CN109834181B - Hot-press forming device and hot-press forming method for magnesium alloy plate, magnesium alloy plate and application of magnesium alloy plate - Google Patents
Hot-press forming device and hot-press forming method for magnesium alloy plate, magnesium alloy plate and application of magnesium alloy plate Download PDFInfo
- Publication number
- CN109834181B CN109834181B CN201711193977.XA CN201711193977A CN109834181B CN 109834181 B CN109834181 B CN 109834181B CN 201711193977 A CN201711193977 A CN 201711193977A CN 109834181 B CN109834181 B CN 109834181B
- Authority
- CN
- China
- Prior art keywords
- die
- magnesium alloy
- blank
- hot
- cylinder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Shaping Metal By Deep-Drawing, Or The Like (AREA)
Abstract
The invention relates to the field of magnesium alloy plate stamping preparation, and discloses a magnesium alloy plate hot-press forming device, a hot-press forming method, a magnesium alloy plate and application thereof, wherein the magnesium alloy plate hot-press forming device comprises an upper die and a lower die, the upper die is connected with the upper die, the lower die is connected with a lower die plate, the upper die is provided with a preforming oil cylinder, a discharging block and a concave die, and the lower die is provided with a convex die, a blank holder and a lower ejection cylinder; the preforming oil cylinder drives the discharging block to vertically lift, and the lower jacking cylinder drives the blank holder to vertically lift; the master cylinder is arranged in an overhead mode, the master cylinder drives the upper die plate to vertically lift, and then the upper die plate drives the female die to vertically lift. The product prepared by the hot press molding method by adopting the device has good drawing effect, no scratch on the surface and no crack on the fillet, and can be applied to the automobile seat.
Description
Technical Field
The invention relates to the field of magnesium alloy plate stamping preparation, in particular to a hot-press forming device and a hot-press forming method for a magnesium alloy plate, the magnesium alloy plate and application thereof.
Background
CN02144943.0 relates to magnesium alloy preparation technology, specifically is a magnesium alloy sheet processing method and special hot stamping device. The magnesium alloy shell-shaped piece is formed by adopting a plate stamping technology, a die is preheated to 500 ℃ for 200 plus materials, the magnesium alloy plate is heated to 350 ℃ for 200 plus materials, the plate is put into the die after being coated with a lubricant, the drawing ratio is controlled within the range of 1.5-3, and the drawing speed is 50-80 mm/min. The invention improves the blank shape and the lubricating mode, thereby well improving the machinability of the material, improving the product quality, improving the production efficiency and reducing the cost.
CN201580014686.2 relates to a method for processing extruded profile sections by means of hot finishing and/or hot pressing and/or cutting operations and/or perforation operations in terms of their profile, comprising the following method steps: pushing the profile section (1) heated to a temperature in the range of 250 ℃ to 450 ℃ into a finishing die (2) divided into two parts and preheated to a temperature in the range of 300 ℃ to 600 ℃; the finishing tool (2) is pressed by means of one or more press cylinders (3) of a press (4). The device for carrying out the method is formed by a press (4) and a sizing die, wherein the sizing die (2) is formed by two relatively movable die halves I, II, between which the profile section (1) is pushed.
CN201110085866.3 discloses a progressive die for producing magnesium alloy thin shell parts by adopting magnesium alloy strip materials or strip materials with the thickness of 0.1-4mm to carry out continuous warm stamping forming. The main procedures comprise: blanking the shape and the positioning hole of the thin shell blank, deep drawing, punching and blanking. The drawing process is the most important, and one or more times of drawing can be adopted and the drawing die is provided with a shaping part. In order to ensure the smooth drawing of the thin shell piece, the drawing female die is made of high-hardness high-temperature-resistant engineering plastics or processed die steel, and the surfaces of the die and the blank are coated with lubricating liquid. The progressive die is provided with a preheating backing plate, and the progressive die is preheated to 150 ℃ and 300 ℃ by adopting a circulating heat conduction oil or resistance rod adding mode. The blank is preheated to 160-260 ℃.
CN200510046960.2 relates to alloy sheet stamping forming technology, in particular to a warm forming method of a magnesium alloy mobile phone shell and a special die thereof, which are mainly applied to the warm drawing process forming of the magnesium alloy sheet. The process flow is as follows: heating a blank holder and a female die → coating a lubricant on the die → coating a lubricant on a blank → heating the blank → preheating a male die → drawing and forming. The blank holder and the female die are heated to 180 ℃ in 170-. The die structure adopts a sectional type combined drawing female die, so that the die is simple to replace, and the service life can be prolonged by 3 times; the forming cushion block in the combined drawing female die improves the stress state of a formed piece, and the yield is improved. The invention has the advantages that: the process parameters are accurately controlled, the material utilization rate is high, the surface quality of the product is good, the rigidity is strong, and the shape and size precision is high; the die has long service life, low production cost and simple process and device.
