JPH0796520A - Molding of glass base composite material - Google Patents

Abstract

PURPOSE:To enhance the toughness of a molded product and to eliminate residual voids and to enhance the limit of accuracy by a method wherein a glass base composite material is heated to be molded in a pellet shape and the molded pellets are preheated to specific temp. to be supplied into a heating cylinder and further heated to be injected in a molten state. CONSTITUTION:The pellets 41 composed of a glass base composite material received in a hopper 40 are held to the temp. range from the transition point of a glass material to the softening point thereof and heated and melted within a heating cylinder 1 while rotated by a screw 33 to be supplied to a storage part 43. When the storage part 43 is filled with the glass base composite material, the rotation of the screw 33 is stopped and the glass base composite material of an injection molding shot is cooled in a cavity 30 and, after the completion of cooling, mold opening is performed to eject a molded product by an ejector and mold clamping is again performed to start injection. That is, at the time of injection, the screw 33 is advanced to the foremost injection position by an injection cylinder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass-based composite material molding method.

[0002]

2. Description of the Related Art Conventionally, in order to have higher corrosion resistance and abrasion resistance than those made of plastic, molded products have been formed by dispersing additives such as short fibers, whiskers and particles in a glass material. In that case, the powdery glass material and the additives are mixed and filled in the cavity of the mold, and then sintered.

However, in the glass-based composite material molding method, a mixture of powdery glass material and additives is directly sintered, so that it is difficult to uniformly disperse the additives. In addition, residual pores are generated in the molded product, and the accuracy limit is lowered due to shrinkage due to sintering. Therefore, a glass-based composite material molding method has been attempted in which a melted glass material and additives are mixed and cast.

[0004]

However, in the conventional glass-based composite material molding method by casting,
There is a difference in specific gravity between the glass material and the additive, and it is difficult to uniformly disperse the additive when the glass material and the additive are mixed, and the glass material and the additive react with each other toughness ( (Finance) will be low.

The present invention solves the problems of the conventional methods for molding both glass-based composite materials, can uniformly disperse the additive, and can increase the toughness of the molded product, It is an object of the present invention to provide a glass-based composite material molding method that does not generate residual pores in a product and can increase the accuracy limit.

[0006]

Therefore, in the glass-based composite material molding method of the present invention, a glass material as a base material and additives are mixed to form a glass-based composite material, and the glass-based composite material is set. Heat to a temperature and mold into pellets. Next, the pellet-shaped glass-based composite material was heated in advance to a softening point or lower above the transition point of the glass material and then fed into a heating cylinder, and further heated and melted in the heating cylinder to be melted. Inject the glass matrix composite.

In another method of molding a glass-based composite material of the present invention, the pellet-shaped glass-based composite material is melted by mixing powdery glass materials and additives with a mixer and then melting the melted glass. It is formed by cutting the base composite material in a semi-molten state. In still another glass-based composite material molding method of the present invention, the pellet-shaped glass-based composite material is prepared by mixing powdery glass material and additives into a mold, heating and sintering. Molded.

In still another glass-based composite material molding method of the present invention, the pellet-shaped glass-based composite material is a powdery glass material and an additive at a set temperature not lower than the transition point and not higher than the softening point of the glass material. Are mixed and poured into a mold, and then heated and sintered to be molded. In still another glass-based composite material molding method of the present invention, the pellet-shaped glass-based composite material is prepared by mixing a powdery glass material and an additive at a set temperature equal to or higher than the transition point of the glass material and equal to or lower than the softening point. , Is pressed by a mold at a set temperature near the softening point.

In still another glass-based composite material molding method of the present invention, the pellet-shaped glass-based composite material is a powdery glass material and additives at a set temperature not lower than the transition point and not higher than the softening point of the glass material. Are mixed, extruded in a semi-molten state by an extruder, cut and molded.

[0010]

According to the present invention, as described above, in the glass-based composite material molding method, the glass material and the additive to be the base material are mixed to form the glass-based composite material, and the glass-based composite material is heated to the set temperature. Heat to form pellets. Next, the pellet-shaped glass-based composite material is supplied to the heating cylinder after being heated to a softening point or less above the transition point of the glass material in advance,
Further heating is performed in the heating cylinder to melt the glass-based composite material, and the melted glass-based composite material is injected.

In this case, since the additives are uniformly dispersed in the raw material stage, that is, in the state of pellets, which are minute units, unevenness is suppressed from occurring during plasticization and injection, and the additives are even within the molded product. Disperse into. Furthermore, since the glass-based composite material is immediately injected after being melted, the reaction between the glass material and the additive can be suppressed as much as possible. Therefore, it is possible to prevent deterioration of toughness, which is a problem in molding with the glass-based composite material.

