TW201524749A - Manufacturing method of low warpage deformation composite material plate - Google Patents

Abstract

A manufacturing method of low warpage deformation composite material plate is disclosed, which comprises: to mix the reinforcing material containing fibers and the thermosetting resin to form a mixture; to proceed the first stage of heating to the mixture so that the mixture can reach about 50% degree of cure; to proceed the second stage of heating to the mixture so that the mixture can reach about 70% degree of cure; wherein the temperature of the second-stage heating is higher than the temperature of the first-stage heating, and is slightly lower than the curing temperature of the thermosetting resin; to proceed the third-stage heating to the mixture so that the mixture can reach more than 95% degree of cure; wherein the temperature of the third-stage heating is higher than the curing temperature of the thermosetting resin. In this way, a low warpage deformation composite material plate with high planarity (less than 0.1mm per meter) can be manufactured.

Description

Low warpage deformation composite material plate manufacturing method

The present invention relates to a method of manufacturing a composite sheet, and more particularly to a method of manufacturing a low warpage deformed composite sheet.

In recent years, due to the advancement of science and technology, the requirements for material quality have become more and more strict. Traditional materials have not met the requirements in some characteristics. Therefore, composite materials with light weight, high strength and good elasticity have emerged. The composite materials are produced by A combination of two or more materials consisting of a base material and a reinforcing material. Generally, the base material is a material with a continuous material composition, and the reinforcing material is a discontinuous material. Usually, the reinforcing material has excellent mechanical properties. The strength makes the composite material different from any of its constituent materials, but presents new material properties.

The polymer composite material in the composite material is based on polymer plastic, and the fiber is a reinforcing material. The fiber can be uniformly dispersed in the polymer plastic in different forms to increase the strength of the material, and the polymer plastic must undergo a curing process. In order to fully cure the polymer plastic, and to make the mechanical properties of the gel more favorable, to achieve a stable state to increase product reliability, but due to different thermal expansion coefficients of the materials in the composite material, or uneven degree of ripening, etc., will cause compounding The material produces warping deformation.

In the machinery industry, machining needs to be often on the machine. Measure the size of the workpiece to ensure the inspection after the machine is finished. The most commonly used measuring tools include vernier calipers and centimeter cards. For large workpieces, large measuring tools of corresponding length are required. Traditional measuring tools are made of steel, and vernier calipers are used as an example. When the length of the vernier caliper exceeds one meter, the gauge has a considerable weight, so it is quite difficult to operate, and the fiber composite has a specific gravity of only 1/5 of the steel, so the manufactured vernier caliper can reduce the weight beyond the steel vernier caliper. 50% weight.

However, except for the difference in thermal expansion coefficient of each material in the composite material In addition to the warpage deformation caused by the flat plate forming and heating process, the mold will also become longer due to thermal expansion, and the friction between the mold and the composite material plate will also be caused during the process of cooling the mold back to the original length after molding. The side of the composite plate that is in contact with the mold is subjected to pressure, which causes the composite material to warp and deform after being formed. The longer the composite material plate is, the more severe the warpage deformation after molding is. Generally, the composite material plate is manufactured, and the actual measurement degree of warpage is actually measured. The meter reaches about 1mm, and must be repeated after the processing such as grinding and inspection, but the fiber will be deformed during the grinding process, and the damage caused by a large number of grinding fibers is more serious, resulting in performance degradation, and the compensation performance is compromised. The high fiber volume content and the use of expensive high modulus fibers increase the difficulty of adding and grinding, so that the cost cannot be reduced.

Therefore, the industry is in great need of developing a low warpage deformation composite. The manufacturing method of the material plate can be applied to the production of large measuring tools to prepare A large-scale measuring tool with light weight, high strength and high flatness.

