Aluminum-magnesium alloy die-casting method for automobile parts

Abstract

The invention relates to an aluminum-magnesium alloy die-casting method for automobile parts applied in the field of die-casting technology. Before injecting material into a mold cavity, a circulating water circuit used for cooling is first detected. By using an external temperature comparison module and an internal temperature comparison module in coordination, the difference between the temperature difference of an inlet and outlet liquid and the standard temperature difference of a control group, as well as the difference between the internal and external temperature difference at each inflection point of the circulating water circuit and the standard temperature difference can be timely understood, so as to timely understand the actual situation of the circulating water circuit, effectively ensure that its heat exchange efficiency is in a normal state, effectively avoid the decrease of heat transfer efficiency due to scaling or other situations, and make the cooling speed of a target casting worse, thereby effectively ensuring the die-casting efficiency of the casting and the quality of the finished product.

Description

Technical Field

[0001] The invention relates to an aluminum-magnesium alloy die-casting method, in particular to an aluminum-magnesium alloy die-casting method for automobile parts applied in the field of die-casting technology. Background Art

[0002] Die casting is similar to injection molding, both of which involve injecting molten material into a mold, solidifying it after cooling, and demolding it to obtain the target product. The only difference is that injection molding produces plastic parts, while die casting generally produces metal parts.

[0003] The die-casting mold is generally provided with a circulating cooling system, which dissipates heat through the medium circulating in it. The scale generated on the tube wall of the heat exchanger (water cooler, condenser, etc.) in the circulating cooling water system will hinder the heat transfer of the heat exchanger and reduce the cooling effect; the scale generated in the pipeline for conveying cooling water will reduce the cross-sectional area of ​​the pipeline, reduce the flow rate of cooling water, and even block the channel of cold cooling water, reduce the cooling efficiency, and thus affect the overall production efficiency of the cooled die-casting. Summary of the invention

[0004] In view of the above-mentioned prior art, the technical problem to be solved by the present invention is that scaling in the circulating water channel affects the production efficiency of die castings.

[0005] In order to solve the above problems, the present invention provides a method for die-casting aluminum-magnesium alloy for automobile parts, comprising the following steps:

[0006] S1. Design a corresponding die-casting mold according to the target casting, the die-casting mold includes an upper mold and a lower mold, and the upper mold and the lower mold are combined to form a mold cavity, and a circulating water channel is arranged in the upper mold and the lower mold, and the circulating water channel is arranged around the mold cavity;

[0007] S2. Firstly, the circulating water circuit for cooling the die casting die is inspected, and then the die is preheated through the circulating water circuit;

[0008] The external temperature module and the internal temperature module are installed on the circulating water circuit. The specific steps for testing the circulating water circuit are as follows:

[0009] S21. First, an unused mold is used as a control group. Cooling water is introduced into the water inlet of the circulating water circuit in the control group at a fixed speed and discharged from the water outlet. The temperature difference between the inlet and outlet water of the circulating water circuit is compared by an external temperature comparison module. The temperature difference between the inside and outside of the circulating water circuit at each inflection point is recorded by an internal temperature comparison module.

[0010] S22, repeat the above steps, compare the temperature difference of the water inlet and outlet of the die-casting mold and the temperature difference at each inflection point with the temperature difference data of the control group, when the temperature difference data of the corresponding parts differ too much, it indicates that there is a problem with the heat exchange efficiency of the circulating water circuit, otherwise the heat exchange efficiency is normal;

[0011] S3, putting the aluminum-magnesium alloy material into a furnace for high-temperature melting, and injecting the molten aluminum-magnesium alloy material into a mold cavity that has been preheated;

[0012] S4. The molten aluminum-magnesium alloy material is solidified and then cooled, and then demolded to obtain a target casting.

[0013] In the above-mentioned aluminum-magnesium alloy die-casting method for automotive parts, the circulating water circuit used for cooling is first inspected before injecting material into the mold cavity to effectively ensure that its heat exchange efficiency is in a normal state, effectively avoid the decrease in heat transfer efficiency due to scaling or other conditions, and cause the cooling rate of the target casting to deteriorate, thereby effectively ensuring the die-casting efficiency of the casting and the quality of the finished product.