CN200810228072.6 discloses a deep drawing forming method of a magnesium alloy tailor-welded blank, which comprises the following processes: (1) preparing a blank, namely coating a lubricant on the magnesium alloy tailor-welded blank; (2) preheating a mould, heating the mould to a preset temperature, putting a blank when the temperature measured by a thermocouple reaches a preset value, and heating the blank together with the mould; (3) heating the blank, namely heating the blank together with a die for 5-10 minutes and preparing to begin drawing and forming; (4) drawing forming, wherein the drawing speed is controlled within a preset range, and the drawing forming is started; (5) and after the forming is finished and the drawing forming is finished, withdrawing the workpiece. The process in the form is a drawing process for tailor-welded plates, can be drawn in one direction at a time, and can only meet the process discussion of laboratory properties and the performance parameter test of the plates. The application of this process is generally small products with a simple structure, such as a thermoformed sheet blank (AZ31) of 120mm x 70mm size with a fillet radius of 30 mm. In actual product requirements, a plurality of sheet metal products are designed with a structure combining forward drawing and reverse drawing, the overall dimension of the product is larger, and qualified products cannot be manufactured by adopting the process in the form. At present, no large-tonnage hot-pressing equipment can realize the forward and reverse drawing process of the magnesium alloy plate.
Therefore, the research and development of the hot-press forming device which is suitable for large tonnage and can realize the positive and negative drawing process of the magnesium alloy plate are of great significance.
Disclosure of Invention
The invention aims to overcome the problems in the prior art and provides a hot-press forming device and a hot-press forming method for a magnesium alloy plate, the magnesium alloy plate and application thereof, the hot-press forming device for the magnesium alloy plate is suitable for products or parts with complex structures and large sizes, the hot-press forming method for the magnesium alloy plate adopts a one-step forming process, can realize the forming in the positive and negative directions in a set of drawing die, and has the advantages of low relative energy consumption, high yield of finished products (the yield is more than or equal to 96%) and good dimensional precision of the products.
In order to achieve the above object, in a first aspect, the present invention provides a magnesium alloy plate hot press forming apparatus, wherein the magnesium alloy plate hot press forming apparatus includes an upper die 1, a lower die 2 and a main cylinder 15, wherein the upper die 1 is connected to an upper die plate 18, the lower die 2 is connected to a lower die plate 19, a preforming cylinder 4, a discharging block 5 and a female die 7 are arranged on the upper die 1, and a male die 8, a blank holder 9 and a lower top cylinder 17 are arranged on the lower die 2;
the preforming oil cylinder 4 drives the discharging block 5 to vertically lift, and the lower jacking cylinder 17 drives the blank holder 9 to vertically lift;
the master cylinder is arranged in an overhead manner, the master cylinder drives the upper template 18 to vertically lift, and then the upper template 18 drives the female die 7 to vertically lift.
Preferably, a heat insulation block 14 is arranged between the preforming oil cylinder 4 and the discharging block 5, and a water cooling channel 13 is arranged on the preforming oil cylinder 4;
preferably, the preforming cylinder 4 is provided with a sealing ring.
Preferably, a heat insulation block and a water cooling channel are arranged between the upper template 18 and the lower template 19, and the guide structures of the upper die 1 and the lower die 2 are provided with the water cooling channel.
Preferably, the blank holder 9 is sleeved outside the bottom of the male die 8, and the female die 7 is sleeved outside the bottom of the discharging block 5.
Preferably, the female die 7, the male die 8 and the blank holder 9 are all in a circular ring structure, and the circular rings of the female die 7, the male die 8 and the blank holder 9 are radially provided with accommodating holes, and a heating rod and a thermocouple connected with a power supply are inserted into the accommodating holes.
Preferably, the female die 7, the male die 8 and the blank holder 9 are all of a circular ring structure, and oil pipelines are radially arranged on the circular rings of the female die 7, the male die 8 and the blank holder 9, are provided with temperature sensors and are connected with an external high-temperature oil heating die temperature controller.
Preferably, the female die 7, the male die 8 and the discharging block 5 form a hot-press forming die, and preferably, the sizes and fit gaps of the female die 7, the male die 8 and the discharging block 5 are determined according to the shrinkage rate of the magnesium alloy plate to be hot-press formed after expansion with heat and contraction with cold.
Preferably, a mechanical limit structure is arranged between the female die 7 and the blank holder 9.
In a second aspect, the present invention provides a magnesium alloy plate hot press molding method, wherein the magnesium alloy plate hot press molding method includes the following steps:
(I) the preforming oil cylinder 4 drives the discharging block 5 to rise to the upper stop position, and the lower jacking cylinder 17 drives the blank holder 9 to rise to the upper stop position; and placing the blank on the surface of said blank holder 9;
(II) the main cylinder 15 drives the upper template 18 to move downwards to enable the lower surface of the periphery of the female die 7 to be close to but not contacted with the blank and preheat the blank; after the preheating is finished, the female die 7 continuously descends to tightly press the blank, so that the blank is clamped in a gap between the female die 7 and the blank holder 9;
(III) the preforming oil cylinder 4 drives the discharging block 5 to move downwards, and the blank is drawn downwards until the blank is drawn to the upper surface of the male die 8;
(IV) the main cylinder 15 continues to descend to drive the female die 7 to descend, and the female die 7 and the blank holder 9 clamp an external blank structure to perform flanging and deep drawing; and opening the mold and pushing out the magnesium alloy plate subjected to hot press molding.
Preferably, the driving speed of the preforming oil cylinder 4 is 10-60mm/min, and the driving pressure is 1-12 Mpa; the driving speed of the lower ejection cylinder 17 is 10-60mm/min, and the driving pressure is 1-12 Mpa; the driving speed of the main cylinder 15 is 10-60mm/min, and the driving pressure is 1-12 Mpa.