In view of the above disadvantages of the prior art, the main object of the present invention is to provide a method for manufacturing a low warpage deformation composite material sheet, integrating a fiber-containing reinforcing material, a thermosetting resin, a three-stage heating program, etc., to prepare an applicable method. For the production of large-scale measuring tools, we can produce large-scale measuring tools with light weight, high strength and high flatness.

In order to achieve the above object, according to one aspect of the present invention, a method for manufacturing a low warpage deformation composite material sheet comprising: mixing a fiber-containing reinforcing material with a thermosetting resin to form a mixture; Stage hot pressing to bring the mixture to about 5 maturity; the mixture is subjected to a second stage of heating to bring the mixture to a ripening degree of about 7, wherein the second stage heating temperature is higher than the first stage heating temperature and Lower than the curing temperature of the thermosetting resin; the mixture is subjected to a third-stage heating to bring the mixture to a degree of ripening of 9.5 or more, wherein the third-stage heating temperature is higher than the curing temperature of the thermosetting resin.

In the above method for producing a low warpage deformation composite material sheet, the thermosetting resin may be selected from one of a phenol resin, an epoxy resin, a polyamidene, a cyanate ester, or a mixture thereof.

In the method for manufacturing a low warpage deformed composite material sheet, the mixture is a prepreg obtained by mixing the reinforcing material containing fibers with the thermosetting resin; the prepreg is a mixture of fibers and resin, generally uniformly coating the resin. The coating is attached to the fiber because the resin is viscous, so the prepreg is semi-cured before heating to cure the resin.

Composite material (prepreg type) during molding heating process, mold It will also become longer due to thermal expansion, and during the process of mold cooling and retracting to the original length after molding, a frictional force will be generated between the mold and the composite due to the difference in expansion coefficient between the mold and the composite material. The side that causes the composite material to contact the mold is subjected to pressure, resulting in warping deformation of the composite material after molding. Therefore, in the method for manufacturing the low warpage deformation composite material sheet of the present invention, the mixture and the mold have at least one low friction release layer ( Release layer) to reduce the friction.

The method for manufacturing a composite material sheet of the present invention can be molded into The preform, the hot press molding, the autoclave molding, the resin transfer molding method, the hand molding method, and the like, the prepreg is formed into a desired shape.

In order to achieve the above object, the other party proposed in accordance with the present invention Provided is a method for manufacturing a low warpage deformation composite material comprising: a fiber-containing reinforcing material (for example, T700S unidirectional carbon fiber, but not limited thereto) and a thermosetting resin (for example, a 250°F epoxy resin, but Without limitation, mixing to form a prepreg; placing the prepreg in a mold, and subjecting the prepreg to a first stage of hot pressing to form the composite sheet into a composite sheet. And achieving a degree of maturity of about 5, wherein the prepreg and the mold have at least one low friction release layer; the second stage heating of the composite sheet, the composite sheet reaches about 7 maturity, wherein The second stage heating temperature is higher than the The first stage heating temperature is slightly lower than the curing temperature of the thermosetting resin; the third stage heating is performed on the composite board to achieve a degree of ripening of the composite sheet of about 9.5 or more, wherein the third step heating temperature is higher than The curing temperature of the thermosetting resin; wherein the thermosetting resin has a first curing temperature of about 80 ° C and a curing temperature of about 120-130 ° C.

According to another aspect proposed by the present invention, the first stage is added The heat system is heated at a temperature of 80-85 ° C, and the heating temperature range is determined according to the initial curing temperature of the thermosetting resin; the second stage heating is performed at a temperature ranging from 110 to 120 ° C; the second stage heating system Heating is carried out at a temperature of 130 ° C or higher.

