CN103861932B - A kind of building mortion of thermoplastic glass fiber reinforced aramid aluminiumlaminates and method - Google Patents

Abstract

The invention discloses a forming device and method for a thermoplastic glass fiber reinforced aluminum alloy laminate, wherein the device comprises a sealing ring (1), a discharge coil (3), a coil frame (4), and bolts (5, 11) , the lower platen (6), the base (7), the resistance wire (9), the upper platen (10), the hydraulic cylinder (12), wherein the bolts (5, 11) and the bottom of the upper platen (10) are welded connection, the hydraulic cylinder (12) is fixed on the upper platen (10), the working arm of the hydraulic cylinder (12) extends downward through the center hole of the upper platen (10), and the lower end of the working arm of the hydraulic cylinder (12) is in contact with the seal The blank holder (1) is fixedly connected, and a travel limit block (13) is welded on the working arm; an air vent (8) is opened on the side wall of the sealing blank holder (1); this device can Preheating is carried out and the cooling rate when the laminate is cooled can be controlled, so as to release the residual thermal stress caused by the difference in shrinkage of the plate and prevent cracking between layers.

Description

A forming device and method for a thermoplastic glass fiber reinforced aluminum alloy laminate

technical field

The invention belongs to the field of processing and forming of metal matrix composite materials, and in particular relates to a forming method of a thermoplastic glass fiber reinforced aluminum alloy laminate.

Background technique

Fiber Reinforced Metal Laminates (FRML) is a special metal matrix composite material, which is alternately laminated by metal alloy sheets and fiber/resin layups by bonding technology. Fiber laminates have excellent comprehensive properties, and glass fiber reinforced aluminum alloy laminates are currently the most used one. It not only has the advantages of high specific strength, specific stiffness, good plasticity, fracture performance and impact resistance of metal materials, but also retains the good fatigue resistance of fiber reinforced materials, and its quality is relatively light, which meets the future lightweight requirements. Direction of development. In addition, fiber-reinforced metal laminates also have good sound insulation and noise absorption capabilities, which can effectively reduce noise and improve comfort when used in the automotive industry. Glass fiber reinforced thermoplastic (GMT) material is a composite material with thermoplastic resin as the matrix and glass fiber mat as the reinforced skeleton. Generally, semi-finished sheets can be produced, and then directly processed into products of the required shape. Thermoplastic glass fiber plastic can be used as a reinforcing base for metal laminates, and thermoplastic fiber reinforced metal laminates (FML) have better impact properties than thermoset laminates (FML). However, due to the traditional forming process such as lamination process, there are many steps in the forming process, large investment and low efficiency, so it is not suitable for mass production. Therefore, some scholars have introduced stamping technology into the forming of composite materials, but there are still some problems. At room temperature, the plasticity of the fiber-reinforced layer is relatively poor, and it is prone to brittle failure and other failures when it is formed by stamping, resulting in processing difficulties; when stamping at elevated temperatures, the rebound of the plate will be more obvious. Therefore, fiber-reinforced metal laminates with superior performance are only used in high-tech fields such as aerospace and military industry.

Electromagnetic forming is a high-rate forming technique that uses magnetic field forces to deform metal blanks. Because of the high energy density characteristics of electromagnetic forming technology, the workpiece shows superplasticity of explosive forming when it is deformed. Therefore, it can significantly improve the forming limit of the metal, and the metal in the formed part is evenly stressed, and the forming defects such as cracking are not easy to occur. The high strain rate characteristics can make the metal mold fast, and the springback of the metal is generally small or even non-rebound. Therefore, using electromagnetic forming technology to form thermoplastic glass fiber reinforced metal laminates and properly preheating can effectively improve the formability of fiber reinforced metal laminates, solve the problem of brittle failure in the existing forming technology, and can effectively avoid recycling. Elastic, improve the dimensional accuracy of sheet metal forming. This forming method can also easily complete operations such as round hole flanging and special-shaped hole flanging, which effectively improves the assembly performance of the material. For example, the invention patent application number is 201310355871.0, although the forming method of a titanium alloy thin-walled shell solves the springback problem when forming a thin plate, it cannot preheat the plate without a heating device and is not suitable for thermoplastic glass fiber reinforced aluminum alloys. Processing of laminates; such as the invention patent application number of 200910062979.4, the magnesium alloy plate warm forming method can improve the formability of the material, but the heating efficiency is low and the cooling rate cannot be controlled uniformly, so when processing thermoplastic glass fiber reinforced aluminum alloy Laminates can lead to processing defects and cracking between layers.