More preferably, the driving speed of the preforming oil cylinder 4 is 20-50mm/min, and the driving pressure is 2-8 Mpa; the driving speed of the lower ejection cylinder 17 is 20-50mm/min, and the driving pressure is 2-8 Mpa; the driving speed of the main cylinder 15 is 20-50mm/min, and the driving pressure is 2-8 Mpa.
Preferably, in step (I), the method further comprises heating the female die 7, the male die 8 and the binder 9, wherein:
the heating condition of the female die 7 is as follows: the heating temperature is 260 ℃ and 300 ℃, and the heating time is 35-45 minutes; the heating condition of the male die 8 is as follows: the heating temperature is 180 ℃ and 220 ℃, and the heating time is 35-45 minutes; the heating condition of the blank holder 9 is as follows: the heating temperature is 260 ℃ to 300 ℃, and the heating time is 35-45 minutes.
More preferably, the heating conditions of the female die 7 are: the heating temperature is 270-280 ℃, and the heating time is 38-42 minutes; the heating condition of the male die 8 is as follows: the heating temperature is 190-210 ℃, and the heating time is 38-42 minutes; the heating condition of the blank holder 9 is as follows: the heating temperature is 270-280 ℃, and the heating time is 38-42 minutes.
Preferably, the temperature difference formed between the lower mold 2 and the upper mold 1 is 10 to 100 ℃, preferably 15 to 80 ℃, and more preferably 20 to 40 ℃.
Preferably, the blank is sprayed with high temperature drawing oil, preferably the high temperature drawing oil is high temperature resistant all-mineral synthetic oil.
Preferably, in step (III), the ratio of the depth of drawing of the blank to the diameter of the blank is (0.6-1): 1, preferably (0.6-0.8): 1, more preferably 1: 1.
preferably, the magnesium alloy sheet is an AZ31B sheet, and the magnesium alloy sheet has a shrinkage rate of 0.2-0.4%, preferably 0.25-0.28%, and more preferably 0.267%.
In a third aspect, the invention provides a magnesium alloy sheet prepared by the forming method of the magnesium alloy sheet.
In a fourth aspect, the invention provides an application of the magnesium alloy sheet material in an automobile seat.
By adopting the technical scheme, the magnesium alloy plate hot-press forming device and the magnesium alloy plate hot-press forming method can be used for hot-press forming magnesium alloy plate parts with complex structures and large sizes, and are low in energy consumption and high in yield (the yield is more than or equal to 96%), and can be really applied in batches.
Drawings
FIG. 1 is a schematic view of mold opening in a magnesium alloy sheet hot press molding apparatus according to the present invention;
FIG. 2 is a schematic view of mold clamping in the magnesium alloy sheet hot press molding apparatus of the present invention;
FIG. 3 is a schematic detail view of a magnesium alloy sheet hot press molding apparatus according to the present invention;
FIG. 4 is a schematic view of a hot press molding apparatus for a magnesium alloy sheet according to the present invention;
fig. 5 shows a magnesium alloy sheet automobile seat manufactured by the hot press molding apparatus and the hot press molding method of the present invention.
Description of the reference numerals
1. Upper die 2, lower die 3, blank
4. Preforming oil cylinder 5, discharging block 6 and upper die base plate
7. Female die 8, male die 9 and blank holder
10. Lower die base plate 11, product 12 and guide pillar
13. Water-cooling channel 14, heat insulation block 15 and master cylinder
16. A tie bar 17, a lower top cylinder 18 and an upper template
19. Lower template
I. Mold opening state II and mold closing state
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.
In a first aspect, the present invention provides a magnesium alloy plate hot press forming device, wherein, as shown in fig. 1 to 4, the magnesium alloy plate hot press forming device comprises an upper die 1, a lower die 2 and a main cylinder 15, wherein the upper die 1 is connected with an upper die plate 18, the lower die 2 is connected with a lower die plate 19, a preforming oil cylinder 4, a discharging block 5 and a female die 7 are arranged on the upper die 1, and a male die 8, a blank holder 9 and a lower ejection cylinder 17 are arranged on the lower die 2;
the preforming oil cylinder 4 drives the discharging block 5 to vertically lift, and the lower jacking cylinder 17 drives the blank holder 9 to vertically lift;
the master cylinder is arranged in an overhead manner, the master cylinder drives the upper template 18 to vertically lift, and then the upper template 18 drives the female die 7 to vertically lift.
As can be seen from fig. 2, an upper die backing plate 6 is further arranged above the upper die plate, and a lower backing plate 10 is further arranged below the lower die plate; and a guide post 12 can be arranged in the upper die 1, wherein the product 11 can be formed in a die space formed by the female die 7, the male die 7 and the discharging block 5.
According to the magnesium alloy plate hot-press forming device, a heat insulation block 14 is arranged between the preforming oil cylinder 4 and the discharging block 5, and a water cooling channel 13 is arranged on the preforming oil cylinder 4.
Preferably, the preforming cylinder 4 is provided with a sealing ring, and in the present invention, the material of the sealing ring is not particularly limited, and for example, the sealing ring may be made of a high temperature resistant material.
According to the magnesium alloy plate hot-press forming device, the heat insulation block and the water cooling channel are arranged between the upper template 18 and the lower template 19, so that high temperature of the die is prevented from being conducted to an equipment actuating oil cylinder and other components needing low-temperature operation, and the water cooling channel is arranged on the guide structures of the upper die 1 and the lower die 2, so that the upper die and the lower die can be opened and closed smoothly.