Further, since the injection molding method is used, it is possible to suppress the generation of residual pores as in the case of using the sintering method or the like, and it is possible to accurately and inexpensively form a molded product having a complicated shape. Moreover, it is possible to mold a large amount.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a schematic view of a glass-based composite material molding machine used in a glass-based composite material molding method according to an embodiment of the present invention, and FIG. 2 is used in a glass-based composite material molding method according to an embodiment of the present invention. It is a principal part enlarged view of a glass base composite material molding machine.

In the figure, 1 is a heating cylinder. The heating cylinder 1 includes a heating cylinder main body 20 and an adapter 21 attached to the tip of the heating cylinder main body 20.
And a nozzle mounting body 22 mounted on the tip of the adapter 21. An injection nozzle 23 is attached to the tip of the nozzle attachment body 22. 26 is a fixed platen, 27 is a fixed mold attached to the fixed platen 26, 28 is a movable platen that slides along a tie bar (not shown), and 29 is the movable platen 28.
It is a movable mold attached to. A cavity 30 is formed between the fixed mold 27 and the movable mold 29, and a sprue 31 is formed to send the glass-based composite material injected from the injection nozzle 23 to the cavity 30.

A screw 33 is installed in the heating cylinder 1.
Is rotatably and movably arranged. A rotary drive device 35 such as an oil motor is arranged at the rear end of the screw 33. The screw 33 includes a conical portion 33a formed at the tip, a ring-shaped portion 33b formed following the conical portion 33a, and a helical groove 34.
It is composed of a screw body portion 33c in which And
The outer diameter of the ring-shaped portion 33b is made slightly smaller than the inner diameter of the heating cylinder 1 so that the screw 33 can be moved within the heating cylinder 1. Further, the ring-shaped portion 33b is coated with a titanium nitride (titanium nitride) -based coating in order to particularly improve wear resistance.

In the glass-based composite material molding machine having the above-described structure, when the measurement is started toward the next injection molding shot, the screw 33 is placed at the measurement position as shown by the solid line in FIG. Therefore, the recess 36 is formed in the inner peripheral surface of the adapter 21 at a portion corresponding to the measuring position of the screw 33.
Is formed. The recess 36 is formed along the inner circumference of the adapter 21, and as shown in FIG. 2, when the screw 33 is placed in the measuring position, the ring-shaped portion 33b faces the recess 36 and the ring-shaped portion 33b is formed. An annular gap (link) 38 that communicates the front (left side in the figure) and the rear (right side in the figure) of is formed.

When the screw 33 is placed at the measuring position, the gap 38 serves as a flow path for the glass-based composite material having an opening between the front and the rear of the ring-shaped portion 33b. In the present embodiment, the concave portion 36 is formed on the entire inner circumferential surface of the adapter 21 in the circumferential direction, but it may be formed only on a part of the circumferential direction. In this case, the shape of the gap 38 is different.

A hopper 40 is provided at the rear end of the heating cylinder 1, and an electromagnetic induction heating device 53 and a thermocouple 54 are provided at the lower end of the hopper 40. Then, the pellet 41 of the glass-based composite material contained in the hopper 40 is maintained at a set temperature equal to or higher than the transition point of the glass material and equal to or lower than the softening point by a control device (not shown). For example, in the case of a glass material containing 25% by weight of B ₂ O ₃ , 60% by weight of PbO, and 15% by weight of ZnO, the set temperature is 380 ° C. or higher and 450 ° C.
It is set below.

In this state, the screw 33 is rotated by the rotation driving device 35, and the pellets 41 accommodated in the hopper 40 are moved forward in the groove 34 by the rotation of the screw 33 while the heating cylinder 1 is being rotated.
It is heated and melted inside, and is supplied to the front storage part 43 through the gap 38. The inner peripheral surface of the recess 36 is surface-treated in order to smooth the flow of the glass-based composite material.

At this time, the injection nozzle 23 is left as it was in the previous injection molding shot, the opening is closed by the sprue 31, and the glass-based composite material is stored in the storage section 4.
Continue to be sent to 3. Then, the glass-based composite material is stored in the storage unit 4.
When 3 is satisfied, the rotation of the screw 33 is stopped. Therefore, a pressure sensor (not shown) as a state detecting means in the heating cylinder 1 is provided in the recess 36, the pressure of the glass base composite material is detected by the pressure sensor, and a detection signal is sent to a control device (not shown). It has become. The recess 36 may be provided with other state detecting means such as a temperature sensor (not shown).

During this period, the glass-based composite material of the previous injection molding shot is cooled in the cavity 30, and when cooling is completed, the mold is opened and a molded product (not shown) is ejected by an ejector device (not shown). Then, the mold is closed and the mold is closed again, and the injection is started. That is, at the time of injection, the screw 33 is advanced to the injection most advanced position by an injection cylinder (not shown) or the like. At this time, since the ring-shaped portion 33b forms a sealing surface so as to face the inner peripheral surface of the adapter 21, the glass-based composite material in front of the ring-shaped portion 33b does not flow backward backward. Therefore, the glass-based composite material of the storage unit 43 is pushed forward by the ring-shaped portion 33b and ejected from the ejection nozzle 23.

