Method for measuring tail length of aluminum alloy sheet and application thereof

Abstract

The application discloses a method for measuring tail contraction length of an aluminum alloy plate and application thereof, and relates to the technical field of aluminum alloy extrusion detection. The aluminum alloy plate is obtained by extruding an aluminum alloy casting rod through a forward extrusion process. During the extrusion, the aluminum alloy casting rod flows through an extrusion cylinder and an extrusion die in sequence, the extrusion is stopped at the end of the extrusion, and an extrusion pressure residue is reserved in the extrusion cylinder. The method comprises the following steps: respectively measuring or obtaining the cross-section length and the cross-section width of the aluminum alloy plate, the length of the aluminum alloy casting rod, the cylinder diameter of the extrusion cylinder, the rod diameter of the aluminum alloy casting rod and the thickness of the extrusion pressure residue; and then calculating the tail contraction length. Based on the above method, a large amount of tail contraction length verification and batch inspection work can be avoided, the production process is simplified, manpower and material resources are saved, and high production efficiency is achieved in the plate extrusion production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aluminum alloy extrusion detection, and particularly relates to a method for measuring tail contraction length of aluminum alloy plate and application thereof. BACKGROUND

[0002] In the forward extrusion of aluminum alloy, tail contraction is a defect that enters the product interior due to the radial flow and circulation of the metal at the end of the extrusion, and the oxide, lubricant and dirt, bubbles, segregation nodules and other defects on the surface of the ingot enter the product interior, which has a certain rule to destroy the continuity and density of the product organization. In production, the solid material must be cut off the organizational defects. In the extrusion production, the extrusion test is needed, and the sample plate is cut section by section for low-power inspection, so as to determine the tail contraction length of the product, which consumes a lot of manpower and time. SUMMARY

[0003] The technical problem to be solved by the present application is to provide a method for measuring tail contraction length of aluminum alloy plate, which can quickly determine the tail contraction length of the aluminum alloy plate after extrusion, and lay a good foundation for subsequent processing.

[0004] In order to solve the above technical problem, the present application provides a method for measuring tail contraction length of aluminum alloy plate, the aluminum alloy plate is obtained by extruding an aluminum alloy ingot through a forward extrusion process, and the aluminum alloy ingot flows through an extrusion cylinder and an extrusion die in turn during extrusion, the extrusion is stopped at the end of the extrusion, and an extrusion pressure residue is retained in the extrusion cylinder; the measuring method comprises:

[0005] respectively measuring or obtaining the cross-sectional length and cross-sectional width of the aluminum alloy plate, the length of the aluminum alloy ingot, the cylinder diameter of the extrusion cylinder, the rod diameter of the aluminum alloy ingot and the thickness of the extrusion pressure residue;

[0006] the tail contraction length is calculated according to the following formula:

[0007]

[0008] wherein, l is the tail contraction length, L is the length of the aluminum alloy ingot, a is the cross-sectional length of the aluminum alloy plate, b is the cross-sectional width of the aluminum alloy plate, D is the rod diameter of the aluminum alloy ingot, D is the cylinder diameter of the extrusion cylinder, h is the thickness of the extrusion pressure residue, and K is a constant, the value range of which is 0.18-0.21.

[0009] As an improvement of the above technical solution, when the aluminum alloy ingot is 6063 aluminum alloy, K is 0.185;

[0010] When the aluminum alloy ingot is 6005 aluminum alloy, K is 0.188;

[0011] K is 0.195 when the aluminum alloy cast bar is 6061 aluminum alloy;

[0012] K is 0.205 when the aluminum alloy cast bar is 6082 aluminum alloy.

[0013] As an improvement of the above technical solution, the extrusion ratio of the aluminum alloy cast bar is calculated according to the following formula:

[0014]

[0015] Wherein, λ is the extrusion ratio, a is the cross-sectional length of the aluminum alloy plate, b is the cross-sectional width of the aluminum alloy plate, is the barrel diameter of the extrusion barrel;

[0016] The value range of λ is 10-80.

[0017] As an improvement of the above technical solution, the extrusion speed is 3-15 m / min.

[0018] As an improvement of the above technical solution, during extrusion, the temperature of the aluminum alloy cast bar is 480-520℃, and the temperature of the extrusion barrel is 430-470℃.