Contents of the invention

The purpose of the present invention is to provide a thermoplastic glass fiber reinforced aluminum alloy laminate forming device and method for the forming of thermoplastic glass fiber reinforced aluminum alloy laminates, aiming at the deficiencies in the prior art.

The technical solution of the present invention is to provide a forming device for thermoplastic glass fiber reinforced aluminum alloy laminates, which is characterized in that it includes a sealing blank holder, a discharge coil, a coil frame, bolts, a lower pressing plate, a base, a resistance wire, an upper pressing plate, The hydraulic cylinder, wherein the bolts and the bottom of the upper platen are connected by welding, the hydraulic cylinder is fixed on the upper platen with bolts, the working arm of the hydraulic cylinder extends downward through the center hole of the upper platen, and the working arm of the hydraulic cylinder The lower end is fixedly connected with the sealing blank holder, and a stroke limit block is welded on the working arm; there is a vent hole on the side wall of the sealing blank holder;

The base is fixed in the circular groove of the lower platen. In order to ensure the connection strength, a layer of adhesive can be coated in the groove, which is also convenient for disassembly and assembly in the future; the groove depth of the sealing edge ring is larger than that of thermoplastic glass fiber reinforced The deformation thickness of the aluminum alloy laminate plays a dual role of sealing heating and edge pressing;

After the thermoplastic glass fiber reinforced aluminum alloy laminate is positioned, turn on the power, and use the resistance wire to heat the thermoplastic glass fiber reinforced aluminum alloy laminate until the temperature stabilizes at the preset temperature;

The energy storage capacitor of the forming device is charged, and when the voltage of the energy storage capacitor reaches the forming voltage, the discharge coil is discharged, and the thermoplastic glass fiber reinforced aluminum alloy laminate is deformed under the action of the electromagnetic force generated by the discharge coil.

Further, the present invention also provides a material forming method using a forming device for thermoplastic glass fiber reinforced aluminum alloy laminates, which is characterized in that:

Step 1. Fix the thermoplastic glass fiber reinforced aluminum alloy laminate on the base, then place the sealing edge ring in the groove of the base, and apply appropriate pressure to the sealing edge ring with a hydraulic cylinder to seal the thermoplastic glass fiber reinforcement. Aluminum alloy laminate produces proper blank-holding force;

Step 2, energize the resistance wire in the sealing edge ring, and uniformly heat the thermoplastic glass fiber reinforced aluminum alloy laminate;

Step 3. Heat the thermoplastic glass fiber reinforced aluminum alloy laminate for a preset time and temperature. After heating to the preset temperature, heat the thermoplastic glass fiber reinforced aluminum alloy laminate for a certain period of time to make each part heated evenly ;

Step 4. Charge the energy storage capacitor of the electromagnetic forming equipment, and disconnect the charging circuit when the charging voltage reaches the set forming voltage of 2-15Kv;

Step 5, closing the electromagnetic forming discharge circuit, the energy storage capacitor discharges the electromagnetic forming coil, and the thermoplastic glass fiber reinforced aluminum alloy laminate is rapidly deformed under the action of electromagnetic force;

Step 6. After the deformation of the thermoplastic glass fiber reinforced aluminum alloy laminate is completed, the cooling rate should be controlled to eliminate the residual thermal stress caused by the different shrinkage rates of the materials of each layer during the cooling process;

Step 7. After the cooling process is completed, locally heat the free edge, and then cool under a sufficiently high pressure to prevent debonding between layers.