In FIG. 1, the broken line shows the most advanced injection position of the screw 33, but normally the screw 33 is
Reaches the injection end position from the injection start position to the injection most advanced position, and the glass-based composite material moves to the cavity 3
Fill within 0. Therefore, the resistance of the glass-based composite material at that time can be detected, and the pressure-holding step or the cooling step can be performed.

In this case, since there is no member that moves with the forward movement of the screw 33 unlike the conventional non-return ring, the backflow amount of the glass-based composite material is small. Therefore,
The amount and speed of the injected glass-based composite material can be kept constant, and the quality of molded products will not vary, and it will be possible to mold precision molded products and thin molded products. . Incidentally, a conventional plunger type injection molding machine, a screw type injection molding machine, an injection molding machine combining them, or the like, which does not include a check ring, can be similarly used.

Then, when the injection is completed, the screw 33 is forcibly retracted by the injection cylinder or the like to the measuring position shown by the solid line in FIG. Due to this retreat, the pressure inside the storage unit 43 is reduced. By the way, the pellet 4
1 is a glass material as a base material and short fibers (length 10 [μ] ~
3 [mm]), whiskers (length 1 to 10 [μ]), particles (diameter 0.1 to several hundreds of micron), and other glass-based composite materials dispersed therein, and formed into capsules. It is molded, or it is molded into a cylindrical shape with chamfered parts on both ends,
It is formed into a columnar shape with rounded portions at both ends.

As the glass material, a borate-based low melting point glass is used. The additive is made of metal, ceramics, glass material or the like. In the case of metal, W,
Short fibers, whiskers, particles or the like made of a simple metal such as Mo, Ni, Fe, Cr, Cu or an alloy thereof are used. In the case of ceramics, Al ₂ O ₃ , Zr
Short fibers, whiskers, particles or the like made of O ₂ , SiO ₂ , SiC, Si ₃ N ₄ or the like are used.

The pellet 41 can be molded by various methods. That is, in the first method, first, the powdery glass material and the additives are mixed by a mixer (not shown) to form a glass-based composite material, which is heated and melted in a crucible (not shown). In this case, since the glass material and the additive are mixed by the mixer, the additive is uniformly dispersed. After that, the molten glass-based composite material is extruded from the outlet of the crucible and cut into a pellet 41 in a semi-molten state. The pellets 41 can be molded by casting after being taken out from the crucible.

In the second method, powdery glass material and additives are mixed to form a glass-based composite material, which is poured into a mold (not shown) having a predetermined shape. And
The glass-based composite material is heated and sintered into pellets 41.
Becomes In the third method, powdery glass material and additives are mixed by a ball mill (not shown) at a set temperature equal to or higher than the transition point of the glass material and equal to or lower than the softening point to form a glass-based composite material, which is sufficiently integrated. , Poured into a mold having a predetermined shape. Then, the glass-based composite material is heated and sintered to form the pellet 41.

In the fourth method, a powdery glass material and additives are mixed by, for example, a ball mill at a set temperature not lower than the transition point of the glass material but not higher than the softening point to form a glass-based composite material, which is near the softening point. The pellet 41 is formed by press molding with a mold having a predetermined shape at a set temperature. In the fifth method, powdery glass material and additives are mixed by, for example, a ball mill at a set temperature equal to or higher than the transition point of the glass material and equal to or lower than the softening point to form a glass-based composite material, and a semi-molten state is obtained by an extruder (not shown). Are extruded and cut into pellets 41.

When the pellet 41 is a porous body having a predetermined porosity, the glass-based composite material is a hopper 4.
Immediately after being supplied into the heating cylinder 1 from 0, the screw 33 is deformed by the rotation of the screw 33, and the fluidity is increased.
As described above, since the additive is uniformly dispersed in the raw material stage, that is, in the state of the pellet 41, the additive is uniformly dispersed in the molded product, and the quality of the molded product can be improved. Moreover, since the melting time of the glass material is shortened, the reaction of the glass material and the additive is suppressed, and the toughness of the molded product can be increased.

Furthermore, since a sharp edge is not formed on the end surface of the pellet 41 when the pellet 41 is molded, abrasion of the screw 33 and both molds 27, 29 can be suppressed, and the glass base material can be suppressed. The durability of the composite material molding machine can be improved. The pellet 41 is screw 33 by any one of the first to fifth methods.
It is shaped to fit in the groove 34 of and has a diameter of 2 to 4 [mm].
And the length is set to 3 to 10 [mm].