According to the magnesium alloy plate hot-press forming device, the blank holder 9 is sleeved on the outer side of the bottom of the male die 8, and the female die 7 is sleeved on the outer side of the bottom of the discharging block 5.
According to the magnesium alloy plate hot-press forming device, the female die 7, the male die 8 and the blank holder 9 are all of a circular ring structure, accommodating holes are radially formed in the circular rings of the female die 7, the male die 8 and the blank holder 9, heating rods and thermocouples connected with a power supply are inserted into the accommodating holes, and different temperatures and temperature gradients can be set according to a hot forming process.
According to the magnesium alloy plate hot-press forming device, the female die 7, the male die 8 and the blank holder 9 are all of a circular ring structure, oil pipelines are radially arranged on the circular rings of the female die 7, the male die 8 and the blank holder 9, the oil pipelines are provided with temperature sensors and are connected with an external high-temperature oil heating die temperature machine, different temperatures and temperature gradients can be set according to a hot forming process, and the temperature sensors monitor the temperature of hydraulic oil in an oil cylinder.
According to the magnesium alloy plate hot-press forming device, the female die 7, the male die 8 and the discharging block 5 form a hot-press forming die, and preferably, the sizes and fit gaps of the female die 7, the male die 8 and the discharging block 5 are determined according to the shrinkage rate of the magnesium alloy plate to be hot-press formed after expansion with heat and contraction with cold.
According to the magnesium alloy plate hot-press forming device, a mechanical limiting structure is arranged between the female die 7 and the blank holder 9, and the gap between the female die 7 and the blank holder 9 is ensured to meet the condition that the blank drawing clamping force cannot exceed a certain range.
In addition, the magnesium alloy sheet material hot press molding apparatus of the present invention is provided with an electric control system, for example, a main cylinder for driving the upper die plate to vertically move up and down. The power of the main cylinder is much larger than that of the lower jacking cylinder and the preforming oil cylinder, and the lower jacking cylinder or the preforming oil cylinder can stably return under the action of the main cylinder. The die heating system is provided, can control the temperature of the die, is accurate in control precision, and has alarm functions of wire breakage, overload and the like. Wherein, be equipped with water cooling system, this water cooling system contains a cold water machine, valve and pipeline etc. can set up the cooling water temperature who gets into the mould according to the technology demand, has water-break, overtemperature alarm function. The hydraulic system is mainly used for controlling the actions of the main cylinder, the preforming oil cylinder and the jacking cylinder, and the pressure and the speed can be adjusted.
In a second aspect, the invention provides a magnesium alloy plate hot press molding method, wherein the magnesium alloy plate hot press molding method comprises the following steps:
(I) the preforming oil cylinder 4 drives the discharging block 5 to rise to the upper stop position, and the lower jacking cylinder 17 drives the blank holder 9 to rise to the upper stop position; and placing the blank on the surface of said blank holder 9;
(II) the main cylinder 15 drives the upper template 18 to move downwards to enable the lower surface of the periphery of the female die 7 to be close to but not contacted with the blank and preheat the blank; after the preheating is finished, the female die 7 continuously descends to tightly press the blank, so that the blank is clamped in a gap between the female die 7 and the blank holder 9;
(III) the preforming oil cylinder 4 drives the discharging block 5 to move downwards, and the blank is drawn downwards until the blank is drawn to the upper surface of the male die 8;
(IV) the main cylinder 15 continues to descend to drive the female die 7 to descend, and the female die 7 and the blank holder 9 clamp an external blank structure to perform flanging and deep drawing;
(V) lifting the main cylinder, ascending the blank holder and separating the product from the male die; the master cylinder continues to rise to reach the die opening state; the preforming oil cylinder drives the unloading block to move downwards and pushes out a product; and (5) receiving the product by using a tool.
In the whole process, the speed of the preforming oil cylinder, the speed and the pressure of the main cylinder can be adjusted according to the drawing rate of the product. The product has good deep drawing effect, no scratch on the surface and no crack on the fillet, and well utilizes the characteristic of excellent high-temperature thermal forming performance of the magnesium alloy plate.
According to the forming method, the driving speed of the preforming oil cylinder 4 can be 10-60mm/min, and the driving pressure can be 1-12 Mpa; the driving speed of the lower jacking cylinder 17 can be 10-60mm/min, and the driving pressure can be 1-12 Mpa; the driving speed of the main cylinder 15 can be 10-60mm/min, and the driving pressure can be 1-12 Mpa.
Preferably, the driving speed of the preforming oil cylinder 4 is 20-50mm/min, and the driving pressure is 2-8 Mpa; the driving speed of the lower ejection cylinder 17 is 20-50mm/min, and the driving pressure is 2-8 Mpa; the driving speed of the main cylinder 15 is 20-50mm/min, and the driving pressure is 2-8 Mpa.
The molding method according to the present invention, wherein, in the step (I), the step (ii) further comprises heating the female mold 7, the male mold 8 and the blank holder 9, wherein:
the heating condition of the female die 7 can be as follows: the heating temperature is 260 ℃ and 300 ℃, and the heating time is 35-45 minutes; the heating condition of the male die 8 can be as follows: the heating temperature is 180 ℃ and 220 ℃, and the heating time is 35-45 minutes; the heating condition of the blank holder 9 can be as follows: the heating temperature is 260 ℃ to 300 ℃, and the heating time is 35-45 minutes.