In order to achieve the above object, the other party proposed in accordance with the present invention Provided is a method for manufacturing a low warpage deformation composite material comprising: a fiber-containing reinforcing material (for example, T700S unidirectional carbon fiber, but not limited thereto) and a thermosetting resin (for example, a 350°F epoxy resin, but Without limitation, mixing to form a prepreg; placing the prepreg in a mold, and performing the first stage hot pressing on the prepreg, the first stage of the hot pressing system having a temperature range of 120 The temperature of °C is hot pressed to shape the prepreg into a composite sheet and achieve a maturity of about 5, wherein the prepreg and the mold have at least one low friction release layer; Two-stage heating, the second-stage heating is performed in a temperature range of 180-190 ° C to achieve a maturity of the composite sheet, wherein the second-stage heating temperature is higher than the first-stage heating temperature and slightly lower The curing temperature of the thermosetting resin; the third of the composite sheet Stage heating, the third stage heating is performed at a temperature of at least 200 ° C or higher to achieve a degree of ripening of the composite sheet of about 9.5 or more, wherein the third-stage heating temperature is higher than a curing temperature of the thermosetting resin; wherein The thermosetting resin has a pre-aging temperature of about 120 ° C and a curing temperature of about 190-200 ° C.

In the above method for manufacturing a low warpage deformation composite material plate according to each aspect of the present invention, a low warpage deformation composite material sheet having a warpage degree of less than 0.1 mm per square meter of deformation can be prepared.

The above summary and the following detailed description and drawings are intended to further illustrate the manner, means and effects of the present invention in achieving its intended purpose. Other purposes and advantages of this creation will be explained in the following description and drawings.

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21, 51‧‧‧ composite board

41‧‧‧ Pressure line

I‧‧‧First stage heating procedure

II‧‧‧Second stage heating procedure

52‧‧‧shims

53‧‧‧Mold

The first figure is a flow chart of a method for manufacturing a low warpage deformation composite material according to the present invention; the second figure is a schematic view of a composite material board according to the present invention; and the third A figure is a prepreg material of the composite material board of the present invention. Schematic diagram of DSC thermal analysis before heating; the third B is a schematic diagram of DSC thermal analysis of a prepreg of a composite material sheet after heating; the fourth figure is the first and second of a composite material board of the present invention The schematic diagram of the stage heating process; the fifth figure is a schematic diagram of the third stage heating molding of the composite material sheet of the present invention.

The embodiments of the present invention are described by way of specific examples, and those skilled in the art can readily understand the advantages and effects of the present invention from the disclosure of the present disclosure.

Please refer to the first figure for a flow chart of a method for manufacturing a low warpage deformation composite material according to the present invention. As shown, the present invention provides a method for manufacturing a low warpage deformation composite material, comprising: mold preparation (S11), which can be performed by a hot press, autoclave hot press forming, or room temperature press molding, or resin transfer molding. The composite material is shaped by the method, the hand forming method, etc., therefore, different molds are used for different methods; the low friction release layer is confirmed (S12), and the invention avoids the original length of the composite material after the molding is cooled by the mold cooling. During the process, the friction between the mold and the composite material causes the side of the composite material in contact with the mold to be subjected to pressure, resulting in bending and deformation of the composite material after molding, so the silicon layer can be coated on the inner edge of the mold (but not limited thereto). Or placing a Teflon film between the mold and the composite material (but not limited to) to reduce the friction between the mold and the composite material; material preparation (S13), for example, carbon fiber and epoxy resin Forming a prepreg; performing the first stage heating (S14), the composite prepreg can be hot pressed by a hot press or an autoclave, or the composite can be formed by a resin transfer molding method or a hand forming method. The material prepreg is subjected to a first stage of heating (S14), and the composite material is subjected to a first stage molding and a degree of ripening of at least 50%, wherein the degree of cure is a conversion rate. It can be represented by spectral analysis, chemical analysis, dynamic mechanical analysis (DMA, TMA) and differential scanning calorimeter (DSC) thermal analysis, or using commercially available curing degree measuring machines. The degree of ripening of the composite material can be measured. Among them, the differential scanning calorimeter (DSC) thermal analysis can calculate the degree of ripening by the following formula: △ H _O is the total amount of heat released by the unheated resin just after full ripening ( ), △ H _R is the residual reaction heat after aging ( Then, the second stage heating (S15) is performed, after the first stage hot pressing process is completed, the composite material has completed the shaping of the basic shape, and the excess glue is discharged, so the second stage hot pressing program can be used. The mold or machine used in one stage continues to be heated, or the second stage heating process can be performed only by using a general mold forming machine. The second stage heating temperature is higher than the first stage heating temperature and slightly lower than the a curing temperature of the thermosetting resin, wherein the composite material is subjected to a second-stage hot pressing (S15) to achieve a ripening degree of the composite material of at least 70% (the degree of ripening is calculated as described in the above formula); and then the third-stage heating is performed ( S16), the third-stage heating program can continue to use the mold used in the first stage, the machine can continue to be heated, or the third stage heating process can be performed only by using a general mold forming machine. Before heating, the third stage The heating temperature is higher than the glass transition temperature of the thermosetting resin, wherein the composite material is subjected to a third-stage heating (16) to make the composite material have a degree of ripening of more than 95% (curing degree meter) As mentioned above).

