JP2014108612A - Analysis method in molding carbon fiber reinforced plastic, and analyzer - Google Patents

Abstract

An object of the present invention is to provide an analysis method and an analysis apparatus for molding a carbon fiber reinforced plastic capable of predicting the shape at the time of molding with high accuracy.
SOLUTION: A target shape when a CFRP material 30 made of carbon fiber reinforced plastic of thermosetting resin is molded, and a degree of curing when the prepreg temperature 50 of the CFRP material 30 is increased and curing is progressing. Based on the information about the CFRP material 30 including the physical property value of the CFRP material 30 near 50%, and the analysis conditions including the force applied to the CFRP material 30 and the movement of the CFRP material 30 when the CFRP material 30 is molded, Analysis at the time of forming the CFRP material 30 is performed.
[Selection] Figure 7

Description

  The present invention relates to an analysis method and an analysis apparatus for molding a carbon fiber reinforced plastic.

  In recent years, some structural members of aircraft, automobiles, and the like use so-called carbon fiber reinforced plastics (CFRP), which are light weight and high strength composite members. This CFRP is a composite member using a synthetic resin as a base material and carbon fiber as a reinforcing material, and may be used as a structural member in various fields such as golf clubs that require lightness and strength. It is increasing.

  In addition, CFRP is often formed by using a sheet-like material called a prepreg, which is obtained by impregnating a carbon fiber with a thermosetting resin in advance and making it semi-cured. There are various methods for manufacturing such a member using CFRP, and one of them is a method of forming a material using CFRP by press molding. For example, in the method for producing a fiber-reinforced composite material described in Patent Document 1, a prepreg is formed by interposing a non-impregnated nonwoven fabric between sheet-like CFRP layers in which carbon fibers are impregnated with an unsaturated polyester resin. A desired product is obtained by forming a laminated body and applying a predetermined pressure to the prepreg laminated body with a molding die to perform pressure molding.

JP 2008-246981 A

  In press molding, in order to obtain the desired molded product shape by applying pressure to the material and deforming the material, the target shape at the time of molding and the actual shape are adjusted according to the ease of deformation of the material Differences occur. On the other hand, the viscosity of a prepreg laminate for obtaining a CFRP molded product changes with temperature, and the ease of deformation is improved by lowering the viscosity at the beginning of the molding process when the temperature rises. Since the temperature distribution in the sheet surface of the laminate is not uniform, the ease of deformation of the prepreg laminate is also not uniform in the sheet surface. For this reason, in the CFRP press-molded product, the difference between the target shape at the time of molding and the actual shape differs depending on the part. Therefore, it is very difficult to accurately analyze and predict the shape obtained by molding before molding CFRP and to increase the design accuracy of the mold.

  The present invention has been made in view of the above, and provides an analysis method and an analysis apparatus for molding a carbon fiber reinforced plastic capable of analyzing and predicting a shape at the time of molding with high accuracy. Objective.

  In order to solve the above-described problems and achieve the object, the analysis method at the time of molding the carbon fiber reinforced plastic according to the present invention is a target when molding a material made of carbon fiber reinforced plastic of thermosetting resin. Information on the material including the shape, the physical property value of the material in the vicinity of 50% of the degree of curing when the temperature of the material is increased and the curing is progressing, and the force applied to the material at the time of molding the material And an analysis condition including the movement of the material, an analysis at the time of forming the material is performed.

  Further, in the analysis method at the time of molding the carbon fiber reinforced plastic, the target shape at the time of molding the material, the information on the material, and the analysis conditions include an analysis process at the time of molding the material. It is preferable that an analysis is performed by a program and the analysis at the time of forming the material is performed by the analysis device.

  In order to solve the above-described problems and achieve the object, an analysis device for molding a carbon fiber reinforced plastic according to the present invention is a target shape when molding a material made of carbon fiber reinforced plastic, Information, input means capable of inputting analysis conditions including the force applied to the material at the time of molding the material and the movement of the material, and the degree of curing when the temperature of the material is rising and curing is progressing The material including a physical property value acquisition unit that acquires a physical property value of the material in the vicinity of 50%, a target shape at the time of molding, and the physical property value of the material in the vicinity of 50% of the degree of curing acquired in the physical property value acquisition unit And a processing unit that performs analysis at the time of forming the material based on the information and the analysis conditions.

  The carbon fiber-reinforced plastic analyzing apparatus may further include a curing degree deriving unit that derives a physical property value of the material having a curing degree of about 50% based on the physical property value of the material having a curing degree of 100%, The physical property value acquiring unit may acquire the physical property value of the material having a curing degree of about 50% derived from the physical property value of the material having the curing degree of 100% input by the input unit by the curing degree deriving unit. preferable.

  Moreover, in the analysis apparatus for molding the carbon fiber reinforced plastic, the physical property value acquisition unit prompts the input of the physical property value of the material having a curing degree of about 50% when the information on the material is input by the input unit. Is preferred.

  The analysis method and analysis apparatus for molding carbon fiber reinforced plastic according to the present invention can analyze and predict the shape at the time of molding with high accuracy and contribute to improving the design accuracy of the mold. Play.

