CN111590048A - Forming die with heat preservation structure - Google Patents

Abstract

The invention relates to the technical field of mold forming, and particularly discloses a forming mold with a heat insulation structure, which comprises a movable mold and a fixed mold, wherein the movable mold and the fixed mold are matched with each other to form a cavity; the outer side surface of the movable mold and/or the outer side surface of the fixed mold are/is coated with a heat insulation layer; the heat insulation layer comprises an aluminum foil layer, a heat insulation material layer and a protective layer which are arranged in sequence from inside to outside; wherein, the thickness ratio between aluminium foil layer, insulation material layer and the inoxidizing coating is 1: 5-10: 1. this forming die can effectively promote the heat preservation effect of mould.

Description

Forming die with heat preservation structure

[ technical field ] A method for producing a semiconductor device

The invention relates to the technical field of mold forming, in particular to a forming mold with a heat insulation structure.

[ background of the invention ]

In injection molding, the temperature of the molten material (e.g., magnesium alloy) injected into the mold is generally 560 ℃ to 620 ℃ and the temperature of the mold is generally 220 ℃ to 290 ℃. However, the mold temperature is rapidly reduced due to mold opening and spraying of the release agent (mold release agent), and heat lost to the air and taken away by the spraying of the release agent (mold release agent) during mold opening. The molding process, once the mold temperature is lowered, has the following effects:

1. from the viewpoint of moldability and molding efficiency, when the mold temperature is low, the fluidity of the molten material in the molding mold is poor and the filling is insufficient; in addition, the mold clamping temperature rise time is prolonged, and the molding efficiency is low.

2. In view of preventing deformation of the molded article, if the cooling rates of the respective portions of the molded article are different, deformation such as warpage or distortion is caused by thermal shrinkage. This can be improved if the temperature of the mold parts is uniform, the temperature being uniformly reduced. For the formed part with completely symmetrical structure, the mold temperature should be kept as consistent as possible, so that the cooling of all parts of the formed part is balanced, and the warping condition of the product is improved.

3. From the effect of mold temperature on the appearance of the product, the reduction of mold temperature can generate cold shut lines (cold streaks) which make the surface of the product uneven, thereby affecting the aesthetic appearance of the product.

4. From the viewpoint of the influence on the thermal stress of the article, since the formation of the molding thermal stress is basically caused by the different thermal shrinkage rates upon cooling, when the article is molded, its cooling is such that the surface gradually extends toward the inside, the surface is first shrinkage-hardened and then gradually moves toward the inside, during which internal stress is generated due to the difference in the rate of shrinkage. Depending on the surface cooling state, the mold rapidly cools down the molten material, which results in a higher residual thermal stress in the product.

5. From the influence on the service life of the mold, the temperature of the mold is high or low during the production process, which not only directly influences the quality of the product, but also influences the service life of the mold. Therefore, the mold is always kept in a certain temperature range in the production process, so that the increase of the shrinkage of the mold due to chilling or the increase of expansion due to heating, the increase of the surface roughness of the mold surface and the generation of cracks can be effectively avoided.

It follows that the mold temperature is one of the important factors in relation to the good appearance quality, mechanical properties, shrinkage and cycle time of the shaped article. However, the heat insulation effect of the existing die-casting mold is not good, and therefore, it is necessary to design a mold having a heat insulation structure to solve the above problems.

[ summary of the invention ]

The invention aims to provide a forming die with a heat insulation structure, which can effectively improve the heat insulation effect of the die.

In order to achieve the purpose, the invention adopts the following technical scheme:

a forming die with a heat insulation structure comprises a movable die and a fixed die which are matched with each other to form a cavity; the outer side surface of the movable mold and/or the outer side surface of the fixed mold are/is coated with a heat insulation layer; the heat insulation layer comprises an aluminum foil layer, a heat insulation material layer and a protective layer which are sequentially arranged from inside to outside; the thickness ratio among the aluminum foil layer, the heat-insulating material layer and the protective layer is 1: 5-10: 1.

further, the heat-insulating material layer comprises a fiber woven fabric layer and a kraft paper layer; the fiber woven fabric layer is attached to the aluminum foil layer; and heat insulation layers are arranged between the fiber woven fabric layer and the kraft layer and between the kraft layer and the protective layer.

Furthermore, the thickness ratio of the fiber woven fabric layer to the kraft paper layer to the thermal insulation layer is 3: 2: 1.

further, the heat insulation layer is a polyethylene film.

Further, the protective layer is an aluminum foil protective layer.

Furthermore, the outer side surface of the aluminum foil protective layer is also provided with a metal coating.

Further, the thickness of the metal coating film is 1 to 2 μm.

Further, the molding die further includes:

the movable mold heating plate is connected with the movable mold, and the outer side surface of the movable mold heating plate is coated with the heat insulation layer; and/or

The cover half hot plate, its with the cover half is connected, just the lateral surface cladding of cover half hot plate has thermal-insulated heat preservation.

The invention has the beneficial effects that: adopt a thermal-insulated heat preservation, this thermal-insulated heat preservation includes aluminium foil layer, insulation material layer and the inoxidizing coating that from interior to exterior set gradually, and wherein, the thickness proportion between aluminium foil layer, insulation material layer and the inoxidizing coating is 1: 5-10: 1. the heat-insulating layer is coated on the outer side surface of the movable mold and/or the outer side surface of the fixed mold, so that the heat-insulating effect of the mold can be effectively improved, the mold is always kept within a certain temperature range in the molding process, the material is guaranteed to be heated in the mold cavity and continuously maintained in a state close to melting, sufficient fluidity is obtained, the mold cavity is smoothly filled, and the injection period is short. In addition, the product formed by the mold has high material compactness and good appearance quality.