Embodiment 1

Please refer to the second figure, which is a schematic view of a composite material board of the present invention. As shown in the figure, in this embodiment, a vernier caliper body having a length of 150 cm, a width of 3 cm, and a thickness of 1.2 cm is prepared, which is required to be a low warpage deformation composite board having a flatness of 0.1 mm or less per meter; this embodiment adopts a T700S single The prepreg made of carbon fiber and 250°F epoxy resin has a glass transition temperature (Tg) of about 110-120 ° C, a curing temperature of about 120-130 ° C, and a single layer forming thickness of about 0.125 mm. Please refer to FIG. 3A , which is a schematic diagram of DSC thermal analysis of a prepreg of a composite material sheet before heating according to the present invention. Referring to FIG. 3B , the prepreg of the composite material sheet is heated according to the present invention. Schematic diagram of post-DSC thermal analysis, as shown in Figure A, the T700S unidirectional carbon fiber plus 250 °F grade epoxy resin prepreg is not heated, it can be known by DSC thermal analysis (third A) , its total heat (△ H _O ) is 111.0 . As shown in Figure B, the prepreg made of T700S unidirectional carbon fiber and 250°F epoxy resin is heated for about 8 hours, and is known by DSC thermal analysis (third B). The residual heat of reaction (Δ H _R ) is 38.64 , so the degree of ripening is calculated by the above formula as (α is the degree of ripening), in other words, after the prepreg is heated for 8 hours, the degree of ripening has reached 65.19% of the degree of ripening.

