotation speed of the crystallization wheel, thereby increasing the production speed.

As shown in FIG. 1 , the aluminum alloy continuous casting equipment of the present invention includes a crystallizer 10 , an internal cooling device 20 , an external cooling device 30 and a direct cooling device 40 .

The crystallizer 10 includes a crystallization wheel 11, the crystallization wheel 11 has a soup inlet and a soup outlet, and the crystallizer 10 includes a tension wheel 12, the tension wheel 12 is spaced from the crystallization wheel 11, and a The steel belt 13 is wound around the tension wheel 12 and the crystallization wheel 11 arranged at intervals. As shown in FIG. Trapezoidal.

The internal cooling device 20 is disposed inside the crystallization wheel 11 of the crystallizer 10 ; the external cooling device 30 is disposed outside the crystallization wheel 11 of the crystallizer 10 .

The direct cooling device 40 is arranged on the outside of the soup outlet of the crystallization wheel 11 of the crystallizer 10, and is used to directly cool the aluminum casting blank 50 coming out of the soup outlet, wherein the direct cooling device 40 has a nozzle 41, The nozzle 41 faces the outer surface of the aluminum casting blank 50 coming out through the soup outlet, and the cooling fluid ejected from the nozzle 41 directly cools the aluminum casting blank 50 coming out through the soup outlet, and the direct cooling device 40 is a water cooling type The direct cooling device, and the cooling water temperature ranges from 10 to 35 degrees Celsius, which will be adjusted according to the weather conditions. As shown in Figure 2, the cooled aluminum casting blank 50 solidifies and forms an aluminum alloy wire, which is then pulled out by the crystallization wheel 11. Then enter the rolling machine 60 to carry out the continuous rolling process, and the rolled aluminum alloy is then rolled up by the rolling mechanism 70 .

Further establish the simulation model and technology of the manufacturing process, and explore the influence of parameters on the solidification and temperature distribution of the aluminum soup in the copper wheel mold. First, use SOLIDWORKS software to build the solid model of the copper wheel and steel strip, and then load the model into F1OW-3D commercial The packaged software, through grid segmentation design, aluminum soup material properties and process boundary condition parameters, establishes a heat flow numerical calculation model according to the finite difference method, and simulates and calculates the solidification state of aluminum soup under various process parameters.

6056 aluminum alloy was used for testing, the physical properties were set as shown in Table 1 below, and the solid-liquid phase temperature range was 100°C. Material 6056 aluminum alloy Density(kg/m3) 2712 Specific heat (J/kg℃) 885 Thermal conductivity (W/m℃) 164 Viscosity Coefficient(kg/ms) 0.00115 Latent heat (J/kg) 336000 Liquidus temperature (℃) 550 Solidus temperature (℃) 650 Table 1: Physical properties of 6065 aluminum alloy material

The process parameter conditions are shown in Table 2 below, the casting temperature is 700°C, and the casting speeds are 0.16m/s and 0.2m/s respectively. Casting speed (m/s) 0.16, 0.2 Output (ton/hour) 3.4, 4.2 Casting temperature (℃) 700 Heat transfer coefficient (W/m2℃) 2000~3000 Table 2: Process parameters

Example 1: The heat transfer coefficient of general metals is between 2000 and 3000. The steel strip 13 is divided into three equal parts to set different heat transfer coefficients, which are 3000W/m°C, 3000W/m°C and 2000W/m°C respectively , the heat transfer coefficient of the copper mold is fixed at 2000W/m°C, and the results of simulation analysis: when the casting speed is 0.2m/s, the outlet temperature can be close to 600°C, which has exceeded the zero plastic temperature of 6056, which will cause the material to have heat cracking occurs.

Embodiment 2: After adding the direct cooling device 40, except that the heat transfer coefficient of the steel strip 13 and the copper mold is fixed, add water to directly contact the heat transfer coefficient of the billet (the heat transfer coefficient of water is about 30000W/ m℃), the results of the simulation analysis: when the casting speed is 0.2m/s, the highest outlet temperature is 540℃, which is lower than the zero plastic temperature of 6056 aluminum alloy, so there will be no thermal cracking, so it can be It is known that adding the direct cooling device 40 can indeed reduce the temperature of the billet, ensure the quality of the billet and increase the productivity.

In summary, the aluminum alloy continuous casting equipment uses the internal cooling device and the external cooling device to indirectly cool the aluminum casting blank 50 in the crystallization wheel 11, and at the same time uses the direct cooling device to cool the aluminum castings coming out of the soup outlet. The embryo 50 is directly cooled, so that the temperature can be smoothly lowered to below the zero plasticity temperature, so as to improve the cracking phenomenon, improve the product yield, and increase the production speed without reducing the rotation speed of the crystallization wheel 11 .

10: Crystallizer 11:Crystal wheel 111: side board 12: tensioning wheel 13: Steel belt 20: Internal cooling device 30: External cooling device 40: Direct cooling device 41: Nozzle 50: aluminum casting blank 60:Rolling machine 70: retracting mechanism

Fig. 1: It is a schematic side view of one of the preferred embodiments of the aluminum alloy continuous casting equipment of the present invention. Figure 2: It is a schematic diagram of the use status of one of the preferred embodiments of the aluminum alloy continuous casting equipment of the present invention. Figure 3: A schematic cross-sectional view of the crystallization wheel of the aluminum alloy continuous casting equipment created by the present invention.

10: Crystallizer

11:Crystal wheel

12: tensioning wheel

13: Steel belt

20: Internal cooling device

30: External cooling device

40: Direct cooling device

41: Nozzle

50: aluminum casting blank

Claims (4)

A kind of aluminum alloy continuous casting equipment, it comprises: a crystallizer having a crystallization wheel; An internal cooling device, which is arranged inside the crystallization wheel of the crystallizer; An external cooling device, which is arranged on the outside of the crystallization wheel of the crystallizer; A direct cooling device, which is arranged outside the soup outlet of the crystallization wheel of the crystallizer, is used to directly cool the aluminum casting slab coming out of the soup outlet. The aluminum alloy continuous casting equipment as claimed in claim 1, wherein the direct cooling device has a nozzle, the nozzle faces the outer surface of the aluminum casting slab coming out of the soup outlet, and the cooling fluid sprayed from the nozzle directly passes through the The aluminum casting blanks coming out of the soup outlet are cooled. The aluminum alloy continuous casting equipment according to claim 1 or 2, wherein, the crystallizer includes a tensioning wheel, the tensioning wheel is spaced apart from the crystallization wheel, and a steel belt is wound around the spaced apart tensioning wheel Tight wheel with the crystallized wheel on the outside. The aluminum alloy continuous casting equipment as claimed in claim 1 or 2, wherein the direct cooling device is a water-cooled direct cooling device, and the cooling water temperature ranges from 10 to 35 degrees Celsius.

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