Further, in step 1, the thermoplastic glass fiber reinforced aluminum alloy laminate to be formed is pressed against the electromagnetic forming coil through the action of the upper and lower pressing plates, and the discharge coil and its coil frame are well fixed.

Further, in step 2, two exhaust holes are provided on the side of the sealing binder ring to ensure that the gas in the sealing binder ring can be discharged and heat exchange with the outside during the cooling process.

Further, in step 2, a thermocouple is used to detect the heating temperature of the thermoplastic glass fiber reinforced aluminum alloy laminate, and the temperature is stabilized within a preset range.

Further, in step 5, the electromagnetic forming coil and the coil skeleton are solidified together through insulating resin, and have good insulation properties with the thermoplastic glass fiber reinforced aluminum alloy laminate.

Further, the thickness of the thermoplastic glass fiber reinforced aluminum alloy laminate is 0.7-4mm.

Compared with the existing thermoplastic glass fiber reinforced aluminum alloy laminate forming technology, this technology has the following advantages:

1. The high-speed forming characteristics of electromagnetic forming can reduce the shear force between layers during the forming process, thereby reducing the cracking between layers and improving the transverse stiffness of the laminate.

2. The high-speed forming characteristics of electromagnetic forming can solve the problem of large springback during preheating stamping and have higher shape and position accuracy than stamping forming.

3. During the forming process, the laminate needs to be heated and electromagnetic pressure is applied. It belongs to the secondary hot pressing, which can enhance the impregnation of the glass fiber bundles of the glass fiber plastic layer and the bonding between layers, thereby enhancing the shear performance of the laminate. The mechanical properties of the laminate are improved.

4. The curing exothermic reaction is not included in the electromagnetic forming process, which can greatly shorten the forming cycle, greatly improve the production efficiency, and is more suitable for mass production.

5. In addition to preheating the laminates, the sealing ring can also control the cooling rate of the laminates when they are cooled, so as to fully release the residual thermal stress caused by the different shrinkage rates between the layers of the board to prevent cracking between the layers .

6. Electro-hydraulic forming can effectively increase the forming limit of laminates, thereby forming plates with more complex shapes and higher precision, and making laminates have a wider range of application.

Description of drawings

Figure 1 shows the overall schematic diagram of the electromagnetic forming device

Figure 2 shows the front view and top view of the upper platen;

Figure 3 shows the front view and top view of the lower platen;

Figure 4 shows the front view and top view of the sealing blank holder;

Figure 5 shows the front view and top view of the base;

Figure 6 shows the front view and top view of the outer groove;

Fig. 7 shows the front view and top view of the thermoplastic glass fiber reinforced aluminum alloy laminate in Example 1;

Fig. 8 shows the front view and top view of the thermoplastic glass fiber reinforced aluminum alloy laminate in Example 2;

Fig. 9 shows the overall schematic diagram of the flanging forming device of embodiment 2;

Figure 10 shows the flanging mold of embodiment 2;

Fig. 11 is a cross-sectional view of the thermoplastic glass fiber reinforced aluminum alloy laminate in Example 2 after flanging.

in:

Explanation of the marks in attached drawing 1:

1--Sealing edge ring; 2--Thermoplastic glass fiber reinforced aluminum alloy laminate; 3--Discharge coil;

4--coil frame; 5, 11--bolts; 6--lower pressure plate; 7--base; 8--exhaust hole; 9 resistance wire;

10--upper platen; 12 hydraulic cylinder; 13 travel limit block;

Explanation of the marks in accompanying drawing 9:

1--Sealing edge ring; 2--Thermoplastic glass fiber reinforced aluminum alloy laminate; 3--Discharge coil;

4--coil frame; 5, 11--bolts; 6--lower pressure plate; 7--base; 8--exhaust hole; 9 resistance wire;