Preferably, according to the molding method of the present invention, the heating condition of the female mold 7 may be: the heating temperature is 270-280 ℃, and the heating time is 38-42 minutes; the heating condition of the male die 8 can be as follows: the heating temperature is 190-210 ℃, and the heating time is 38-42 minutes; the heating condition of the blank holder 9 can be as follows: the heating temperature is 270-280 ℃, and the heating time is 38-42 minutes.
According to the molding method of the present invention, the temperature difference formed between the lower mold 2 and the upper mold 1 may be 10 to 100 ℃, preferably 15 to 80 ℃, and more preferably 20 to 40 ℃.
According to the forming method of the invention, in the step (II), the main cylinder 15 drives the upper die plate 18 to move downwards to enable the peripheral lower surface of the female die 7 to be close to but not contacted with the blank, and the blank is preheated. In the invention, the blank can be preheated outside the die, but both methods have problems that the temperature of the plate is reduced to some extent and the yield is influenced because the stretching oil is coated after the blank is preheated. The stretched oil is firstly coated and then preheated, and oil matters are remained on the die and are difficult to clean. In the invention, preferably, the high-temperature die is used for spraying the water-based drawing oil, and after water is volatilized, a lubricating film (which is different from lubricating oil) is formed on the die, so that the production takt is accelerated, the production efficiency is improved, and the cost is saved.
According to the forming method, the blank is sprayed with high-temperature drawing oil, preferably the high-temperature drawing oil is high-temperature-resistant all-mineral synthetic oil.
According to the forming method of the present invention, in the step (III), a ratio of a depth of drawing the blank to a diameter of the blank may be (0.6 to 1): 1, preferably (0.6-0.8): 1, more preferably 1: 1.
the forming method according to the present invention, wherein the magnesium alloy sheet material is not particularly limited, and for example, may be an AZ31B sheet material, and the magnesium alloy sheet material may have a shrinkage factor of 0.2 to 0.4%, preferably 0.25 to 0.28%, and more preferably 0.267%.
For the hot forming of a magnesium alloy plate (taking the material AZ31B as an example), in the traditional process, when a two-time forming process is adopted, a large amount of heating energy is consumed, the connection between the two-time forming process needs to be switched between heating and cooling twice, and due to the factors of thermal expansion and cold contraction, the matching difficulty of two sets of dies is increased rapidly, the yield of finished products is low, and the size precision of final forming is reduced. According to the invention, aiming at the characteristic of poor hot forming performance at normal temperature, when a one-step forming process is adopted, the deep drawing forming in the positive and negative directions is realized in a set of die, the relative energy consumption is low, the yield of finished products is high, and the dimensional precision of the products is good. In addition, the mold needs to be heated and controlled in temperature, the structure of the mold is more complex, the product size deviation caused by expansion with heat and contraction with cold of the mold needs to be accurately calculated, the heating arrangement and control need to be accurately designed, the forming equipment also needs to be accurately adjusted according to the process and is provided with a cooling system and auxiliary high-temperature drawing oil, so that good drawing of the product is guaranteed, and cracks are prevented.
According to the forming method, preferably, a primary drawing process is adopted, and in the forming method, a secondary drawing process can be adopted, two sets of drawing dies need to be matched, but the dimensional accuracy is reduced by adopting the secondary drawing process.
In a third aspect, the present invention provides a magnesium alloy sheet produced by the above-described method for forming a magnesium alloy sheet.
In a fourth aspect, the invention provides an application of the magnesium alloy sheet material in an automobile seat.
Specifically, the hot press formed product belongs to a seat in an automobile seat, and has the characteristics of complex structure, large overall dimension, high dimensional precision and the like, and forward and backward drawing is required. According to the characteristics of the product, the processes of blanking, deep drawing forming, blanking, local forming, shaping and the like are required. When the batch of products is less, the blanking and the blanking can adopt a three-dimensional laser cutting process, so that the investment cost of a die and equipment can be greatly saved. When the batch of products is more, a die blanking mode can be adopted, which is beneficial to realizing continuous hot forming lines and centralized management.
In addition, in the invention, the deep drawing can adopt two schemes of a one-time forming process and a two-time forming process. The traditional cold and hot forming process does not need to heat the die and the plate, and generally can select two forming processes, namely forward drawing and reverse drawing, and two sets of dies and equipment are adopted. Furthermore, in the present invention, a one-shot molding process is adopted.
The technical scheme of the invention is adopted, namely, a one-step forming process (positive and negative stretching) is adopted, the temperature of the die is accurately controlled, the coefficient of expansion with heat and contraction with cold of the die is accurately calculated, the process action of equipment is adjusted, an equipment cooling system is added, high-temperature drawing oil with excellent performance is matched, and finally a qualified drawing product is formed.
The present invention will be described in detail below by way of examples.
Example 1
This example illustrates magnesium and gold sheets prepared using the hot press forming apparatus and hot press forming method of the present invention and their application to automobile seats.
With reference to fig. 1 to 4.
Preparation work:
firstly, determining the sizes and fit gaps of the female die 7, the male die 8 and the discharging block 5 according to the fact that the shrinkage rate of the magnesium alloy sheet material after expansion with heat and contraction with cold is 0.267 percent; the blank is sprayed with high-temperature-resistant all-mineral synthetic oil.