[0019] As an improvement of the above technical solution, the extrusion die comprises a die body and a die pad connected with the die body, the die body is provided with a flow guide hole, a die hole and a hollow cutter which are sequentially communicated, and the die pad is provided with a flow channel; the aluminum alloy cast bar sequentially flows through the flow guide hole, the die hole, the hollow cutter and the flow channel;

[0020] Wherein, the flow guide depth of the flow guide hole is 15-30 mm.

[0021] As an improvement of the above technical solution, the cross section of the flow guide hole is in a horn shape, and the included angle between the side wall and the extrusion direction is 8-15°.

[0022] As an improvement of the above technical solution, the inner side of the die hole is a working belt, and the length of the working belt is 3-15 mm.

[0023] As an improvement of the above technical solution, the hollow cutter comprises a first-stage hollow cutter arranged close to the die hole and a second-stage hollow cutter arranged close to the flow channel, and the diameter of the second-stage hollow cutter is greater than that of the first-stage hollow cutter.

[0024] The flow guide hole, the die hole, the first-stage hollow cutter, the second-stage hollow cutter and the flow channel are coaxially arranged.

[0025] Correspondingly, the application also discloses the application of the above-mentioned measuring method of the tail shrinkage length of the aluminum alloy plate in the following (1) or (2):

[0026] (1) aluminum alloy extrusion part post-processing;

[0027] (2) Aluminum alloy extrusion die design.

[0028] The present application has the following beneficial effects:

[0029] The method for measuring the tail contraction length of the aluminum alloy plate directly calculates the tail contraction length by the cross-sectional length and cross-sectional width of the aluminum alloy plate, the length of the aluminum alloy casting rod, the barrel diameter of the extrusion barrel, the rod diameter of the casting rod and the thickness of the extrusion pressure surplus: avoids a large amount of tail contraction length verification and batch inspection work, simplifies the production process, saves manpower and material resources, and has high production efficiency in plate extrusion production. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 is a structural schematic diagram of an extrusion die in an embodiment of the present application;

[0031] Figure 2 is a physical picture of the extruded plate sample after alkali etching in embodiment 1 of the present application;

[0032] Figure 3 is a physical picture of the extruded plate sample after alkali etching in embodiment 2 of the present application. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below with specific embodiments.

[0034] The present application discloses a method for measuring the tail contraction length of an aluminum alloy plate, specifically comprising measuring or obtaining the cross-sectional length and cross-sectional width of the aluminum alloy plate, the length of the aluminum alloy casting rod, the barrel diameter of the extrusion barrel, the rod diameter of the aluminum alloy casting rod and the thickness of the extrusion pressure surplus, respectively; and then calculating the tail contraction length according to the following formula:

[0035]

[0036] Wherein, l is the tail contraction length, L is the length of the aluminum alloy casting rod, a is the cross-sectional length of the aluminum alloy plate, b is the cross-sectional width of the aluminum alloy plate, D is the rod diameter of the aluminum alloy casting rod, D is the barrel diameter of the extrusion barrel, h is the thickness of the extrusion pressure surplus, and K is a constant, with a value range of 0.18-0.21.

[0037] The aluminum alloy plate is obtained by extruding an aluminum alloy cast bar through a forward extrusion process. During the extrusion, the aluminum alloy cast bar flows through an extrusion cylinder and an extrusion die in sequence, the extrusion is stopped at the end of the extrusion, and an extrusion pressure residue is retained in the extrusion cylinder. It should be noted that a certain amount of aluminum alloy is retained in the extrusion die and the extrusion cylinder after the extrusion is stopped, and the part retained in the extrusion cylinder is the extrusion pressure residue. The extrusion cylinder retreats after the subsequent extrusion, the extrusion pressure residue is removed from the extrusion cylinder, and the extrusion pressure residue is actively sheared between the extrusion cylinder and the extrusion die through a shearing device, so as to remove the extrusion pressure residue. After the extrusion pressure residue is removed, a new aluminum alloy cast bar is loaded for the next round of extrusion. That is, the stoppage of the extrusion in the present application does not mean complete stoppage of the extrusion, but refers to the stage of the stoppage of the extrusion process in the middle of the extrusion of different aluminum alloy cast bars.

[0038] The determination method of the present application can be applied to the extruded plate based on the forward extrusion process.