[0014] As a further improvement of the present application, when testing the temperature difference at each point of the circulating water circuit to be tested, the water entry speed, water entry temperature and test time nodes are kept consistent with those of the control group.

[0015] As a further improvement of the present application, the circulating water circuit includes a plurality of rectangular tubes and an offset inclined tube fixedly connected to the end of the rectangular tube on the water outlet side. The end of the rectangular tube on the water inlet side and the end of the offset inclined tube are respectively fixedly connected with an inlet pipe and a discharge pipe. The inlet pipe and the discharge pipe are fixedly extended to the outside of the movable mold or the fixed mold. External temperature sensors are installed at the mouths of the inlet pipe and the discharge pipe. The two external temperature sensors constitute an external temperature comparison module.

[0016] As a further improvement of the present application, the offset inclined tube is arranged obliquely, and the end of the rectangular tube on the water inlet side and the end of the offset inclined tube on the water outlet side are staggered and crossed with each other.

[0017] As a further improvement of the present application, an expanded diameter elbow is fixedly connected at each inflection point of the rectangular tube, the inner side of the expanded diameter elbow protrudes toward one side of the mold cavity, and internal temperature sensors are installed on the inner and outer walls of the protruding part of the expanded diameter elbow.

[0018] As a further improvement of the present application, the expanded diameter elbow and two internal temperature sensors constitute an internal temperature specific module, and the spatial cross-section in the middle of the expanded diameter elbow is 2-5 times the cross-section of the rectangular tube.

[0019] As another improvement of the present application, a scale connection detection module is also installed at the expanded diameter bend, and the scale connection detection module includes a scale connection strip fixedly connected to the inner wall of the expanded diameter bend away from the mold cavity, a tension sensor is installed between the middle part of the scale connection strip and the inner wall of the expanded diameter bend, a pull rope is fixedly connected between the tension sensor and the middle part of the scale connection strip, and an electromagnetic sheet is electrically connected to the protruding outer wall of the expanded diameter bend.

[0020] As another improved supplement of the present application, the scale connecting strip includes two positioning plates respectively fixed to the inner walls on both sides of the expanded diameter elbow, and a magnetic patch fixedly connected between the two positioning plates. The magnetic patch is provided with a plurality of evenly distributed bottom holes. The magnetic patch is an elastic structure, and the magnetic patch and the inner wall of the expanded diameter elbow are attached to each other.

[0021] In summary, before injecting material into the mold cavity, the circulating water circuit used for cooling is first tested. Through the coordinated use of the external temperature ratio module and the internal temperature ratio module, the difference between the inlet and outlet liquid temperature difference and the standard temperature difference of the control group, as well as the difference between the internal and external temperature difference at each inflection point of the circulating water circuit and the standard temperature difference can be timely understood, so as to timely understand the actual situation of the circulating water circuit, effectively ensure that its heat exchange efficiency is in a normal state, effectively avoid the decrease in heat transfer efficiency due to scaling or other conditions, and cause the cooling speed of the target casting to deteriorate, thereby effectively ensuring the die-casting efficiency of the casting and the quality of the finished product. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a main flow chart of the first implementation method of the present application;

[0023] Figure 2 A schematic diagram of a die-casting mold according to a first embodiment of the present application;

[0024] Figure 3 This is a main perspective schematic diagram of the upper mold of the first embodiment of the present application;

[0025] Figure 4 This is a three-dimensional diagram of a circulating water circuit according to a first embodiment of the present application;

[0026] Figure 5 This is a front view of the circulating water circuit after the internal temperature module is installed in the first embodiment of the present application;

[0027] Figure 6 This is a block diagram of the main detection principle of the circulating water circuit in the first embodiment of the present application;

[0028] Figure 7 This is a schematic diagram of a fouling detection module according to a second embodiment of the present application;

[0029] Figure 8 This is a schematic diagram of a scale connecting strip according to a second embodiment of the present application;

[0030] Fig. 9 This is a schematic diagram of the scale detection module directly detecting scale in the second embodiment of the present application;

[0031] Fig.10 This is a schematic diagram of the surface of the scale strip connected to the inner wall of the expanded diameter elbow after scaling in the second embodiment of the present application.