Secondly, the preforming oil cylinder 4 drives the discharging block 5 to rise to the upper stop position, and the lower ejection cylinder 17 drives the blank holder 9 to rise to the upper stop position; and placing a blank magnesium alloy plate AZ31B on the surface of the blank holder 9; and, heat the mould, namely, heat said cavity die 7, said terrace die 8 and said binder 9; the temperature difference formed between the lower die 2 and the upper die 1 is 80 ℃.
Wherein, a heating rod is adopted for heating, the heating temperature of the female die 7 is 275 ℃, and the heating time is 40 minutes; the heating temperature of the male die 8 is 200 ℃, and the heating time is 40 minutes; the heating temperature of the blank holder 9 is 275 ℃, and the heating time is 40 minutes. And
wherein the driving speed of the preforming oil cylinder 4 is 30mm/min, and the driving pressure is 5 Mpa; the driving speed of the lower ejection cylinder 17 is 30mm/min, and the driving pressure is 5 Mpa; the driving speed of the main cylinder 15 is 30mm/min, and the driving pressure is 5 Mpa.
(II) the main cylinder 15 drives the upper template 18 to move downwards to enable the lower surface of the periphery of the female die 7 to be close to but not contacted with the blank and preheat the blank; after the preheating is finished, the female die 7 continues to descend to tightly press the blank, so that the blank is clamped in a gap between the female die 7 and the blank holder 9.
Thirdly, the preforming oil cylinder 4 drives the discharging block 5 to move downwards and draw downwards until the blank is drawn to the upper surface of the male die 8; the ratio of the depth of drawing the blank to the diameter of the blank is 1: 1.
and (IV) the main cylinder 15 continues to descend to drive the female die 7 to move downwards, and the female die 7 and the blank holder 9 clamp an external blank structure to perform flanging and deep drawing.
(V) lifting the main cylinder, ascending the blank holder and separating the product from the male die; the master cylinder continues to rise to reach the die opening state; the preforming oil cylinder drives the unloading block to move downwards and pushes out a product; and (5) receiving the product by using a tool.
The magnesium alloy plate prepared by the method has good drawing effect, no scratch on the surface and no crack on the fillet, and well utilizes the characteristic of excellent high-temperature thermal forming performance of the magnesium alloy plate.
And, the prepared magnesium alloy sheet was applied to an automobile seat, as shown in fig. 5.
The embodiment adopts a one-step forming process (positive and negative stretching), accurately calculates the coefficient of expansion with heat and contraction with cold of the die by accurately controlling the temperature of the die, adjusts the process action of equipment, increases an equipment cooling system, matches high-temperature drawing oil with excellent performance, and the magnesium alloy plate prepared as a result has good drawing effect, no scratch on the surface and no crack on the fillet. The magnesium alloy plate hot-press forming device and the magnesium alloy plate hot-press forming method can be used for hot-press forming magnesium alloy plate parts with complex structures and large sizes, are low in energy consumption and high in yield (the yield is more than or equal to 96%), and can really realize batch application.
The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, and the invention will not be further described for various possible combinations. Such simple modifications and combinations should be considered within the scope of the present disclosure as well.
Claims (23)
1. The magnesium alloy plate hot-press forming device is characterized by comprising an upper die (1), a lower die (2) and a main cylinder (15), wherein the upper die (1) is connected with an upper template (18), the lower die (2) is connected with a lower template (19), a preforming oil cylinder (4), a discharging block (5) and a concave die (7) are arranged on the upper die (1), and a convex die (8), a blank holder (9) and a lower jacking cylinder (17) are arranged on the lower die (2);
the preforming oil cylinder (4) drives the discharging block (5) to vertically lift, and the lower jacking cylinder (17) drives the blank holder (9) to vertically lift;
the master cylinder is arranged in an overhead mode, the master cylinder drives the upper template (18) to vertically lift, and then the upper template (18) drives the female die (7) to vertically lift.
2. The magnesium alloy plate hot press molding device according to claim 1, wherein a heat insulation block (14) is arranged between the preforming cylinder (4) and the discharging block (5), and a water cooling channel (13) is arranged on the preforming cylinder (4).
3. The magnesium alloy sheet hot press forming device according to claim 2, wherein the preforming cylinder (4) is provided with a sealing ring.
4. The magnesium alloy plate hot-press forming device as claimed in claim 1, wherein a heat insulation block and a water cooling channel are arranged between the upper template (18) and the lower template (19).
5. The magnesium alloy plate hot-press forming device according to claim 1, wherein the blank holder (9) is sleeved outside the bottom of the male die (8), and the female die (7) is sleeved outside the bottom of the discharging block (5).
6. The magnesium alloy plate hot-press forming device according to claim 1 or 5, wherein the female die (7), the male die (8) and the blank holder (9) are all of a circular ring structure, accommodating holes are radially formed in the circular rings of the female die (7), the male die (8) and the blank holder (9), and a heating rod and a thermocouple connected with a power supply are inserted into the accommodating holes.
7. The magnesium alloy plate hot-press forming device according to claim 1 or 5, wherein the female die (7), the male die (8) and the blank holder (9) are all of a circular ring structure, and an oil pipeline is radially arranged on the circular rings of the female die (7), the male die (8) and the blank holder (9), is provided with a temperature sensor and is connected with an external high-temperature oil heating die temperature machine.