[0039] Specifically, when the aluminum alloy cast bar is 6063 aluminum alloy, K is 0.185; when the aluminum alloy cast bar is 6005 aluminum alloy, K is 0.188; when the aluminum alloy cast bar is 6061 aluminum alloy, K is 0.195; and when the aluminum alloy cast bar is 6082 aluminum alloy, K is 0.205. By controlling the value of K, the influence of the material of the aluminum alloy plate on the tail contraction length can be considered, and the accuracy of the determination can be improved. Specifically, in order to more accurately determine the tail contraction length of the aluminum alloy plate, the specific process parameters during the extrusion need to be controlled. Specifically, the extrusion ratio is controlled to be 10-80, the extrusion speed is controlled to be 3-15 m / min, the temperature of the aluminum alloy cast bar is controlled to be 480-520℃, and the temperature of the extrusion cylinder is controlled to be 430-470℃. The extrusion ratio is calculated according to the following formula:

[0040]

[0041] wherein λ is the extrusion ratio, a is the cross-sectional length of the aluminum alloy plate, b is the cross-sectional width of the aluminum alloy plate, is the diameter of the extrusion cylinder.

[0042] Specifically, the determination method of the present application can be applied to various types of plate molds, such as the flat mold commonly used in the art. Preferably, in one embodiment of the present application, referring to Figure 1 , the extrusion die comprises a die body 1 and a die cushion 2 connected to the die body 1, the die body 1 is provided with a flow guide hole 11, a die hole 12 and a blanking hole 13 which are communicated in sequence, and the die cushion 2 is provided with a flow channel 21; the aluminum alloy cast bar flows through the flow guide hole 11, the die hole 12, the blanking hole 13 and the flow channel 21 in sequence.

[0043] The depth L of the flow guide hole 11 is 15-30 mm, the shallow flow guide hole 11 can avoid too much aluminum storage in the feeding port, cause long head-tail material transverse welding (defect of organization, also called "delamination") in the head of the extruded product, reduce the length of the head waste, concentrate the process waste in the tail end, improve the accuracy of the calculation of the tail end length, and make the subsequent processing (saw cutting removal, etc.) simpler. Preferably, in one embodiment of the application, the cross section of the flow guide hole 11 is trumpet-shaped, that is, the diameter gradually increases from the feeding end to the end close to the die hole 12, and the angle α between the side wall and the extrusion direction is 8-15°. The flow guide hole 11 with this shape has the effect of storing aluminum and preventing shearing. When the extrusion is stopped and the extrusion pressure shearing is carried out, the aluminum alloy embedded in the flow guide has a certain adhesion resistance, which avoids shearing the aluminum storage in the die flow guide hole when shearing the extrusion pressure, ensures the accuracy of the subsequent extrusion pressure thickness measurement, and further improves the accuracy of the tail end length measurement, and facilitates the subsequent continuous extrusion.

[0044] The die hole 12 is straight and the inner side is a working belt 12a. The length of the working belt 12a is 3-15 mm.

[0045] The die hole 12 is straight and the inner side is a working belt 12a. The length of the working belt 12a is 3-15 mm.

[0046] Based on the above-mentioned tail end length measurement method of the application, the tail end length can be quickly and accurately determined. The data basis is provided for aluminum alloy extrusion and post-processing, for example, after the tail end length is determined, a saw cutting device can be directly added at the extrusion outlet to cut off the tail end part, realizing the standardization and standardization management from the production source. For example, the tail end length of the new extrusion die can be quickly evaluated according to the measurement method, and then data basis is provided for the design improvement of the extrusion die.

[0047] Correspondingly, the application also discloses an aluminum alloy billet extrusion method, which comprises the following steps:

[0048] S1: preheat the aluminum alloy billet and the extrusion cylinder;

[0049] Specifically, the aluminum alloy billet is preheated to 480-520 DEG C, and the extrusion cylinder is preheated to 430-470 DEG C.

[0050] S2: extrude the preheated aluminum alloy billet, and the aluminum alloy billet flows through the extrusion cylinder and the extrusion die in sequence during extrusion to obtain an aluminum alloy plate blank;

[0051] The extrusion die is the same as above. The extrusion ratio is 10-80, and the extrusion speed is 3-15 m / min.

[0052] S3: quenching the aluminum alloy plate blank;

[0053] S4: sawing the quenched plate blank to remove the tail portion of the tail, thereby obtaining an aluminum alloy plate product.