10--upper platen; 12 hydraulic cylinder; 13 travel limit block; 14 flanging mould.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments. Apparently, the described embodiments are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The study found that compared with the traditional electromagnetic forming technology, there are special requirements on the process parameters when processing thermoplastic glass fiber reinforced aluminum alloy laminates. For example, if the time of heat preservation during processing, the temperature of heat preservation, the cooling rate, and the parameters of the mold are not selected properly, it will cause defects such as wrinkling of the laminate, cracking between layers, and fiber bending, which will affect the performance of the laminate. Therefore, many influencing factors should be considered in the selection of mold materials. The first is the thermal expansion coefficient of the mold. If the thermal expansion coefficient of the mold is too large, a large compressive stress will be generated on the contact surface with the laminate, thereby affecting the stress distribution in the thickness direction of the laminate; secondly, the thermal conductivity of the mold, thermal conductivity A small rate will cause a large temperature gradient difference in the thickness direction of the laminate during heating and cooling, resulting in a large residual thermal stress; finally, the influence of the friction coefficient of the mold must also be considered. If the friction coefficient of the mold is too large, the laminate When thermal expansion is subjected to greater resistance, it will be forced to shrink, resulting in greater residual stress. Therefore, a graphite mold with a smaller thermal expansion coefficient, better thermal conductivity and better lubrication is finally selected. For the cooling rate, if the cooling rate is too fast and the thickness of the laminate is large, the temperature gradient in the thickness direction will be too large, resulting in defects such as interlayer cracking and deformation; if the temperature is too small, it will affect the efficiency of production. And also will control heat preservation time and heat preservation temperature when heating. Therefore, the device has better temperature control performance and can meet the needs of different temperature control.

As shown in Figure 1, a forming device for a thermoplastic glass fiber reinforced aluminum alloy laminate according to the present invention includes a rectifier, a capacitor, a current limiting resistor, a discharge coil, a switch, a sealing binder ring and a sealing binder ring fixing device etc., wherein the resistance wire of the resistance heating box is fixed directly above the thermoplastic glass fiber reinforced aluminum alloy laminate to improve the heating efficiency and make the heating more uniform. The biggest difference between this device and other devices is that it can accurately control the heating temperature and cooling temperature. Because thermoplastic glass fiber reinforced aluminum alloy laminates must be preheated before forming and the rate of cooling must be controlled to prevent cracking between layers.

The thermoplastic glass fiber reinforced aluminum alloy laminate used in the embodiment of the present invention has a diameter of 30 cm and a thickness of 2 mm. The aluminum alloy laminate material is 2024-T3, and the thickness is about 0.5mm; the matrix of glass fiber reinforced plastic is thermoplastic resin polypropylene, and the thickness of the adhesive layer and glass fiber reinforced plastic layer is about 0.2mm.

As shown in Fig. 1, in the first embodiment, the forming device of the thermoplastic glass fiber reinforced aluminum alloy laminate comprises a graphite sealing blank holder 1, a discharge coil 3, a coil frame 4, bolts 5, 11, a lower pressing plate 6, Graphite base 7, resistance wire 9, upper platen 10, hydraulic cylinder 12, etc. Wherein, bolts 5, 11 and the bottom of upper pressing plate 10 are connected by welding, hydraulic cylinder 12 is fixed on upper pressing plate 10, the working arm of hydraulic cylinder 12 passes through the central hole of upper pressing plate 10, and the working arm of hydraulic cylinder 12 The lower end is threadedly connected with the sealing bead ring 1, and a travel limit block 13 is welded on the working arm to ensure the relative position of the sealing bead ring 1 and the upper platen 10. When a force acts on the sealing bead ring, a The reaction force is borne by the four bolts fixing the upper and lower pressure plates;

The graphite base 7 is fixed in the circular groove of the lower platen 6, and a layer of adhesive can be applied in the groove to ensure the connection strength, which is also convenient for later disassembly and assembly. The groove depth of the sealing blank holder 1 is much larger than the possible deformation thickness of the thermoplastic glass fiber reinforced aluminum alloy laminate 2, so as to play dual functions of sealing heating and blank clamping.

In addition, there is an exhaust hole 8 on the side wall of the sealing blank holder 1. The exhaust hole 8 prevents the air pressure in the cavity from being too high during the rapid forming process, which hinders the forming; It comes to exchange heat with the outside to control the cooling temperature.