8. The magnesium alloy sheet hot-press molding apparatus as claimed in claim 1, wherein the dimensions and fit clearance of the female die (7), the male die (8) and the discharging block (5) are determined according to the shrinkage rate of the magnesium alloy sheet to be hot-press molded after expansion with heat and contraction with cold.
9. The magnesium alloy plate hot-press forming device according to claim 1 or 5, wherein a mechanical limiting structure is arranged between the female die (7) and the blank holder (9).
10. A hot press molding method of a magnesium alloy sheet, characterized in that the hot press molding method of a magnesium alloy sheet employs the hot press molding apparatus of a magnesium alloy sheet as set forth in any one of claims 1 to 9, and the hot press molding method of a magnesium alloy sheet comprises the steps of:
(I) the preforming oil cylinder (4) drives the discharging block (5) to ascend to an upper stop position, and the lower jacking cylinder (17) drives the blank holder (9) to ascend to the upper stop position; and placing the blank on the surface of the blank holder (9);
(II) the main cylinder (15) drives the upper template (18) to move downwards to enable the peripheral lower surface of the female die (7) to be close to but not contacted with the blank and preheat the blank; after the preheating is finished, the female die (7) continues to descend to tightly press the blank, so that the blank is clamped in a gap between the female die (7) and the blank holder (9);
(III) the preforming oil cylinder (4) drives the discharging block (5) to move downwards, and the blank is drawn downwards until the blank is drawn to the upper surface of the male die (8);
(IV) the main cylinder (15) continues to descend to drive the female die (7) to descend, and the female die (7) and the blank holder (9) clamp an external blank structure to perform flanging and deep drawing; and opening the mold and pushing out the magnesium alloy plate subjected to hot press molding.
11. The molding method according to claim 10, wherein the driving speed of the preforming cylinder (4) is 10 to 60mm/min, and the driving pressure is 1 to 12 MPa; the driving speed of the lower jacking cylinder (17) is 10-60mm/min, and the driving pressure is 1-12 MPa; the driving speed of the main cylinder (15) is 10-60mm/min, and the driving pressure is 1-12 MPa.
12. The molding method according to claim 11, wherein the driving speed of the preforming cylinder (4) is 20-50mm/min, and the driving pressure is 2-8 MPa; the driving speed of the lower jacking cylinder (17) is 20-50mm/min, and the driving pressure is 2-8 MPa; the driving speed of the main cylinder (15) is 20-50mm/min, and the driving pressure is 2-8 MPa.
13. The molding method according to claim 10, wherein in step (I), further comprising heating the female mold (7), the male mold (8) and the binder ring (9), wherein:
the heating condition of the female die (7) is as follows: the heating temperature is 260 ℃ and 300 ℃, and the heating time is 35-45 minutes; the heating condition of the male die (8) is as follows: the heating temperature is 180 ℃ and 220 ℃, and the heating time is 35-45 minutes; the heating condition of the blank holder (9) is as follows: the heating temperature is 260 ℃ to 300 ℃, and the heating time is 35-45 minutes.
14. The molding method according to claim 13, wherein the heating condition of the female mold (7) is: the heating temperature is 270-280 ℃, and the heating time is 38-42 minutes; the heating condition of the male die (8) is as follows: the heating temperature is 190-210 ℃, and the heating time is 38-42 minutes; the heating condition of the blank holder (9) is as follows: the heating temperature is 270-280 ℃, and the heating time is 38-42 minutes.
15. The molding method according to claim 10, wherein the temperature difference formed between the lower mold (2) and the upper mold (1) is 10-100 ℃.
16. The molding method according to claim 15, wherein the temperature difference formed between the lower mold (2) and the upper mold (1) is 15-80 ℃.
17. The molding method according to claim 16, wherein the temperature difference formed between the lower mold (2) and the upper mold (1) is 20-40 ℃.
18. The forming method according to claim 10, wherein the blank is sprayed with high temperature drawing oil.
19. The forming method of claim 18 wherein the high temperature drawing oil is a high temperature resistant all mineral synthetic oil.
20. The forming method according to claim 10, wherein, in step (III), a ratio of a depth of drawing of the blank to a diameter of the blank is (0.6-1): 1.
21. the molding method according to claim 10, wherein the magnesium alloy sheet is an AZ31B sheet, and the magnesium alloy sheet has a shrinkage rate of 0.2% to 0.4% when subjected to thermal expansion and contraction.
22. A magnesium alloy sheet produced by the method for forming a magnesium alloy sheet according to any one of claims 10 to 21.