[0054] Specifically, the length of the tail portion is calculated according to the following formula:

[0055]

[0056] wherein l is the tail length, L is the length of the aluminum alloy cast bar, a is the cross-sectional length of the aluminum alloy plate, b is the cross-sectional width of the aluminum alloy plate, D is the bar diameter of the aluminum alloy cast bar, is the barrel diameter of the extrusion barrel, h is the thickness of the extrusion pressure, and K is a constant, which is in the range of 0.18-0.21.

[0057] The application will be further described in specific embodiments as follows:

[0058] Example 1

[0059] This embodiment provides a method for measuring the tail length of an aluminum alloy plate. Specifically, the aluminum alloy plate is made of 6063 aluminum alloy and is obtained by forward extrusion of an aluminum alloy cast bar. The die structure used in the extrusion is shown in Figure 1 Specifically, the extrusion die includes a die body 1 and a die pad 2 connected to the die body 1. The die body 1 is provided with a flow guide hole 11, a die hole 12, a first air knife 13a and a second air knife 13b connected in sequence, and the die pad 2 is provided with a flow channel 21. The flow hole 11, the die hole 12, the first air knife 13a, the second air knife 13b and the flow channel 21 are coaxially arranged. The flow guide hole 11 is in the shape of a horn, the flow guide depth L is 20 mm, and the angle between the side wall and the extrusion direction is 10°. The die hole 12 is in the shape of a straight cylinder, and the inner side is a working belt 12a. The length of the working belt 12a is 5-11 mm.

[0060] The extrusion process conditions are as follows: the extrusion speed is 9 m / min, the temperature of the aluminum alloy cast bar is 490℃, the temperature of the extrusion barrel is 440℃, and the extrusion ratio is 40.71.

[0061] The cross-sectional length of the aluminum alloy plate obtained after extrusion is 29 mm, and the cross-sectional width is 23 mm. The barrel diameter of the extrusion barrel is 186 mm, the bar diameter of the aluminum alloy cast bar is 178 mm, and the length is 920 mm. The thickness of the extrusion pressure is 30 mm.

[0062] The tail length is:

[0063]

[0064] The tail 7m, 6.5m, 6m, 5.5m, 5m, 4.5m, 4m, 3.5m, 3m, 2.5m, 2m, 1.5m, 1m, 0.5m of the sample plate are cut respectively for alkali washing, and the actual figure after alkali washing is shown in Figure 2 The figure from left to right is 7m, 6.5m, 6m, 5.5m, 5m, 4.5m, 4m, 3.5m, 3m, 2.5m, 2m, 1.5m, 1m, 0.5m. It can be seen from the figure that the low magnification tissue of the 5th meter shows tail contraction, and the 5.5th meter shows no tail contraction, and the tail contraction length is greater than 5 meters and less than 5.5 meters, which is consistent with the calculated value.

[0065] Example 2

[0066] The present embodiment provides a method for measuring the tail contraction length of an aluminum alloy plate. Specifically, the material of the aluminum alloy plate is 6063 aluminum alloy, which is obtained by forward extrusion process of aluminum alloy cast bar. The mold structure used in the extrusion is shown in Figure 1 Specifically, the extrusion mold includes a mold body 1 and a mold pad 2 connected to the mold body 1. The mold body 1 is provided with a flow guide hole 11, a mold hole 12, a first air knife 13a and a second air knife 13b which are communicated in sequence, and the mold pad 2 is provided with a flow channel 21. The flow guide hole 11, the mold hole 12, the first air knife 13a, the second air knife 13b and the flow channel 21 are coaxially arranged. The flow guide hole 11 is in the shape of a horn, the depth L of the flow guide hole is 20mm, and the angle between the side wall of the flow guide hole and the extrusion direction is 10°. The mold hole 12 is in the shape of a straight cylinder, and the inner side surface is a working belt 12a. The length of the working belt 12a is 3-5mm.

[0067] The extrusion process conditions are as follows: the extrusion speed is 7m / min, the temperature of the aluminum alloy cast bar is 490℃, the temperature of the extrusion cylinder is 445℃, and the extrusion ratio is 57.05.

[0068] The cross-sectional length of the aluminum alloy plate obtained after extrusion is 68mm, and the cross-sectional width is 7mm. The cylinder diameter of the extrusion cylinder is 186mm, the bar diameter of the aluminum alloy cast bar is 178mm, and the length is 560mm. The thickness of the extrusion pressure is 25mm.