As shown in Figure 1, the base 7 is positioned in the circular groove on the lower pressure plate 6, the thermoplastic glass fiber reinforced aluminum alloy laminate 2 with a thickness of 2mm is placed in the positioning groove of the base 7, and then the sealing pressure The edge ring 1 is placed on the thermoplastic glass fiber reinforced aluminum alloy laminate 2, and a hydraulic cylinder 12 is used to apply appropriate pressure to the sealing edge ring 1, so that the sealing edge ring 1 is on the thermoplastic glass fiber reinforced aluminum alloy layer 2. A blank-holding force of 3MPa is produced.

After completing the fixing and positioning of the thermoplastic glass fiber reinforced aluminum alloy laminate 2, turn on the power, and use the resistance wire 9 to heat the thermoplastic glass fiber reinforced aluminum alloy laminate 2 until the temperature stabilizes at about 160°C. Fiber-reinforced polypropylene plastic laminates will have a better softening effect at this temperature, and the interlayer shear force will be significantly smaller, which greatly improves the formability. After heating to 160°C, keep warm at this temperature for 10 minutes to heat the thermoplastic glass fiber reinforced aluminum alloy laminate evenly. At the same time, the energy storage capacitor of the electromagnetic forming equipment is charged, and when the charging voltage reaches the forming voltage of 2KV, the discharge coil 3 is discharged, and the thermoplastic glass fiber reinforced aluminum alloy laminate 2 acts on the electromagnetic force generated by the discharge coil 3 Deformation occurs rapidly.

Do not remove the sealing ring 1 immediately after deformation, use the resistance wire to heat properly and conduct heat exchange with the outside through the vent hole to cool the temperature inside the sealing ring to room temperature at a uniform speed within 5 minutes, so as to release the cooling process. The residual thermal stress prevents cracking between layers of thermoplastic glass fiber reinforced aluminum alloy laminates. When the temperature in the sealing blank holder 1 drops to room temperature, the bulging of the thermoplastic glass fiber reinforced aluminum alloy laminate is completed. The thermoplastic glass fiber-reinforced aluminum alloy laminate 2 is then treated with localized heat. The specific method is as follows: locally heat the free edge of the thermoplastic glass fiber reinforced aluminum alloy laminate 2 to 160 degrees Celsius, and then cool it under a pressure of 3 MPa for 2 minutes to prevent interlayer bonding.

The second embodiment of the present invention is flanging the thermoplastic glass fiber reinforced aluminum alloy laminate.

In this embodiment, the thermoplastic glass fiber reinforced aluminum alloy laminate used is 2024-T3, with a diameter of 30 cm and a thickness of 2 mm. A circular hole with a diameter of 8 cm is opened in the center of the laminate, and the glass fiber The plastic matrix is thermoplastic polypropylene, the thickness of the aluminum alloy layer is about 0.5mm, and the thickness of the adhesive layer and the glass fiber reinforced layer is about 0.2mm.

As shown in Figure 9, the electromagnetic forming device used in this embodiment consists of a sealing blank holder 1, a discharge coil 3, a bobbin 4, bolts 5, 11, a lower pressing plate 6, a base 7, a resistance wire 9, an upper pressing plate 10, Hydraulic cylinder 12, stroke limit block 13, flanging mold 14, etc.