23. Use of the magnesium alloy sheet according to claim 22 in an automobile seat.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711193977.XA CN109834181B (en) | 2017-11-24 | 2017-11-24 | Hot-press forming device and hot-press forming method for magnesium alloy plate, magnesium alloy plate and application of magnesium alloy plate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711193977.XA CN109834181B (en) | 2017-11-24 | 2017-11-24 | Hot-press forming device and hot-press forming method for magnesium alloy plate, magnesium alloy plate and application of magnesium alloy plate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109834181A CN109834181A (en) | 2019-06-04 |
| CN109834181B true CN109834181B (en) | 2020-10-23 |
Family
ID=66877465
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711193977.XA Active CN109834181B (en) | 2017-11-24 | 2017-11-24 | Hot-press forming device and hot-press forming method for magnesium alloy plate, magnesium alloy plate and application of magnesium alloy plate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109834181B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111804815B (en) * | 2020-07-06 | 2024-09-17 | 长春工业大学 | Horizontal rivetless connection and shaping device based on local resistance heating mode |
| CN112453201A (en) * | 2020-10-30 | 2021-03-09 | 重庆至信实业集团有限公司 | Processing technology based on taillight flume assembly |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1903473A (en) * | 2005-07-29 | 2007-01-31 | 中国科学院金属研究所 | Mild hot formation method for making magnesium alloy shell of cell phone and mould specially for the same |
| FR2902356A1 (en) * | 2006-06-15 | 2007-12-21 | Peugeot Citroen Automobiles Sa | Warm pressing a blank having alloy of aluminum and magnesium, comprises disposing the blank in tool, clutching the blank between matrix and tight enclosure, heating the blank by integrated unit, and maintaining the blank at a temperature |
| JP2012148282A (en) * | 2011-01-14 | 2012-08-09 | Kobe Steel Ltd | Press forming method for high strength steel plate |
| CN104289591A (en) * | 2014-09-29 | 2015-01-21 | 佛山市康思达液压机械有限公司 | Hydraulic device for aluminum alloy drawing and extrusion compound forming |
| CN106077257A (en) * | 2016-07-07 | 2016-11-09 | 郝鑫颖 | Almag wheel hub moulding process and equipment |
| KR20170064275A (en) * | 2015-12-01 | 2017-06-09 | 주식회사 성우하이텍 | Device for Multi forming |
| CN208288788U (en) * | 2017-11-24 | 2018-12-28 | 惠州比亚迪电子有限公司 | Magnesium alloy plate heat pressing forming device |
-
2017
- 2017-11-24 CN CN201711193977.XA patent/CN109834181B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1903473A (en) * | 2005-07-29 | 2007-01-31 | 中国科学院金属研究所 | Mild hot formation method for making magnesium alloy shell of cell phone and mould specially for the same |
| FR2902356A1 (en) * | 2006-06-15 | 2007-12-21 | Peugeot Citroen Automobiles Sa | Warm pressing a blank having alloy of aluminum and magnesium, comprises disposing the blank in tool, clutching the blank between matrix and tight enclosure, heating the blank by integrated unit, and maintaining the blank at a temperature |
| JP2012148282A (en) * | 2011-01-14 | 2012-08-09 | Kobe Steel Ltd | Press forming method for high strength steel plate |
| CN104289591A (en) * | 2014-09-29 | 2015-01-21 | 佛山市康思达液压机械有限公司 | Hydraulic device for aluminum alloy drawing and extrusion compound forming |
| KR20170064275A (en) * | 2015-12-01 | 2017-06-09 | 주식회사 성우하이텍 | Device for Multi forming |
| CN106077257A (en) * | 2016-07-07 | 2016-11-09 | 郝鑫颖 | Almag wheel hub moulding process and equipment |
| CN208288788U (en) * | 2017-11-24 | 2018-12-28 | 惠州比亚迪电子有限公司 | Magnesium alloy plate heat pressing forming device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109834181A (en) | 2019-06-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111842637B (en) | Composite forming die and forming method for titanium alloy deep cavity component | |
| CN102699094B (en) | Die used in extrusion moulding of high-precision complex copper alloy thrust bearing seat | |
| CN101209478A (en) | Sheet material non-isothermal punching forming device | |
| CN100425366C (en) | Integral extrusion forming method for asymmetrical assembly parts and apparatus thereof | |
| CN102554040A (en) | Magnesium alloy sheet different temperature drawing mold | |
| CN101015841A (en) | Warm static liquid extrusion method and mould for producing magnesium alloy wire or bar | |
| CN103381441A (en) | Hot stamping formation processing method for thin-walled titanium alloy sealing head | |
| CN109834181B (en) | Hot-press forming device and hot-press forming method for magnesium alloy plate, magnesium alloy plate and application of magnesium alloy plate | |
| CN103736894A (en) | Isothermal forging die and forging technology thereof of magnesium alloy die forge piece of step type structure | |
| CN101328930A (en) | Cold-extruded machining process of diesel starting shaft | |
| CN101850396B (en) | Two-stage press forging and forming method of metal thin shell piece with inward convex micro-structure | |
| CN105057529A (en) | Extrusion forming method for hollow shaft forged piece with variable cross section | |
| CN104550403A (en) | Device and process for realizing high-temperature barometric bulging of hollow metal component | |
| CN101823113A (en) | Method and die carrier for forging and molding special-shaped cross section metal blank with through holes | |
| CN104148889B (en) | A kind of square plate casing blank manufacturing process and mated forming die thereof | |
| CN204817867U (en) | Cold extruding die | |
| CN101774006A (en) | Four-post vertical hydraulic equipment used for liquid metal casting and forging molding | |
| CN105107946A (en) | Hot-working forming equipment and method for metal shell or plate | |
| CN208288788U (en) | Magnesium alloy plate heat pressing forming device | |
| CN109304375B (en) | Multi-male-die step-by-step backward extrusion forming method | |
| CN100386166C (en) | One-forge-to-multipiece superplastic forming device for amorphous alloy precise parts | |
| CN103753150B (en) | A kind of preparation method of magnesium alloy honeycomb blind hole structural member | |
| CN109834169B (en) | Magnesium alloy plate hot-press forming method, hot-press formed part and application thereof | |
| CN202427740U (en) | Blank forming extrusion die holder | |
| CN101234405B (en) | Forward and reverse superplastic bulging method capable of changing friction condition |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |