CN113385652B - Die casting control method - Google Patents
Die casting control method Download PDFInfo
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- CN113385652B CN113385652B CN202110660483.8A CN202110660483A CN113385652B CN 113385652 B CN113385652 B CN 113385652B CN 202110660483 A CN202110660483 A CN 202110660483A CN 113385652 B CN113385652 B CN 113385652B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
- B22D17/007—Semi-solid pressure die casting
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
- B22D17/20—Accessories: Details
- B22D17/32—Controlling equipment
Abstract
The invention relates to a die-casting control method, which comprises the following steps: a particulate solid metallic material is provided. The solid metallic material is heated to convert to a semi-solid slurry. And providing the target temperature of the semi-solid slurry, and keeping the deviation between the actual temperature of the semi-solid slurry and the target temperature within a set range. Therefore, the actual temperature of the semi-solid slurry can be prevented from being greatly fluctuated, and the actual temperature is ensured to be basically kept constant. After the semi-solid slurry with the basically constant temperature is input into a cavity of a die-casting die, the quality defect caused by large deviation between the actual temperature and the target temperature can be avoided, and the quality of die-casting products is improved. The phenomenon that different die-casting products have great quality difference due to large actual temperature difference of the semi-solid slurry can be avoided, and therefore the quality of each different die-casting product is kept consistent.
Description
Technical Field
The invention relates to the technical field of die casting, in particular to a die casting control method.
Background
Die casting can be divided into common liquid die casting and semi-solid slurry die casting, and compared with common liquid die casting, semi-solid slurry die casting has many obvious advantages: the solidification shrinkage of the casting is reduced, the size precision of the casting is high, the appearance quality is good, the machining amount is reduced, and even the casting without machining allowance can be obtained; the columnar crystal and the coarse dendrite in the conventional casting are eliminated, the casting structure is fine and compact, the distribution is uniform, and the macrosegregation does not exist; the metal mold filling is stable, free of turbulence and splashing, low in mold filling temperature and capable of prolonging the service life of the mold; the casting process is simplified, the energy consumption is reduced, the labor condition is improved, and the solidification speed is high, so that the production efficiency is high; the mechanical property of the casting is improved. Therefore, the semi-solid slurry die casting is widely applied in the compact manufacturing field, but the traditional semi-solid slurry die casting process usually has the defect that the product quality is difficult to further improve.
Disclosure of Invention
The invention solves a technical problem of how to improve the molding quality of die-casting products.
A die-casting control method comprising the steps of:
providing a particulate solid metallic material;
heating the solid metal material to convert to a semi-solid slurry; and
and providing the target temperature of the semi-solid slurry, and keeping the deviation of the actual temperature of the semi-solid slurry and the target temperature within a set range.
In one embodiment, the deviation of both the actual temperature of the semi-solid slurry and the target temperature is maintained within 2 ℃.
In one embodiment, the actual temperature of the semi-solid slurry is controlled by a proportional, derivative and integral algorithm.
In one embodiment, in the process of converting the solid metal material into the semi-solid slurry, a plurality of intermediate preset temperatures with different sizes are set between a normal temperature and the target temperature, any two adjacent intermediate preset temperatures are recorded as a front intermediate preset temperature and a rear intermediate preset temperature, the rear intermediate preset temperature is greater than the front intermediate preset temperature, the intermediate preset temperature adjacent to the target temperature is recorded as a rear intermediate preset temperature, the metal material reaching the front intermediate preset temperature is heated to the rear intermediate preset temperature after being kept at the temperature for a set time, and the metal material reaching the rear intermediate preset temperature is heated to the target temperature after being kept at the temperature for a set time.
In one embodiment, the number of the intermediate preset temperatures is not less than three, the holding time is five minutes to thirty minutes, and the holding time is inversely proportional to the number of the intermediate preset temperatures.
In one embodiment, the semi-solid slurry is fed to the barrel by translation and rotation of the screw.
In one embodiment, the amount of the semi-solid slurry input to the barrel is controlled by controlling the translational position and rotational speed of the screw.
In one embodiment, the solid metal material is a magnesium material, and the target temperature ranges from 580 ℃ to 620 ℃.
In one embodiment, during the process of cooling the semi-solid slurry in a die-casting mold to form a die-cast product, a plurality of intermediate preset temperatures with different sizes are set between a normal temperature and the target temperature, any two adjacent intermediate preset temperatures are recorded as a front intermediate preset temperature and a rear intermediate preset temperature, the value of the rear intermediate preset temperature is smaller than that of the front intermediate preset temperature, the intermediate preset temperature adjacent to the normal temperature is recorded as a tail intermediate preset temperature, the temperature of the metal material reaching the front intermediate preset temperature is cooled to the rear intermediate preset temperature after the heat preservation set time, and the temperature of the metal material reaching the tail intermediate preset temperature is reduced to the normal temperature after the heat preservation set time.
In one embodiment, the number of the intermediate preset temperatures is not less than three, the holding time is five minutes to fifteen minutes, and the holding time is inversely proportional to the number of the intermediate preset temperatures.
One technical effect of one embodiment of the invention is that: by keeping the deviation of the actual temperature of the semi-solid slurry and the target temperature within the set range, the actual temperature of the semi-solid slurry can be prevented from being greatly fluctuated, and the actual temperature is ensured to be basically kept constant. After the semi-solid slurry with the basically constant temperature is input into a cavity of a die-casting die, the quality defect caused by large deviation between the actual temperature and the target temperature can be avoided, and the quality of die-casting products is improved. The phenomenon that different die-casting products have great quality difference due to large actual temperature difference of the semi-solid slurry can be avoided, and therefore the quality of each different die-casting product is kept consistent.
Drawings
Fig. 1 is a flowchart of a die-casting control method according to an embodiment.
Detailed Description
To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "inner", "outer", "left", "right" and the like as used herein are for illustrative purposes only and do not represent the only embodiments.
Referring to fig. 1, the present invention provides a method for controlling die casting to provide a semi-solid slurry, and to introduce the semi-solid slurry into a cavity of a die casting mold, and then to cool the semi-solid slurry in the cavity to form a die casting product. The die-casting control method mainly comprises the following steps: s110, providing a granular solid metal material in a first step. And S120, heating the solid metal material to convert the solid metal material into semi-solid slurry. S130, in the third step, the target temperature of the semi-solid slurry is provided, so that the deviation between the actual temperature of the semi-solid slurry and the target temperature is kept within a set range.
First embodiment
The granular solid metal material can be magnesium metal, and the granular solid metal material can also be replaced by flaky solid metal material. Of course, the solid metal material may be other metal materials such as aluminum. When the solid metal material is put into a heater to be heated and raised to the target temperature, the solid metal material is converted into viscous semi-solid slurry. Taking magnesium metal as an example, when liquid die casting is used, the target temperature will be 660 ℃ to 670 ℃, at which time the solid magnesium metal can be converted to liquid magnesium at the target temperature. And when the semi-solid slurry is used for die casting, the target temperature may be set to 580 to 620 ℃. It is apparent that the target temperature for the conversion of solid magnesium metal to a semi-solid slurry is significantly lower than the target temperature for the conversion of solid magnesium metal to liquid magnesium. Compared with the common liquid die casting, the semi-solid die casting has the advantages that the required target temperature is obviously reduced, so that the heating time of solid metal and the consumption of heat energy can be reduced, the forming efficiency of die casting products can be improved, and the energy consumption is reduced to reduce the manufacturing cost of the die casting products. On the other hand, the damage of the high temperature of the magnesium liquid to the die-casting die can be avoided, the service life of the die-casting die is prolonged, and therefore the manufacturing cost of die-casting products can be further reduced by reducing the loss cost of the die-casting die.
After the solid metal material is converted into the semi-solid slurry, the deviation between the actual temperature of the semi-solid slurry and the target temperature is kept within a set range, which can be set to 2 ℃, that is, the deviation between the actual temperature of the solid slurry and the target temperature is kept within 2 ℃, in other words, the actual temperature cannot be higher than the target temperature by more than 2 ℃ and the actual temperature cannot be lower than the target temperature by more than 2 ℃. For example, for magnesium metal, the target temperature may be set to 600 ℃, in which case, when the actual temperature of the semi-solid slurry is controlled, the lowest value of the actual temperature is 598 ℃, and the highest value of the actual temperature is 602 ℃, that is, the actual temperature of the semi-solid slurry is guaranteed to float between 598 ℃ and 602 ℃.