Please refer to the fourth figure, which is a composite board of the present invention. Schematic diagram of the first and second stage heating procedures. The specific process steps of this embodiment are as follows: Step (1) Cut 96 layers of prepreg made of T700S single-direction carbon fiber and 250°F epoxy resin with a length of 150 cm and a width of 3 cm, and overlap and lay 2 layers of iron. In the mold lower mold of the fluorolong release film (low friction release layer), two layers of Teflon release film (low friction release layer) are laid on the laminated material of the dipping material, and then the mold is molded. The lower mold is closed, the hot press is started to apply pressure to pre-press the prepreg; and the step (2) is to raise the temperature of the mold to 80-85 ° C (in this embodiment, the resin having a preliminary ripening reaction is about 85 ° C or The hardener system, so the first stage heating temperature is 80-85 ° C, but the invention is not limited thereto, such as the use of a lower temperature or even room temperature can occur the resin / hardener system of the initial ripening reaction, the first stage heating temperature The material property is changed), after the prepreg is heated for about 30 minutes, a pressure is applied to the prepreg by a hot press to maintain the mold clamping, at the same temperature and pressure (eg, one atmosphere, but not limited thereto). Maintain 8 hours (as shown in the fourth figure), this is the first stage of hot press forming, due to the longer time, cooked The higher the degree, the molding time can be lengthened at this stage, which is very helpful for reducing the warpage of the finished product; the step (3) raises the mold temperature to 120 ° C (maintaining one atmosphere), and keeps the temperature to room temperature after 2 hours. Stripping out, this is the second stage (such as the fourth figure). At this stage, the curing temperature of the composite sheet is about 120-130 ° C, and the measured flatness is about 0.1-0.2 mm. The warpage source includes the initial flatness of the mold. The combined effects of error, heat shrinkage buckling, friction and the difference in temperature rise and fall of different positions of the mold will be further leveled by the third stage heating; see the fifth stage, which is the third stage of the composite board of the present invention. Schematic diagram of heating and molding, as shown in the figure, step (4) will be compounded The material plate is returned to the mold (53), and the height difference of the mold surface can be adjusted by the gasket according to the warpage condition of the composite material board (51) (but not limited thereto, the embodiment can not slightly adjust the height difference of the mold surface), After the mold is closed, the temperature is slowly raised to 130 ° C, the temperature is lowered to room temperature after 2 hours, and the flat plate after the flattening is taken out by demoulding. The finished composite sheet of the present embodiment is detected by a 3D measuring bed, and the flatness can reach 0.1 mm/ Within m, if the flatness cannot reach 0.1 mm/m, the position of the spacer (52) is readjusted, and the step (4) is repeated to make the flatness of the composite material plate (51) within 0.1 mm/m.

Embodiment 2

The specific process steps of this embodiment are as follows: Step (1) cutting a prepreg 96 made of 150 cm long, 3 cm wide T700S single direction carbon fiber and 350 °F grade epoxy resin (curing temperature of about 190-200 ° C). Layer, overlapped in a mold lower mold with 2 layers of Teflon release film (low friction release layer), and 2 layers of Teflon release film on the laminated material of the dipping material (low friction away) Forming), then clamping the mold upper mold and the lower mold, starting the hot press to apply pressure to pre-press the prepreg; step (2) raising the mold temperature to 120 ° C (about 120 ° C in this embodiment) That is, the resin or hardener system in which the preliminary ripening reaction takes place, so the first stage heating temperature is 120 ° C, but the present invention is not limited thereto, such as a resin/hardener system which can be subjected to preliminary ripening reaction using a lower temperature or even a room temperature. The first stage heating temperature changes according to the material property), after the prepreg is heated for about 30 minutes, a pressure is applied to the prepreg by a hot press to maintain the mold clamping at the same temperature and pressure (eg, one atmosphere, but not This is limited to 8 hours, this is the first stage of hot press forming, due to time The longer the age, the higher the degree of ripening, so the molding time at this stage can be lengthened as needed. It is very helpful to reduce the warpage of the finished product; in step (3), the mold temperature is raised to 180 ° C (maintaining one atmosphere), and after 2 hours, the temperature is lowered to room temperature, and the mold is taken out. This is the second stage. The curing temperature of the flat plate is about 190-200 ° C, and the measured flatness is about 0.1-0.2 mm. The warping source includes the initial flatness error of the mold, the heat shrinkage buckling, the friction force and the combined effect of the difference in the temperature rise and fall rates of different positions of the mold. Further, the third stage heating is used for further leveling; in step (4), the composite material sheet is returned to the mold (53), and the height of the mold surface is adjusted by the gasket according to the warpage of the composite material board (51) (but not To be limited to this, the embodiment can not slightly adjust the height difference of the mold surface), slowly heats up to 200 ° C after the mold is closed, returns to room temperature after holding the temperature for 2 hours, and removes the flattened composite board after demolding. The finished product board is tested by 3D measuring bed, the flatness can reach 0.1mm/m. If the flatness cannot reach 0.1mm/m, re-adjust the position of the gasket (52) and repeat step (4). The flatness of the composite sheet (51) is within 0.1 mm/m.