In addition, in this embodiment, the shape of the thermoplastic glass fiber reinforced aluminum alloy laminate used is shown in Figure 8, and the base 7 is positioned in the circular groove on the lower pressing plate 6, and a layer of adhesive can be applied to ensure the connection strength. Place the thermoplastic glass fiber reinforced aluminum alloy laminate 2 with a thickness of 2 mm in the positioning groove of the base 7, then place the sealing blank holder 1 on the thermoplastic glass fiber reinforced aluminum alloy laminate 2, and use hydraulic The cylinder 12 exerts an appropriate pressure on the sealing blank holder 1 so that the sealing blank holder 1 produces a blank holding force of 3 MPa on the thermoplastic glass fiber reinforced aluminum alloy laminate 2 . After completing the fixing and positioning of the thermoplastic glass fiber reinforced aluminum alloy laminate 2, turn on the power, and use the resistance wire 9 to partially heat the thermoplastic glass fiber reinforced aluminum alloy laminate 2 through the central hole of the mold 13 until the cavity is sealed. The internal temperature is stable at about 160°C. Studies have shown that at this temperature, the glass fiber reinforced polypropylene plastic laminate will have a better softening effect, and the interlayer shear force will be significantly smaller, which greatly improves the formability. After heating to 160°C, keep warm at this temperature for 10 minutes to heat the thermoplastic glass fiber reinforced aluminum alloy laminate evenly. Among them, the central round hole of the flanging mold is provided with rounded corners to facilitate the forming of thermoplastic glass fiber reinforced aluminum alloy laminates. At the same time, the energy storage capacitor of the electromagnetic forming equipment is charged, and when the charging voltage reaches the forming voltage of 2KV, the discharge coil 3 is discharged, and the thermoplastic glass fiber reinforced aluminum alloy laminate 2 acts on the electromagnetic force generated by the discharge coil 3 Make the material stick to the mold quickly. Do not remove the sealing ring immediately after deformation. Use the resistance wire to heat properly and conduct heat exchange through the vent hole and the outside to cool the temperature inside the sealing ring to room temperature within 5 minutes. , to release the residual thermal stress during cooling and prevent cracking between laminates. When the temperature in the sealing blankholder is reduced to room temperature, the forming of the thermoplastic glass fiber reinforced aluminum alloy laminate is completed. The shape of the thermoplastic glass fiber reinforced aluminum alloy laminate after forming is shown in Figure 11. The free edge is locally heated to 160 degrees Celsius, and then cooled under a pressure of 3Mpa for 2 minutes to prevent the opening of the layers.

In summary, the electromagnetic forming method of thermoplastic glass fiber reinforced aluminum alloy laminates according to the present invention specifically includes the following steps:

Step 1. Fix the thermoplastic glass fiber reinforced aluminum alloy laminate on the base 7, then place the sealing binder ring 1 in the groove of the base, and apply appropriate pressure to the sealing binder ring 1 with the hydraulic cylinder 12 to The thermoplastic glass fiber reinforced aluminum alloy laminate 2 produces proper blank-holding force.

Among them, the hydraulic cylinder 12 is fixed on the upper platen 10 with bolts, and the reaction force generated when the force acts on the sealing flange 1 is borne by the bolts fixing the upper platen;

In this step, the function of the upper and lower pressing plates is to press the thermoplastic glass fiber reinforced aluminum alloy laminate 2 to be formed against the electromagnetic forming coil 3, and ensure that the discharge coil 3 and its coil skeleton 4 are well fixed;

In this step, drawing beads are provided on the sealing blank holder ring and the base to provide sufficient blank holder force.

Step 2, energize the resistance wire 9 in the sealing edge ring 1 to increase the temperature in the mold to the softening temperature, and uniformly heat the thermoplastic glass fiber reinforced aluminum alloy laminate 2 to achieve the purpose of improving its plastic deformation performance . This is a critical step in thermoplastic fiberglass reinforced metal laminates, otherwise the formability would be very poor.

In this step, vent holes 8 are provided on the side of the sealing binder ring to ensure that the gas in the sealing binder ring can be discharged, so as not to hinder the forming of the thermoplastic glass fiber reinforced aluminum alloy laminate.

In this step, the temperature rise of the thermoplastic glass fiber reinforced aluminum alloy laminate is detected by a thermocouple, and the temperature is stabilized within a preset range.

In this step, the overall shape of the resistance wire is circular and placed directly above the thermoplastic glass fiber reinforced aluminum alloy laminate, so as to improve the heating efficiency and make the heating more uniform.

Step 3, heat preservation of the thermoplastic glass fiber reinforced aluminum alloy laminate for a preset time and temperature. After heating to 160°C, the laminate should be kept warm so that all parts can be heated evenly.