By keeping the deviation of the actual temperature of the semi-solid slurry and the target temperature within the set range, the actual temperature of the semi-solid slurry can be prevented from being greatly fluctuated, and the actual temperature is ensured to be basically kept constant. After the semi-solid slurry with the basically constant temperature is input into a cavity of a die-casting die, the phenomenon that different die-casting products have great quality difference due to great actual temperature difference of the semi-solid slurry can be avoided, for example, the great quality difference can be expressed as that different die-casting products have great difference in the aspects of compactness and distribution uniformity of tissues, mechanical properties and the like, so that the quality of each different die-casting product is ensured to be consistent. The quality defect caused by large deviation between the actual temperature and the target temperature can be avoided, and the quality of the die-casting product is further improved.
In order to keep the deviation of the actual temperature of the semi-solid slurry from the target temperature within a set range, the actual temperature of the semi-solid slurry can be controlled by a three-in-one algorithm (i.e., PID algorithm) including Proportional (proportionality), integral (Differential) and Differential (Integral). Specifically, the PID algorithm can monitor the actual temperature of the semi-solid slurry in real time through the following formula: y = K p [(b.w-x+(w-x)/T I .s+T d .s.(c.w-x)/a.T d .s+1]. Wherein, the value of y is Boolean quantity, the value thereof can be 0 or 1, and when the value of y is equal to 1, the heater heats; when the value of y is equal to 0, the heater stops heating. K is p Is a proportional gain; s is the Laplace operator; b is a proportional action weight; w is the target temperature; x is the temperature; t is I Is the integration action time; t is d Is the differential action time; a is a differential delay coefficient (differential delay T) I ＝a.T d ) (ii) a c is the differential weight. For example, when the y-value output is 1 and the output frequency is high, the heater heating frequency is faster, and as the difference between the actual temperature and the target temperature is smaller, the y-value output is 1 and the output frequency is lower. When the deviation between the actual temperature and the target temperature is within the set range, the y value may be output as 0, at which time the heater will stop heating. Therefore, the actual temperature of the semi-solid slurry is controlled through the algorithm, and the deviation between the actual temperature and the target temperature can be ensured to be always within the set range.
In the process of converting a solid metal material into a semi-solid slurry, a plurality of intermediate preset temperatures with different sizes are set between normal temperature and a target temperature, any two adjacent intermediate preset temperatures are recorded as a front intermediate preset temperature and a rear intermediate preset temperature, the value of the rear intermediate preset temperature is greater than that of the front intermediate preset temperature, the intermediate preset temperature adjacent to the target temperature is recorded as a tail intermediate preset temperature, the temperature of the metal material reaching the front intermediate preset temperature is raised to the rear intermediate preset temperature after the metal material reaches the tail intermediate preset temperature for a set time, and the temperature of the metal material reaching the tail intermediate preset temperature is raised to the target temperature after the metal material reaches the tail intermediate preset temperature for a set time. In short, the solid metal material is converted into semi-solid slurry by means of stepwise temperature rise. The number of the middle preset temperature can be not less than three, and the heat preservation time can be five minutes to thirty minutes.
For example, for magnesium metal, when the target temperature is 600 ℃, the intermediate preset temperatures may be set to three, and the three preset temperatures may be 100 ℃, 250 ℃, and 400 ℃ in order from small to large. Firstly, heating the solid metal material from normal temperature to 100 ℃, and then keeping the temperature of the solid metal material at 100 ℃ for five to thirty minutes, namely keeping the temperature of the solid metal material constant at 100 ℃ in the heat preservation time period. And secondly, heating the metal material after the heat preservation time is finished from 100 ℃ to 250 ℃, and then preserving the heat of the metal material at 250 ℃ for five to thirty minutes, namely keeping the metal material at 250 ℃ constant in the heat preservation time period. And thirdly, heating the metal material after the heat preservation time is finished from 250 ℃ to 400 ℃, and then preserving the heat of the metal material at 400 ℃ for five to thirty minutes, namely keeping the temperature of the metal material constant at 400 ℃ in the heat preservation time period. And fourthly, heating the metal material after the heat preservation time is finished from 400 ℃ to 600 ℃, and at the moment, converting the metal material which is initially in a solid state into viscous semi-solid slurry. When the intermediate preset temperature is lower than three or higher than three, the solid metal material can be heated by the above heating method until the solid metal material is converted into the semi-solid slurry.
The holding time may be inversely proportional to the number of intermediate preset temperatures, for example, when the number of intermediate preset temperatures is three, the holding time at each intermediate preset temperature may be ten minutes; when the number of the intermediate preset temperatures is four, the heat-preserving time at each intermediate preset temperature can be reduced to five minutes.
If the solid metal material is directly heated from normal temperature to the target temperature by adopting a continuous heating mode so as to be converted into the semi-solid slurry, the temperature can be suddenly changed in a short time, the solid metal material is heated and unbalanced to melt, and grains in the semi-solid slurry are uneven, so that the structure compactness and the distribution uniformity of a die-cast product after molding are influenced; the surface roughness of the die-casting product, namely the appearance quality of the die-casting product, can also be influenced; meanwhile, unreleased residual stress can exist in the die-casting product, so that the mechanical property and the service life of the die-casting product can be influenced.
In the die-casting product manufactured by the die-casting control method according to the embodiment, the solid metal material is converted into the semi-solid slurry by adopting a stepwise temperature rise manner. The method can effectively prevent the temperature from generating sudden change in a short time, ensure that all parts of the solid metal material are heated in a balanced manner and melted uniformly, and ensure the homogenization of crystal grains in the semi-solid slurry, thereby improving the tissue compactness and the distribution uniformity of the die-casting product, reducing the surface roughness of the die-casting product and improving the appearance quality of the die-casting product. And in addition, residual internal stress in the die-casting product is effectively eliminated, the mechanical property of the die-casting product is improved, and the service life of the die-casting product is prolonged.
After the solid metal material is converted into the semi-solid slurry, the semi-solid slurry may be transferred to the barrel by the screw. Specifically, the screw can generate a rotation motion and a linear translation motion simultaneously, and the semi-solid slurry can be conveyed to the charging barrel under the action of the translation and the rotation. Meanwhile, the amount of the semi-solid slurry input into the charging barrel can be adjusted by controlling the translation position of the screw and the rotation speed, so that the requirement of a die-casting product on the amount of the semi-solid slurry is met. And after the semi-solid slurry is transferred to the charging barrel, the semi-solid slurry is injected into a cavity of the die-casting die from the charging barrel through a hammer head of the die-casting machine. After the semi-solid slurry is filled in the cavity of the die-casting die, the semi-solid slurry can be cooled, and finally the semi-solid slurry is cooled and solidified to form a required die-casting product. In the cooling process, the semi-solid slurry can be cooled to normal temperature in a continuous cooling mode, so that the semi-solid slurry is solidified to form a die-casting product.
Second embodiment
The die-casting control method of this second embodiment is mainly different from the first embodiment described above in that: and in the process of cooling the semi-solid slurry in a die-casting die to form a die-casting product, cooling the semi-solid slurry from a target temperature by adopting a stepped cooling mode to finally solidify to form the normal-temperature die-casting product.
The granular solid metal material can be magnesium metal, and the granular solid metal material can also be replaced by flaky solid metal material. Of course, the solid metal material may be other metal materials such as aluminum. When the solid metal material is put into a heater to be heated and raised to the target temperature, the solid metal material is converted into viscous semi-solid slurry. Taking magnesium metal as an example, when liquid die casting is used, the target temperature will be 660 ℃ to 670 ℃, at which point the solid magnesium metal can be converted to liquid magnesium at the target temperature. And when the semi-solid slurry is used for die casting, the target temperature may be set to 580 to 620 ℃. It is apparent that the target temperature for the conversion of solid magnesium metal to a semi-solid slurry is significantly lower than the target temperature for the conversion of solid magnesium metal to liquid magnesium. Compared with common liquid die casting, the semi-solid die casting has obviously lowered target temperature, and this can reduce the heating time and heat energy consumption of solid metal, raise the forming efficiency of die casting product and reduce the energy consumption to lower the production cost of die casting product. On the other hand, the damage of the high temperature of the magnesium liquid to the die-casting die can be avoided, the service life of the die-casting die is prolonged, and therefore the manufacturing cost of die-casting products can be further reduced by reducing the loss cost of the die-casting die.
After the solid metal material is converted into the semi-solid slurry, the deviation between the actual temperature of the semi-solid slurry and the target temperature is kept within a set range, which can be set to 2 ℃, that is, the deviation between the actual temperature of the solid slurry and the target temperature is kept within 2 ℃, in other words, the actual temperature cannot be higher than the target temperature by more than 2 ℃ nor lower than the target temperature by more than 2 ℃. For example, for magnesium metal, the target temperature may be set to 600 ℃, in which case, when the actual temperature of the semi-solid slurry is controlled, the lowest value of the actual temperature is 598 ℃, and the highest value of the actual temperature is 602 ℃, that is, the actual temperature of the semi-solid slurry is guaranteed to float between 598 ℃ and 602 ℃.
By keeping the deviation of the actual temperature of the semi-solid slurry and the target temperature within the set range, the actual temperature of the semi-solid slurry can be prevented from being greatly fluctuated, and the actual temperature is ensured to be basically kept constant. After the semi-solid slurry with the basically constant temperature is input into a cavity of a die-casting die, the phenomenon of great quality difference of different die-casting products due to great actual temperature difference of the semi-solid slurry can be avoided, for example, the great quality difference can be expressed as great difference of different die-casting products in the aspects of compactness, distribution uniformity, mechanical property and the like of the structure, so that the quality of each different die-casting product is ensured to be consistent.
In order to keep the deviation of the actual temperature of the semi-solid slurry from the target temperature within a set range, the actual temperature of the semi-solid slurry can be controlled by a three-in-one algorithm (i.e., PID algorithm) including Proportional (proportionality), integral (Differential) and Differential (Integral). Specifically, the PID algorithm can monitor the actual temperature of the semi-solid slurry in real time through the following formula: y = K p [(b.w-x+(w-x)/T I .s+T d .s.(c.w-x)/a.T d .s+1]. Wherein, the value of y is Boolean quantity, the value thereof can be 0 or 1, and when the value of y is equal to 1, the heater heats; when the value of y is equal to 0, the heater stops heating. K p Is a proportional gain; s is the Laplace operator; b is a proportional action weight; w is the target temperature; x is the temperature; t is a unit of I Is the integration action time; t is d Is the differential action time; a is a differential delay coefficient (differential delay T) I ＝a.T d ) (ii) a c is the differential weight. For example, when the y-value output is 1 and the output frequency is high, the heater heating frequency is faster, and as the difference between the actual temperature and the target temperature is smaller, the y-value output is 1 and the output frequency is lower. When the deviation between the actual temperature and the target temperature is within the set range, the y value can be output as 0, and the heater stops addingAnd (4) heating. Therefore, the actual temperature of the semi-solid slurry is controlled through the algorithm, and the deviation between the actual temperature and the target temperature can be ensured to be always within the set range.
In the process of transferring the solid metal material into the semi-solid slurry, a plurality of intermediate preset temperatures with different sizes are set between normal temperature and target temperature, any two adjacent intermediate preset temperatures are recorded as a front intermediate preset temperature and a rear intermediate preset temperature, the value of the rear intermediate preset temperature is larger than that of the front intermediate preset temperature, the intermediate preset temperature adjacent to the target temperature is recorded as a tail intermediate preset temperature, the temperature of the metal material reaching the front intermediate preset temperature is raised to the rear intermediate preset temperature after the metal material reaches the tail intermediate preset temperature after the metal material is kept for a set time, and the temperature of the metal material reaching the tail intermediate preset temperature is raised to the target temperature after the metal material is kept for a set time. In short, a solid metal material is converted into a semi-solid slurry by adopting a step-type heating mode. The number of the middle preset temperature can be not less than three, and the heat preservation time can be five minutes to thirty minutes.
For example, for magnesium metal, when the target temperature is 600 ℃, the intermediate preset temperatures may be set to three, and the three preset temperatures may be 100 ℃, 250 ℃, and 400 ℃ in order from small to large. Firstly, heating the solid metal material from normal temperature to 100 ℃, and then keeping the temperature of the solid metal material at 100 ℃ for five to thirty minutes, namely keeping the temperature of the solid metal material constant at 100 ℃ in the heat preservation time period. And secondly, heating the metal material after the heat preservation time is finished from 100 ℃ to 250 ℃, and then preserving the heat of the metal material at 250 ℃ for five to thirty minutes, namely keeping the metal material at 250 ℃ constant in the heat preservation time period. And thirdly, heating the metal material after the heat preservation time is finished from 250 ℃ to 400 ℃, and then preserving the heat of the metal material at 400 ℃ for five to thirty minutes, namely keeping the temperature of the metal material constant at 400 ℃ in the heat preservation time period. And fourthly, heating the metal material after the heat preservation time is finished from 400 ℃ to 600 ℃, and at the moment, converting the metal material which is initially in a solid state into viscous semi-solid slurry. When the intermediate preset temperature is lower than three or higher than three, the solid metal material can be heated by the above heating method until the solid metal material is converted into the semi-solid slurry.
For the die-casting product manufactured by the die-casting control method of the embodiment, the solid metal material is converted into the semi-solid slurry by adopting a step-type temperature rise mode. The method can effectively prevent the temperature from generating sudden change in a short time, ensure that all parts of the solid metal material are heated in a balanced manner and melted uniformly, and ensure the homogenization of crystal grains in the semi-solid slurry, thereby improving the tissue compactness and the distribution uniformity of the die-casting product, reducing the surface roughness of the die-casting product and improving the appearance quality of the die-casting product. And in addition, the residual internal stress in the die-casting product is effectively eliminated, the mechanical property of the die-casting product is improved, and the service life of the die-casting product is prolonged.
After the solid metallic material is converted into the semi-solid slurry, the semi-solid slurry may be transferred to the barrel by the screw. Specifically, the screw can generate a rotation motion and a linear translation motion simultaneously, and the semi-solid slurry can be conveyed to the charging barrel under the action of the translation and the rotation. Meanwhile, the amount of the semi-solid slurry input into the charging barrel can be adjusted by controlling the translation position of the screw and the rotation speed, so that the requirement of a die-casting product on the amount of the semi-solid slurry is met. After the semi-solid slurry is transferred to the charging barrel, the semi-solid slurry is injected into a die cavity of a die-casting die from the charging barrel through a hammer head of the die-casting machine. After the semi-solid slurry is filled in the cavity of the die-casting die, the semi-solid slurry can be cooled, and finally the semi-solid slurry is cooled and solidified to form a required die-casting product.
In the process of cooling the semi-solid slurry in a die-casting die to form a die-casting product, a plurality of different intermediate preset temperatures are set between normal temperature and target temperature, any two adjacent intermediate preset temperatures are recorded as a front intermediate preset temperature and a rear intermediate preset temperature, the value of the rear intermediate preset temperature is smaller than that of the front intermediate preset temperature, the intermediate preset temperature adjacent to the normal temperature is recorded as a tail intermediate preset temperature, the temperature of the metal material reaching the front intermediate preset temperature is cooled to the rear intermediate preset temperature after the heat preservation set time, and the temperature of the metal material reaching the tail intermediate preset temperature is reduced to the normal temperature after the heat preservation set time. In short, a solid metal material is solidified to form a die-casting product in a stepped cooling mode. The number of the middle preset temperature can be not less than three, and the heat preservation time can be five minutes to fifteen minutes.
For example, for magnesium metal, when the target temperature is 600 ℃, the intermediate preset temperatures may be set to three, and the three preset temperatures may be 500 ℃, 350 ℃, and 150 ℃ in order from the large to the small. In the first step, the semi-solid slurry is cooled from the target temperature to 500 ℃, and then the metal material at 500 ℃ is kept at the temperature for five to fifteen minutes, namely, the metal material is kept constant at 500 ℃ in the temperature keeping time period. And secondly, cooling the metal material after the heat preservation time is finished from 500 ℃ to 350 ℃, and then preserving the heat of the metal material at 350 ℃ for five to fifteen minutes, namely keeping the temperature of the metal material constant at 350 ℃ in the heat preservation time period. And thirdly, cooling the metal material after the heat preservation time is finished from 350 ℃ to 150 ℃, and then preserving the heat of the metal material at 400 ℃ for five to fifteen minutes, namely keeping the temperature of the metal material constant at 150 ℃ in the heat preservation time period. And fourthly, reducing the temperature of the metal material after the heat preservation time is finished from 150 ℃ to normal temperature, and solidifying the metal material which is initially the semi-solid slurry to form a die-casting product. When the middle preset temperature is lower than three or higher than three, the semi-solid slurry can be cooled by referring to the heating method until the semi-solid slurry is solidified into a solid die-casting product.