When the screw 33 is rotated by the rotation driving device 35, the pellet 41 of the glass-based composite material contained in the hopper 40 is transferred to the screw 33.
Is rotated in the groove 34 to move forward and is heated in the heating cylinder 1 to be melted and becomes hotter as it moves to the tip, passing through the gap 38 and reaching the front storage part 43.
Is supplied to. Then, when the glass-based composite material fills the storage portion 43, the rotation of the screw 33 is stopped.

The pellet 41 is replaced with the hopper 40.
In the interior of the glass material, the glass material is preheated to a set temperature of not less than the transition point of the glass material and not more than the softening point thereof, and then the glass material is supplied into the heating cylinder 1, whereby the initial plasticization of the glass-based composite material is made sound and the heating cylinder 1 or The durability of the screw 33 can be improved. Next, at the time of injection, the screw 33 is advanced to the injection advanced position by an injection cylinder (not shown) or the like. At this time, since the ring-shaped portion 33b forms a sealing surface so as to face the inner peripheral surface of the adapter 21, the glass-based composite material in front of the ring-shaped portion 33b does not flow backward backward. Therefore, the glass-based composite material of the storage unit 43 is the same as the ring-shaped portion 3.
It is pushed forward by 3b and ejected from the ejection nozzle 23.

When a screw head having a non-return ring is used as the screw 33, when the injection molding is finished and the measurement is started toward the next injection molding shot, the state of not completely melted is obtained. The glass matrix composite may remain on the screw head. in this case,
The screw 33 becomes a head lock state and the screw head is broken.

The glass-based composite material molding machine is not limited to this type, and an ordinary injection molding machine can be used. A plunger type injection molding machine can also be used. In this case, the pellets 41 are supplied into the heating cylinder 1, sufficiently heated and melted, and then injected by a plunger (not shown).

The present invention is not limited to the above-mentioned embodiments, but can be variously modified within the scope of the present invention, and they are not excluded from the scope of the present invention.

[0036]

As described in detail above, according to the present invention, in the glass-based composite material molding method, the glass material and the additive to be the base material are mixed to form the glass-based composite material, and the glass-based composite material is formed. The material is heated to a set temperature and formed into pellets. Next, the pellet-shaped glass-based composite material was heated in advance to a softening point or lower above the transition point of the glass material and then fed into a heating cylinder, and further heated and melted in the heating cylinder to be melted. Inject the glass matrix composite.

In this case, since the additive is uniformly dispersed in the raw material stage, that is, in the state of pellets, the additive is uniformly dispersed in the molded product, and the quality of the molded product can be improved. Further, since the melting time of the glass material is shortened, the reaction of the glass material and the additive is suppressed,
The toughness of the molded product can be increased.

[Brief description of drawings]

FIG. 1 is a schematic view of a glass-based composite material molding machine used in a glass-based composite material molding method according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of a glass-based composite material molding machine used in a glass-based composite material molding method according to an embodiment of the present invention.

[Explanation of symbols]

 1 Heating Cylinder 27 Fixed Mold 29 Movable Mold 41 Pellets

Claims (6)

[Claims] 1. A glass material and a base material are mixed to form a glass-based composite material, and (b) the glass-based composite material is heated to a preset temperature to be molded into pellets. ) The pellet-shaped glass-based composite material is heated in advance to a softening point or higher above the transition point of the glass material and then fed into a heating cylinder, and further heated and melted in the heating cylinder, (d)
A method of molding a glass-based composite material, which comprises injecting a melted glass-based composite material. 2. The pelletized glass-based composite material is formed by mixing powdery glass material and additives with a mixer and then melting the mixture, and cutting the melted glass-based composite material in a semi-molten state. The glass-based composite material molding method according to claim 1, wherein 3. The glass according to claim 1, wherein the pellet-shaped glass-based composite material is formed by mixing powdery glass material and additives, injecting the mixture into a mold, and then heating and sintering the mixture. Base composite material molding method. 4. The pellet-shaped glass-based composite material is prepared by mixing powdery glass material and additives at a set temperature not lower than the transition point of the glass material and not higher than the softening point, and pouring the mixture into a mold, followed by heating. The glass-based composite material molding method according to claim 1, which is formed by sintering. 5. The pellet-shaped glass-based composite material is obtained by mixing powdery glass material and additives at a set temperature not lower than the transition point and not higher than the softening point of the glass material, and mold at a set temperature near the softening point. The glass-based composite material molding method according to claim 1, wherein the glass-based composite material molding method is performed by press molding. 6. The pellet-shaped glass-based composite material, powdered glass material and additives are mixed at a set temperature not lower than the transition point and not higher than the softening point of the glass material, and extruded in a semi-molten state by an extruder, The glass-based composite material molding method according to claim 1, which is formed by cutting.