Step 4. Charge the energy storage capacitor of the electromagnetic forming equipment, and disconnect the charging circuit when the charging voltage reaches the set forming voltage of 2-15Kv;

In this step, the discharge voltage is estimated according to the thickness of the thermoplastic glass fiber reinforced aluminum alloy laminate, and corresponding tests are carried out to determine the optimal discharge voltage during forming.

Step 5, closing the electromagnetic forming discharge circuit, the energy storage capacitor discharges the electromagnetic forming coil, and the thermoplastic glass fiber reinforced aluminum alloy laminate undergoes high-speed deformation under the action of electromagnetic force.

In this step, the electromagnetic forming process is as follows: by closing the circuit switch, the capacitor is discharged, and the strong current generated by the discharge passes through the coil to generate an induced magnetic field around it, and at the same time, an induced current is generated in the workpiece, and the induced current is generated in the thermoplastic glass. An induced magnetic field is generated around the fiber reinforced aluminum alloy laminate, and the induced magnetic field generated by the thermoplastic glass fiber reinforced aluminum alloy laminate and the magnetic field force of the induced magnetic field generated by the coil repel each other, and the thermoplastic glass fiber reinforced aluminum alloy laminate is under the action of a strong electromagnetic force Under plastic deformation.

In addition, in the electromagnetic forming process, the aluminum alloy laminate acts as a driving piece, applying a driving force to the glass fiber laminate with relatively poor conductivity, so that the laminate is plastically deformed under the action of electromagnetic force.

In this step, the electromagnetic forming coil 3 and the coil bobbin 4 are cured together through high-strength insulating resin and the thermoplastic glass fiber reinforced aluminum alloy laminate has good insulation.

Step 6. After the deformation of the thermoplastic glass fiber-reinforced aluminum alloy laminate is completed, the cooling rate is controlled to eliminate the residual thermal stress caused by the different shrinkage rates of the materials of each layer during the cooling process.

The specific method is to use a thermocouple to sense the temperature, and then control the heating speed of the resistance wire and the flow of air through a temperature controller to achieve the purpose of controlling the cooling rate. In the forming process of the laminate, the temperature control has a crucial influence on the quality and performance of the laminate, so temperature control is quite critical.

Step 7. After the electromagnetic forming is completed, the free edge is locally heated, and then cooled under a sufficiently high pressure to prevent debonding between layers.

The free boundary effect refers to the phenomenon that there is a large interlaminar stress concentration at the free boundary of the composite laminate due to the difference in the Poisson coupling coefficient or the tensile-shear coupling coefficient of each single-layer plate.

Because there is a free edge effect on the sectional side of the thermoplastic glass fiber reinforced aluminum alloy laminate, local heating is required during the cooling process to improve the performance of the thermoplastic glass fiber reinforced aluminum alloy laminate.

In the present invention, the thickness of the thermoplastic glass fiber reinforced aluminum alloy laminate is 0.7-4mm.

Claims (9)

1. the building mortion of a thermoplastic glass fiber reinforced aramid aluminiumlaminates, it is characterized in that: comprise sealing pressing flange (1), discharge coil (3), coil rack (4), bolt (5, 11), lower platen (6), base (7), resistance wire (9), top board (10), hydraulic cylinder (12), wherein, bolt (5, 11) mode of welding is adopted to be connected with the bottom of top board (10), hydraulic cylinder (12) is fixed on top board (10), the working arm of hydraulic cylinder (12) passes the centre bore of top board (10) to downward-extension, working arm lower end and the sealing pressing flange (1) of hydraulic cylinder (12) are connected, and working arm is welded with stroke limit block (13), the sidewall of sealing pressing flange (1) has steam vent (8),

Base (7) is fixed on lower platen (6); Described sealing pressing flange (1) has groove;

After thermoplastic glass fiber reinforced aramid aluminiumlaminates (2) location, opening power, utilizes resistance wire (9) to heat, until temperature stabilization is at preset temperature thermoplastic glass fiber reinforced aramid aluminiumlaminates (2);

The storage capacitor of building mortion is charged, after storage capacitor voltage reaches shaping voltage, discharge to discharge coil (3), thermoplastic glass fiber reinforced aramid aluminiumlaminates (2) deforms under discharge coil (3) produces the effect of electromagnetic force;

Sealing pressing flange (1) is not removed after thermoplastic glass fiber reinforced aramid aluminiumlaminates (2) distortion, use resistance wire suitably to heat and carry out the method for heat exchange by steam vent (8) and the external world, making temperature in sealing pressing flange at the uniform velocity cool to room temperature in 5min.