The holding time may be inversely proportional to the number of intermediate preset temperatures, for example, when the number of intermediate preset temperatures is three, the holding time at each intermediate preset temperature may be fifteen minutes; when the number of the intermediate preset temperatures is four, the heat-preserving time at each intermediate preset temperature can be reduced to three minutes.
The solid metal material is converted into semi-solid slurry by adopting a step-type heating mode. The rapid temperature change can be effectively prevented in a short time, so that the cooling speed of each part inside the metal material is kept consistent, the residual internal stress in the die-casting product is effectively eliminated, and the mechanical property and the service life of the die-casting product are improved. Meanwhile, the die-casting product is prevented from being deformed due to the fact that cooling speed is inconsistent, and the size precision of the die-casting product is improved.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is specific and detailed, but not to be understood as limiting the scope of the invention. It should be noted that various changes and modifications can be made by those skilled in the art without departing from the spirit of the invention, and these changes and modifications are all within the scope of the invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (9)
1. A die-casting control method, characterized by comprising the steps of:
providing a particulate solid metallic material;
heating the solid metal material by a heater to convert the solid metal material into a semi-solid slurry; and
providing a target temperature of the semi-solid slurry, and keeping the deviation between the actual temperature of the semi-solid slurry and the target temperature within a set range;
controlling the actual temperature of the semi-solid slurry through a proportional, differential and integral three-in-one algorithm; y = K p [(b.w-x+(w-x)/T I .s+T d .s.( c.w-x )/a.T d .s+1]Wherein, the value of y is Boolean quantity, the value thereof can be 0 or 1, and when the value of y is equal to 1, the heater heats; when the value of y is equal to 0, the heater stops heating, K p Is a proportional gain; s is the Laplace operator; b is a proportional action weight; w is the target temperature; x is the temperature; t is a unit of I Is the integration action time; t is a unit of d Is the differential action time; a is a differential delay coefficient, T I =a.T d (ii) a c is a differential action weight, when the y value is 1 and the output frequency is higherAnd when the heating frequency of the heater is faster, the y value output is 1 and the output frequency is lower as the difference between the actual temperature and the target temperature is smaller, and when the deviation between the actual temperature and the target temperature is within the set range, the y value output is 0, and the heater stops heating.
2. The die casting control method according to claim 1, characterized in that a deviation of both the actual temperature of the semi-solid slurry and the target temperature is maintained within 2 ℃.
3. The die-casting control method according to claim 1, wherein a plurality of intermediate preset temperatures having different magnitudes are set between a normal temperature and the target temperature in the process of converting the solid metal material into the semi-solid slurry, any two adjacent intermediate preset temperatures are recorded as a front intermediate preset temperature and a rear intermediate preset temperature, the rear intermediate preset temperature is greater than the front intermediate preset temperature, the intermediate preset temperature adjacent to the target temperature is recorded as a rear intermediate preset temperature, the metal material reaching the front intermediate preset temperature is heated to the rear intermediate preset temperature after being kept warm for a set time, and the metal material reaching the rear intermediate preset temperature is heated to the target temperature after being kept warm for a set time.
4. The die-casting control method according to claim 3, characterized in that the number of the intermediate preset temperatures is not less than three, the keeping warm time is five minutes to thirty minutes, and the keeping warm time is inversely proportional to the number of the intermediate preset temperatures.
5. The die-casting control method according to claim 1, wherein after the solid metal material is converted into the semi-solid slurry, the semi-solid slurry is inputted into the barrel by translation and rotation of the screw, after the semi-solid slurry is transferred to the barrel, the semi-solid slurry is shot from the barrel into the cavity of the die-casting mold by a ram of the die-casting machine, and after the semi-solid slurry is filled in the cavity of the die-casting mold, the semi-solid slurry is cooled and solidified to form the die-casting product.
6. The die-casting control method according to claim 5, wherein the amount of the semi-solid slurry input to the barrel is controlled by controlling a translational position and a rotational speed of the screw.
7. The die-casting control method according to claim 1, wherein the solid metal material is a magnesium material, and the target temperature is in a range of 580 ℃ to 620 ℃.
8. The die-casting control method according to claim 5, wherein a plurality of intermediate preset temperatures having different sizes are set between a normal temperature and the target temperature during cooling of the semi-solid slurry in a die-casting mold to form a die-cast product, any two adjacent intermediate preset temperatures are recorded as a former intermediate preset temperature and a latter intermediate preset temperature, a value of the latter intermediate preset temperature is smaller than a value of the former intermediate preset temperature, an intermediate preset temperature adjacent to the normal temperature is recorded as a latter intermediate preset temperature, the metal material reaching the former intermediate preset temperature is cooled to the latter intermediate preset temperature after being kept warm for a set time, and the metal material reaching the latter intermediate preset temperature is cooled to the normal temperature after being kept warm for the set time.
9. The die-casting control method according to claim 8, characterized in that the number of the intermediate preset temperatures is not less than three, the keeping time is five minutes to fifteen minutes, and the keeping time is inversely proportional to the number of the intermediate preset temperatures.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104096815A (en) * | 2014-06-30 | 2014-10-15 | 南昌大学 | Semi-solid state machining and integrating system |
| CN104550861A (en) * | 2013-10-24 | 2015-04-29 | 青岛和德隆机械有限公司 | A291D magnesium alloy semi-solid sizing agent near-liquidus preparation technology |
| CN105855496A (en) * | 2016-04-08 | 2016-08-17 | 珠海市润星泰电器有限公司 | Continuous semisolid die casting production method and system |
| CN109402442A (en) * | 2018-12-10 | 2019-03-01 | 中北大学 | A kind of die casting preparation method of graphene reinforced aluminum matrix composites |
| CN109865813A (en) * | 2019-04-26 | 2019-06-11 | 金雅豪精密金属科技(东莞)有限公司 | Hot type semisolid pressure casting machine |
| CN111438905A (en) * | 2020-02-27 | 2020-07-24 | 宁波创元信息科技有限公司 | Temperature control system and method for injection mold |
| CN111940699A (en) * | 2020-07-20 | 2020-11-17 | 深圳市深汕特别合作区力劲科技有限公司 | Feeding device and die casting machine |
| CN213104394U (en) * | 2020-07-20 | 2021-05-04 | 深圳市深汕特别合作区力劲科技有限公司 | Die casting machine |
-
2021
- 2021-06-15 CN CN202110660483.8A patent/CN113385652B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104550861A (en) * | 2013-10-24 | 2015-04-29 | 青岛和德隆机械有限公司 | A291D magnesium alloy semi-solid sizing agent near-liquidus preparation technology |
| CN104096815A (en) * | 2014-06-30 | 2014-10-15 | 南昌大学 | Semi-solid state machining and integrating system |
| CN105855496A (en) * | 2016-04-08 | 2016-08-17 | 珠海市润星泰电器有限公司 | Continuous semisolid die casting production method and system |
| CN109402442A (en) * | 2018-12-10 | 2019-03-01 | 中北大学 | A kind of die casting preparation method of graphene reinforced aluminum matrix composites |
| CN109865813A (en) * | 2019-04-26 | 2019-06-11 | 金雅豪精密金属科技(东莞)有限公司 | Hot type semisolid pressure casting machine |
| CN111438905A (en) * | 2020-02-27 | 2020-07-24 | 宁波创元信息科技有限公司 | Temperature control system and method for injection mold |
| CN111940699A (en) * | 2020-07-20 | 2020-11-17 | 深圳市深汕特别合作区力劲科技有限公司 | Feeding device and die casting machine |
| CN213104394U (en) * | 2020-07-20 | 2021-05-04 | 深圳市深汕特别合作区力劲科技有限公司 | Die casting machine |
Non-Patent Citations (1)
| Title |
|---|
| 运用灰色预测与模糊加权PID的反应釜温度控制;魏小宇，郑晟;《重庆理工大学学报》;20190228;第82-86页 * |
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