[0032] Description of the numbers in the figure:

[0033] 101 liquid inlet pipe, 102 liquid discharge pipe, 11 rectangular pipe, 12 offset inclined pipe, 13 expanded curved pipe, 21 external temperature sensor, 22 internal temperature sensor, 3 electromagnetic sheets, 4 scale strips, 41 positioning sheets, 42 magnetic patch, 401 bottom hole, 5 tension sensor, 6 pull rope. DETAILED DESCRIPTION

[0034] Two implementation modes of the present application are described in detail below with reference to the accompanying drawings.

[0035] The first implementation method:

[0036] Figure 1-2 A method for die-casting aluminum-magnesium alloy for automobile parts is shown, in which a represents an upper die, b represents a lower die, and c represents a furnace, comprising the following steps:

[0037] S1. Design a corresponding die-casting mold according to the target casting, the die-casting mold includes an upper mold and a lower mold, and the upper mold and the lower mold are combined to form a mold cavity, and a circulating water channel is arranged in the upper mold and the lower mold, and the circulating water channel is arranged around the mold cavity;

[0038] S2. Firstly, the circulating water circuit for cooling the die casting die is inspected, and then the die is preheated through the circulating water circuit;

[0039] The external temperature module and the internal temperature module are installed on the circulating water circuit. The specific steps for testing the circulating water circuit are as follows:

[0040] S21. First, an unused mold is used as a control group. Cooling water is introduced into the water inlet of the circulating water circuit in the control group at a fixed speed and discharged from the water outlet. The temperature difference between the inlet and outlet water of the circulating water circuit is compared by an external temperature comparison module. The temperature difference between the inside and outside of the circulating water circuit at each inflection point is recorded by an internal temperature comparison module.

[0041] S22, repeat the above steps, compare the temperature difference of the water inlet and outlet of the die-casting mold and the temperature difference at each inflection point with the temperature difference data of the control group, when the temperature difference data of the corresponding parts differ too much, it indicates that there is a problem with the heat exchange efficiency of the circulating water circuit, otherwise the heat exchange efficiency is normal;

[0042] S3, putting the aluminum-magnesium alloy material into a furnace for high-temperature melting, and injecting the molten aluminum-magnesium alloy material into a mold cavity that has been preheated;

[0043] S4. The molten aluminum-magnesium alloy material is solidified and then cooled, and then demolded to obtain a target casting.

[0044] When testing the temperature difference at each point of the circulating water circuit to be tested, the water inlet speed, water inlet temperature and test time node are kept consistent with those of the control group, effectively ensuring that the test effect of the heat exchange efficiency of the circulating water circuit is more accurate and effectively reducing errors.

[0045] like Figure 3-4 The circulating water circuit includes a plurality of rectangular tubes 11 and an offset inclined tube 12 fixedly connected to the end of the rectangular tube 11 on the water outlet side. The end of the rectangular tube 11 on the water inlet side and the end of the offset inclined tube 12 are respectively fixedly connected with an inlet pipe 101 and a discharge pipe 102. The inlet pipe 101 and the discharge pipe 102 are fixedly extended to the outside of the movable mold or the fixed mold. The mouths of the inlet pipe 101 and the discharge pipe 102 are both installed with external temperature sensors 21. The two external temperature sensors 21 form an external temperature ratio module. The offset inclined tube 12 is tilted, and the end of the rectangular tube 11 on the water inlet side and the end of the offset inclined tube 12 on the water outlet side are staggered and crossed with each other, so that there is no obvious blank area at the water inlet and water outlet positions of the circulating water circuit, which effectively avoids the situation where the temperature is too high due to the local lack of cooling.

[0046] like Figure 5 , an expanded elbow 13 is fixedly connected to each inflection point of the rectangular tube 11, the inner side of the expanded elbow 13 protrudes toward one side of the mold cavity, and the inner and outer walls of the protrusion of the expanded elbow 13 are installed with internal temperature sensors 22, the expanded elbow 13 and the two internal temperature sensors 22 form an internal temperature comparison module, and the setting of multiple internal temperature comparison modules can be used for the temperature difference inside and outside the corner of the circulating water channel. According to the size of the temperature difference data, it can be effectively judged whether scale is formed at the place, whether the scale is large and affects the heat exchange efficiency, so that the staff can carry out corresponding cleaning and maintenance in time, and reduce the impact on the quality of the die-casting and the die-casting efficiency. The spatial cross-section in the middle of the expanded elbow 13 is 2-5 times the cross-section of the rectangular tube 11. Since the corners of the pipeline are prone to scale, the larger cross-section can effectively reduce the impact of the reduced water flow due to scale on the heat exchange efficiency of the circulating water channel.

[0047] In summary, the circulating water circuit used for cooling should be tested before injecting material into the mold cavity. Through the coordinated use of the external temperature comparison module and the internal temperature comparison module, the difference between the inlet and outlet liquid temperature difference and the standard temperature difference of the control group, as well as the difference between the internal and external temperature difference and the standard temperature difference at each inflection point of the circulating water circuit can be timely understood, so as to timely understand the actual situation of the circulating water circuit and effectively ensure that its heat exchange efficiency is in a normal state, effectively avoid the decrease in heat transfer efficiency due to scaling or other conditions, and cause the cooling speed of the target casting to deteriorate, thereby effectively ensuring the die-casting efficiency of the casting and the quality of the finished product.

[0048] The second implementation method:

[0049] This embodiment is based on the first embodiment, and a scale detection module is added, and the rest of the parts are consistent with the first embodiment.

[0050] like Figure 7 and Fig. 9 A scale detection module is also installed at the expanded diameter elbow 13, and the scale detection module includes a scale strip 4 fixedly connected to the inner wall of the expanded diameter elbow 13 away from the mold cavity, a tension sensor 5 is installed between the middle of the scale strip 4 and the inner wall of the expanded diameter elbow 13, and a pull rope 6 is fixedly connected between the tension sensor 5 and the middle of the scale strip 4. The protruding outer wall of the expanded diameter elbow 13 is electrically connected to an electromagnetic sheet 3. After the internal and external temperatures at the inflection point are detected by the internal temperature comparison module, when there is a significant difference between the temperature difference at the inflection point and the standard temperature difference, the scale detection module is continued to be used for scale detection, thereby improving the accuracy of the detection result of whether scale is formed. The mold control center directly controls the electromagnetic The sheet 3 is energized to generate an adsorption force on the scale strip 4, causing it to deform toward the electromagnetic sheet 3 and then generate a pulling force on the tension sensor 5. In the absence of scaling, the tension data received by the tension sensor 5 is relatively large, and after scaling, the scale will generate a reverse resistance to the deformation of the scale strip 4, causing the tension data generated on the tension sensor 5 to become smaller accordingly. During each detection, it is possible to effectively determine whether scaling has occurred based on the tension data on the tension sensor 5, which is convenient for the staff to perform scale removal in a timely manner, thereby effectively ensuring efficient and uniform cooling during die-casting, which can not only effectively ensure the die-casting efficiency, but also reduce the impact on the quality of the finished die-casting parts.

[0051] like Fig. 9 The scale strip 4 includes two positioning pieces 41 respectively fixed to the inner walls of the two sides of the expanded diameter elbow 13, and a magnetic patch 42 fixedly connected between the two positioning pieces 41. The magnetic patch 42 is provided with a plurality of evenly distributed through-holes 401. The magnetic patch 42 is an elastic structure, and the magnetic patch 42 is attached to the inner wall of the expanded diameter elbow 13. After the circulating water circuit performs circulating cooling for a long time, scale will condense on the inner wall of the rectangular tube 11 and the expanded diameter elbow 13, especially at the corner of the expanded diameter elbow 13, where more scale condenses, such as Fig.10 Due to the arrangement of multiple through-holes 401, scale will form on the inner wall of the expanded bend 13 and on the surface of the magnetic patch 42, making the scale resemble a connector. The magnetic patch 42 and the expanded bend 13 can be temporarily fixed and limited. At this time, during detection, a greater resistance can be generated, so that under the same force of the electromagnetic sheet 3, the force data formed at the tension sensor 5 will become smaller, thereby achieving the effect of judging whether scale has formed according to the change in data.

[0052] In view of current practical needs, the above-mentioned implementation mode adopted in this application is not limited to the scope of protection. Various changes made within the knowledge scope of technical personnel in this field without departing from the concept of this application still fall within the scope of protection of the present invention.

Claims

1. A method for die-casting aluminum-magnesium alloy for automobile parts, characterized in that: The following steps are involved: S1. Design a corresponding die-casting mold according to the target casting, wherein the die-casting mold includes an upper mold and a lower mold, and the upper mold and the lower mold are combined to form a mold cavity, and a circulating water circuit is arranged in the upper mold and the lower mold, and the circulating water circuit is arranged around the mold cavity; S2. Firstly, the circulating water circuit for cooling the die casting die is inspected, and then the die is preheated through the circulating water circuit; The circulating water circuit is equipped with an external temperature comparison module and an internal temperature comparison module. The specific steps for testing the circulating water circuit are as follows: S21. First, an unused mold is used as a control group. Cooling water is introduced into the water inlet of the circulating water circuit in the control group at a fixed speed and discharged from the water outlet. The temperature difference between the inlet and outlet water of the circulating water circuit is compared by an external temperature comparison module. The temperature difference between the inside and outside of the circulating water circuit at each inflection point is recorded by an internal temperature comparison module. S22, repeat the above steps, compare the temperature difference of the water inlet and outlet of the die-casting mold and the temperature difference at each inflection point with the temperature difference data of the control group, when the temperature difference data of the corresponding parts differ too much, it indicates that there is a problem with the heat exchange efficiency of the circulating water circuit, otherwise the heat exchange efficiency is normal; S3, putting the aluminum-magnesium alloy material into a furnace for high-temperature melting, and injecting the molten aluminum-magnesium alloy material into a mold cavity that has been preheated; S4, cooling the molten aluminum-magnesium alloy material after solidification, and then demolding it to obtain a target casting; The circulating water circuit comprises a plurality of rectangular tubes (11) and offset inclined tubes (12) fixedly connected to the ends of the rectangular tubes (11) on the water outlet side; the ends of the rectangular tubes (11) on the water inlet side and the ends of the offset inclined tubes (12) are respectively fixedly connected to a liquid inlet pipe (101) and a liquid discharge pipe (102); the liquid inlet pipe (101) and the liquid discharge pipe (102) are fixedly extended to the outside of the movable mold or the fixed mold; the mouths of the liquid inlet pipe (101) and the liquid discharge pipe (102) are both installed with external temperature sensors (21); the two external temperature sensors (21) form an external temperature specific module; An expanded diameter elbow (13) is fixedly connected to each inflection point of the rectangular tube (11), the inner side of the expanded diameter elbow (13) protrudes toward one side of the mold cavity, and internal temperature sensors (22) are installed on the inner and outer walls of the protruding part of the expanded diameter elbow (13); A scale connection detection module is also installed at the expanded diameter bend (13), the scale connection detection module comprising a scale connection strip (4) fixedly connected to the inner wall of the expanded diameter bend (13) away from the mold cavity, a tension sensor (5) is installed between the middle of the scale connection strip (4) and the inner wall of the expanded diameter bend (13), a pull rope (6) is fixedly connected between the tension sensor (5) and the middle of the scale connection strip (4), an electromagnetic sheet (3) is electrically connected to the protruding outer wall of the expanded diameter bend (13), the scale connection strip (4) comprises two positioning sheets (41) respectively fixed to the inner walls of both sides of the expanded diameter bend (13), and a magnetic patch (42) fixedly connected between the two positioning sheets (41), a plurality of evenly distributed through-holes (401) are drilled on the magnetic patch (42), the magnetic patch (42) is an elastic structure, and the magnetic patch (42) and the inner wall of the expanded diameter bend (13) are attached to each other.

2. The aluminum-magnesium alloy die-casting method for automobile parts according to claim 1, characterized in that: When detecting the temperature difference at each point of the circulating water circuit to be detected, the water inlet speed, water inlet temperature and detection time node are kept consistent with those of the control group.

3. The aluminum-magnesium alloy die-casting method for automobile parts according to claim 1, characterized in that: The offset inclined tube (12) is arranged obliquely, and the end of the rectangular tube (11) on the water inlet side and the end of the offset inclined tube (12) on the water outlet side are staggered and intersected with each other.

4. The aluminum-magnesium alloy die-casting method for automobile parts according to claim 1, characterized in that: The expanded diameter curved pipe (13) and the two internal temperature sensors (22) form an internal temperature module, and the spatial cross-section in the middle of the expanded diameter curved pipe (13) is 2 to 5 times the cross-section of the rectangular pipe (11).

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