[0069] The tail contraction length is:

[0070]

[0071] The tail 5m, 4.5m, 4m, 3.5m, 3m, 2.5m, 2m, 1.5m, 1m, 0.5m of the sample plate are cut respectively for alkali washing, and the actual figure after alkali washing is shown in Figure 3The results are shown in the figure. From top to bottom, the figure shows 5 m, 4.5 m, 4 m, 3.5 m, 3 m, 2.5 m, 2 m, 1.5 m, 1 m, and 0.5 m. As can be seen from the figure, the 4 m low magnification tissue shows slight tail contraction, and the 4.5 m low magnification tissue shows no tail contraction, so the tail contraction length is greater than 4 m and less than 4.5 m, which is consistent with the calculated value.

[0072] The above describes the preferred embodiments of the application. It should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the application, and these improvements and refinements are also considered within the protection scope of the application.

Claims

1. A method for determining the tail length of an aluminum alloy sheet, wherein the aluminum alloy sheet is obtained by extruding an aluminum alloy cast rod through a forward extrusion process, wherein during extrusion, the aluminum alloy cast rod flows sequentially through an extrusion cylinder and an extrusion die, and extrusion is stopped at the end of the extrusion process, leaving an extrusion residue in the extrusion cylinder; characterized in that... The determination method includes: The cross-sectional length and width of the aluminum alloy sheet, the length of the aluminum alloy casting rod, the diameter of the extrusion cylinder, the diameter of the aluminum alloy casting rod, and the thickness of the extrusion residue are measured or obtained respectively. Calculate the length of the shortened tail using the following formula: Where l is the tail length, L is the length of the aluminum alloy cast rod, a is the cross-sectional length of the aluminum alloy sheet, b is the cross-sectional width of the aluminum alloy sheet, D is the diameter of the aluminum alloy cast rod, φ is the diameter of the extrusion cylinder, h is the thickness of the extrusion residue, and K is a constant with a value range of 0.18 to 0.

21.

2. The method for determining the tail length of aluminum alloy sheet as described in claim 1, characterized in that, When the aluminum alloy casting rod is 6063 aluminum alloy, K is 0.185; When the aluminum alloy casting rod is made of 6005 aluminum alloy, K is 0.188; When the aluminum alloy casting rod is 6061 aluminum alloy, K is 0.195; When the aluminum alloy casting rod is made of 6082 aluminum alloy, K is 0.

205.

3. The method for determining the tail length of aluminum alloy sheet as described in claim 1, characterized in that, The extrusion ratio of the aluminum alloy cast rod is calculated according to the following formula: Where λ is the extrusion ratio, a is the cross-sectional length of the aluminum alloy sheet, b is the cross-sectional width of the aluminum alloy sheet, and φ is the diameter of the extrusion cylinder. The value of λ ranges from 10 to 80.

4. The method for determining the tail length of aluminum alloy sheet as described in claim 1, characterized in that, The extrusion speed is 3~15m / min.

5. The method for determining the tail length of aluminum alloy sheet as described in claim 1, characterized in that, During extrusion, the temperature of the aluminum alloy cast rod is 480~520℃, and the temperature of the extrusion cylinder is 430~470℃.

6. The method for determining the tail length of aluminum alloy sheet as described in claim 1, characterized in that, The extrusion die includes a die body and a die pad connected to the die body. The die body is provided with a flow guide hole, a die hole and a blanking tool connected in sequence. The die pad is provided with a flow channel. The aluminum alloy cast rod flows through the flow guide hole, the die hole, the blanking tool and the flow channel in sequence. The flow depth of the guide hole is 15~30mm.

7. The method for determining the tail length of aluminum alloy sheet as described in claim 6, characterized in that, The cross-section of the guide hole is funnel-shaped, and the angle between its sidewall and the extrusion direction is 8~15°.

8. The method for determining the tail length of aluminum alloy sheet as described in claim 6, characterized in that, The inner surface of the die hole is a working strip, and the length of the working strip is 3~15mm.

9. The method for determining the tail length of aluminum alloy sheet as described in claim 6, characterized in that, The air cutter includes a primary air cutter located near the die hole and a secondary air cutter located near the flow channel, wherein the diameter of the secondary air cutter is larger than the diameter of the primary air cutter; The guide hole, die hole, primary air cutter, secondary air cutter, and flow channel are arranged coaxially.

10. The method for determining the tail length of aluminum alloy sheet as described in any one of claims 1 to 9, in the following (1) or (2): (1) Post-processing of aluminum alloy extrusions; (2) Design of aluminum alloy extrusion die.

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