The above-described embodiments are merely illustrative of the features and functions of the present invention and are not intended to limit the scope of the technical content of the present invention. Any person skilled in the art can modify and change the above embodiments without departing from the spirit and scope of the creation. Therefore, the scope of protection of this creation should be as listed in the scope of the patent application described later.

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Claims (10)

A method for manufacturing a low warpage deformation composite material comprising: mixing a fiber-containing reinforcing material with a thermosetting resin to form a mixture; and subjecting the mixture to a first stage hot pressing to bring the mixture to about 5 maturity; The mixture is subjected to a second stage of heating to bring the mixture to a ripening degree of about 7, wherein the second stage heating temperature is higher than the first stage heating temperature and slightly lower than the curing temperature of the thermosetting resin; Heating, the mixture is brought to a degree of ripening of about 9.5 or more, wherein the third-order heating temperature is higher than the curing temperature of the thermosetting resin. The method for producing a low warpage deformation composite according to the above aspect of the invention, wherein the thermosetting resin is one selected from the group consisting of a phenol resin, an epoxy resin, a polyimine, and a cyanate ester, or a mixture thereof. The method for producing a low warpage deformation composite material according to claim 1, wherein the mixture is a prepreg obtained by mixing the fiber-containing reinforcing material with the thermosetting resin. The method of manufacturing a low warpage deformation composite according to claim 3, wherein the mixture and the mold have at least one low friction release layer. A method for manufacturing a low warpage deformation composite board, comprising: The fiber-containing reinforcing material is mixed with the thermosetting resin to form a prepreg; the prepreg is placed in a mold, and the prepreg is subjected to a first stage hot pressing to form the prepreg into a The composite sheet reaches a ripening degree of about 5, wherein the prepreg and the mold have at least one low friction release layer; the second stage heating of the composite sheet causes the composite sheet to reach about 7 maturity Degree, wherein the second stage heating temperature is higher than the first stage heating temperature and slightly lower than the curing temperature of the thermosetting resin; the third stage heating is performed on the composite material sheet, so that the composite material board reaches about 9.5 % or more The degree of ripening, wherein the third-stage heating temperature is higher than the curing temperature of the thermosetting resin; wherein the thermosetting resin has a first curing temperature of about 80 ° C and a curing temperature of about 120-130 ° C. The method for producing a low warpage deformation composite according to claim 5, wherein the first stage heating is performed at a temperature ranging from 80 to 85 °C. The method for producing a low warpage deformation composite according to claim 5, wherein the second stage heating is performed at a temperature ranging from 110 to 120 °C. The method for producing a low warpage deformation composite material according to claim 5, wherein the third stage heating system is heated at a temperature of 130 ° C or higher. A method for manufacturing a low warpage deformation composite material comprising: mixing a reinforcing material containing fibers with a thermosetting resin to form a prepreg; placing the prepreg in a mold, and performing the first prepreg One stage of hot pressing, the first stage hot pressing is performed by hot pressing at a temperature ranging from 120 ° C to form the composite sheet into a composite sheet and achieve a maturity of about 5, wherein the prepreg and the mold At least one low friction release layer; the second stage heating of the composite sheet, the second stage heating is heated at a temperature of about 180 ° C to achieve a maturity of about 7 and the second stage The heating temperature is higher than the first-stage heating temperature and slightly lower than the curing temperature of the thermosetting resin; the composite sheet is subjected to a third-stage heating, and the third-stage heating is heated at a temperature of about 200 ° C to make the composite sheet. A curing degree of about 9.5 % or more is achieved, wherein the third-stage heating temperature is higher than a curing temperature of the thermosetting resin; wherein the thermosetting resin has a first curing temperature of about 120 ° C and a curing temperature of about 19 0-200 ° C. The method for manufacturing a low warpage deformation composite material sheet according to claim 9, wherein the low warpage deformation composite material sheet manufacturing method is prepared A low warpage deformation composite sheet with a high flatness within 0.1 mm of the metric deformation.