[ description of the drawings ]

FIG. 1 is a schematic structural diagram of one embodiment of a forming mold with a heat preservation structure provided by the invention;

FIG. 2 is a schematic structural diagram of another embodiment of a forming mold with a heat preservation structure provided by the invention;

fig. 3 is a schematic view of the structure of the thermal insulation layer of fig. 1.

[ detailed description ] embodiments

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

As shown in fig. 1 to 3, a forming mold with a heat preservation structure comprises a movable mold 10 and a fixed mold 20 which are matched with each other to form a cavity; the outer side surface of the movable mold 10 and/or the outer side surface of the fixed mold 20 are/is coated with a heat insulation layer 30; the heat insulation layer 30 comprises an aluminum foil layer 31, a heat insulation material layer 32 and a protective layer 33 which are arranged in sequence from inside to outside; wherein, the thickness ratio among aluminium foil layer 31, thermal insulation material layer 32 and inoxidizing coating 33 is 1: 5-10: 1.

specifically, in the molding die, the aluminum foil layer 31 has a thickness of 7 μm. The thermal insulation material layer 32 includes a fiber woven layer 321 and a kraft paper layer 322. The fiber woven fabric layer 321 is attached to the aluminum foil layer 31; heat insulating layers 323 are arranged between the fiber woven layer 321 and the kraft layer 322 and between the kraft layer 322 and the protective layer 33. The thickness ratio of the fiber woven fabric layer 321, the kraft paper layer 322 and the heat insulation layer 323 is 3: 2: 1.

as a preferable embodiment of the present invention, the heat insulating layer 323 is a polyethylene film; the protective layer 33 is an aluminum foil protective layer, which can simultaneously achieve the purposes of heat insulation and protection.

The heat insulation layer 30 adopted by the invention is formed by laminating an aluminum foil layer 31, a fiber woven fabric layer 321, a kraft paper layer 322, a heat insulation layer 323 and a protective layer 33 by hot melt adhesive. Therefore, the aluminum foil layer 31 attached to the mold in the heat-insulating layer 30 has the advantages of smooth and flat surface, high light reflectivity, large longitudinal and transverse tensile strength, air impermeability, water impermeability, good sealing performance, strong weather resistance and the like.

Furthermore, the outer side surface of the aluminum foil protective layer is also provided with a metal coating film 34. The thickness of the metal coating film 34 is 1 to 2 μm.

The forming die further comprises a movable die heating plate 40 connected with the movable die 10 and/or a fixed die heating plate 50 connected with the fixed die 20. In order to further reduce heat loss, the heat insulating layer 30 may be coated on the outer surface of the movable mold heating plate 40 and/or the outer surface of the fixed mold heating plate 50.

According to the forming die, the outer side surface of the die is coated with the heat insulation layer 30, so that the die is always kept in a certain temperature range in the forming process, the material is continuously heated in the die cavity of the die and is kept in a state close to melting, sufficient fluidity is obtained, the die cavity is smoothly filled, and the injection period is shortened. In addition, the product formed by the mold has high material compactness and good appearance quality.

The technical principles of the present invention have been described above in connection with specific embodiments, which are intended to explain the principles of the present invention and should not be construed as limiting the scope of the present invention in any way. Based on the explanations herein, those skilled in the art will be able to conceive of other embodiments of the present invention without inventive effort, which would fall within the scope of the present invention.

Claims (8)

1. A forming die with a heat insulation structure comprises a movable die and a fixed die which are matched with each other to form a cavity; the heat insulation device is characterized in that the outer side surface of the movable die and/or the outer side surface of the fixed die are/is coated with a heat insulation layer; the heat insulation layer comprises an aluminum foil layer, a heat insulation material layer and a protective layer which are sequentially arranged from inside to outside; the thickness ratio among the aluminum foil layer, the heat-insulating material layer and the protective layer is 1: 5-10: 1.

2. the forming die of claim 1, wherein the thermal insulation material layer comprises a fiber woven fabric layer and a kraft paper layer; the fiber woven fabric layer is attached to the aluminum foil layer; and heat insulation layers are arranged between the fiber woven fabric layer and the kraft layer and between the kraft layer and the protective layer.

3. The forming die of claim 2, wherein the thickness ratio among the fiber woven fabric layer, the kraft paper layer and the thermal insulation layer is 3: 2: 1.

4. the forming die of claim 2, wherein the thermal insulation layer is a polyethylene film.

5. The forming die of claim 1, wherein the protective layer is an aluminum foil protective layer.

6. The forming die of claim 5, wherein the outer side surface of the aluminum foil protective layer is further provided with a metal coating.

7. The molding die according to claim 6, wherein the thickness of the metal coating film is 1 μm to 2 μm.

8. The molding die according to any one of claims 1 to 7, characterized in that the molding die further comprises:

the movable mold heating plate is connected with the movable mold, and the outer side surface of the movable mold heating plate is coated with the heat insulation layer; and/or

The cover half hot plate, its with the cover half is connected, just the lateral surface cladding of cover half hot plate has thermal-insulated heat preservation.

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