2. the building mortion of thermoplastic glass fiber reinforced aramid aluminiumlaminates according to claim 1, it is characterized in that: be positioned in the detent of base (7) by thermoplastic glass fiber reinforced aramid aluminiumlaminates (2), sealing pressing flange (1) is placed on thermoplastic glass fiber reinforced aramid aluminiumlaminates (2).

3. the building mortion of thermoplastic glass fiber reinforced aramid aluminiumlaminates according to claim 1, it is characterized in that: when masterpiece is on sealing pressing flange, the reaction force produced is born by the bolt (5,11) fixing top board (10).

4. utilize the building mortion of thermoplastic glass fiber reinforced aramid aluminiumlaminates described in claim 1 to carry out the method for material forming, it is characterized in that:

Step 1, thermoplastic glass fiber reinforced aramid aluminiumlaminates is fixed on base (7), then sealing pressing flange (1) is placed in the groove of base, and with hydraulic cylinder (12), suitable pressure is applied to sealing pressing flange (1), to produce suitable pressure-pad-force to thermoplastic glass fiber reinforced aramid aluminiumlaminates (2);

Step 2, by sealing pressing flange (1) resistance wire (9) energising, homogeneous heating is carried out to thermoplastic glass fiber reinforced aramid aluminiumlaminates (2);

Step 3, thermoplastic glass fiber reinforced aramid aluminiumlaminates (2) is carried out to the insulation of Preset Time and temperature, after being heated to preset temperature, thermoplastic glass fiber reinforced aramid aluminiumlaminates (2) is incubated, to make each several part homogeneous heating;

Step 4, the storage capacitor of electro-magnetic forming equipment to be charged, after charging voltage reaches the shaping voltage 2-15Kv of setting, disconnect charge circuit;

Step 5, closed electromagnetic shaping discharge loop, storage capacitor discharges to discharge coil (3), and thermoplastic glass fiber reinforced aramid aluminiumlaminates (2), under the effect of electromagnetic force, high-speed deformation occurs;

Step 6, after thermoplastic glass fiber reinforced aramid aluminiumlaminates (2) completes distortion, controlled cooling model speed with eliminate in cooling procedure due to layers of material shrinkage factor difference produce residual thermal stress;

Step 7, after electro-magnetic forming completes, carry out local heat, cool at high enough pressure subsequently free margins place, opening between preventing layer is sticky.

5. method according to claim 4, it is characterized in that: in step 1, by the effect of upper lower platen, thermoplastic glass fiber reinforced aramid aluminiumlaminates (2) to be formed is pressed against on discharge coil (3), and ensures that discharge coil (3) and coil rack (4) thereof are fixed well.

6. method according to claim 4, is characterized in that: in step 2, and described sealing pressing flange (1) side is provided with steam vent (8), to guarantee that the gas in sealing pressing flange can be discharged in time.

7. method according to claim 4, is characterized in that: in step 2, the warming temperature of the thermoplastic glass fiber reinforced aramid aluminiumlaminates (2) described in use thermocouple detects, and makes temperature stabilization in preset range.

8. method according to claim 4, it is characterized in that: in steps of 5, described discharge coil (3) and coil rack (4) are solidified togather through insulating resin, and have good insulating properties with thermoplastic glass fiber reinforced aramid aluminiumlaminates.

9. method according to claim 4, is characterized in that: in step 1, and the thickness of thermoplastic glass fiber reinforced aramid aluminiumlaminates (2) is 0.7 ~ 4mm.