FIG. 1 is an explanatory view showing a state in which a CFRP material to be molded is put into a mold. FIG. 2 is an explanatory view showing a state in which heat is transferred to the CFRP material. FIG. 3 is an explanatory view showing a state during shaping of the CFRP material. FIG. 4 is an explanatory view showing a state in which the shaping of the CFRP material is completed. FIG. 5 is an explanatory diagram of the prepreg temperature, molding time, and prepreg viscosity in the molding process of the prepreg laminate. FIG. 6 is a schematic diagram of an apparatus that performs analysis using the analysis method according to the embodiment. FIG. 7 is a flowchart showing a processing procedure when performing analysis at the time of forming a CFRP material by the analysis method according to the embodiment. FIG. 8 is a perspective view of a test mold. FIG. 9 is a schematic view in plan view of the convex and concave portions of the test mold. FIG. 10 is an explanatory diagram of observation performed when verifying analysis conditions. FIG. 11 is a diagram illustrating a result of a test for verifying a physical property value used for analysis.

  Embodiments of an analysis method and an analysis apparatus for molding a carbon fiber reinforced plastic according to the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

Embodiment
1 to 4 are schematic views showing a process of molding a carbon fiber reinforced plastic to be analyzed using the analysis method according to the embodiment, and FIG. 1 is a state in which a CFRP material to be molded is put into a mold FIG. 2 is an explanatory view showing a state in which heat is transferred to the CFRP material, FIG. 3 is an explanatory view showing a state during the molding of the CFRP material, and FIG. 4 is a completed form of the CFRP material. It is explanatory drawing which shows a state. Here, shaping refers to a state in which the entire CFRP material is shaped along the shape of the upper and lower mold surfaces. The mold 40 shown in the figure is configured to be able to mold a CFRP material 30 that is a material of a workpiece made of CFRP (carbon fiber reinforced plastic), and in particular, CFRP made of a thermosetting resin. It is comprised so that the material 30 can be shape | molded appropriately. Specifically, the mold 40 has an upper mold 41 disposed on the relatively upper side and a lower mold 45 disposed on the lower side of the upper mold 41.

  The mutually opposing surfaces of the upper mold 41 and the lower mold 45 are formed as molding surfaces that come into contact with the CFRP material 30 during molding of the CFRP material 30 and mold the CFRP material 30. Specifically, the surface of the upper mold 41 that faces the lower mold 45 is formed as an upper mold molding surface 62, and the surface of the lower mold 45 that faces the upper mold 41 is formed as a lower mold molding surface 46.

  The upper mold forming surface 42 and the lower mold forming surface 46 have a shape that allows the CFRP material 30 to be formed into a desired shape by sandwiching the CFRP material 30 therebetween. For example, when a concave portion is formed on the lower mold forming surface 46, a portion of the upper mold forming surface 42 that faces the concave portion of the lower mold forming surface 46 is positioned with the CFRP material 30 interposed therebetween. It is formed in a convex shape that enters the concave portion of the molding surface 46. Thereby, when the CFRP material 30 is molded, the mold 40 deforms the CFRP material 30 with the convex portion of the upper mold molding surface 42 and the concave portion of the lower mold molding surface 46 so that the CFRP material 30 has a desired shape. Molding is possible.

  Further, a heater (not shown) that is a heating means for heating the CFRP material 30 is provided inside the lower mold 45. This heater is configured so that high-temperature machine oil can be circulated therein, and can transfer the heat of the machine oil to heat the CFRP material 30 when the CFRP material 30 is molded. . In addition, a heater other than what heats using high-temperature machine oil may be sufficient, for example, it may heat by raising temperature by electricity supply. Further, the heater may be disposed not only on the lower die 45 but also on the upper die 41.

  When molding the CFRP material 30 with the mold 40 configured in this way, the temperature of the lower mold 45 is first raised by the heater while the upper mold 41 and the lower mold 45 are separated from each other. Specifically, the temperature of the lower mold 45 is transmitted to the CFRP material 30, and the temperature of the lower mold 45 is raised to a temperature at which the CFRP material 30 is easily deformed.

  As the CFRP material 30 to be molded by the mold 40, a sheet-like material, that is, a so-called prepreg form, in which a carbon fiber is impregnated with a thermosetting resin in advance and used is used. The CFRP material 30 in which the prepregs are laminated is disposed on the lower mold forming surface 46 of the lower mold 45 that has been heated (FIG. 1). In this case, the CFRP material 30 in a normal temperature state is disposed with respect to the lower mold 45 whose temperature has been increased.

  Since the CFRP material 30 arranged on the lower mold forming surface 46 has a prepreg temperature 50 (see FIG. 5) lower than that of the lower mold 45, the heat of the lower mold 45 is transferred to the CFRP material 30 (FIG. 2). . That is, the heat of the lower mold 45 is transmitted to the CFRP material 30 from the portion in contact with the lower mold 45, and the prepreg temperature 50 is increased in the portion of the CFRP material 30 where the heat is transmitted. The heat transmitted to the CFRP material 30 in this way is transmitted to other portions of the CFRP material 30 by conduction, and the prepreg temperature 50 sequentially increases from the portion where the heat is transmitted. For this reason, the CFRP material 30 is separated from the portion of the CFRP material 30 where the prepreg temperature 50 is relatively high due to the transfer of heat from the lower die 45 and the contact portion between the CFRP material 30 and the lower die 45. As a result, the prepreg temperature 50 is unlikely to rise, and a low temperature portion 32 that is a portion having a relatively low prepreg temperature 50 is generated.

  In addition, the CFRP material 30 whose temperature has been increased by transferring the heat of the lower mold 45 has a prepreg viscosity 51 that decreases from the high temperature portion 31 at which the prepreg temperature 50 has been increased, and is likely to be deformed sequentially. That is, the CFRP material 30 is in a state where a portion that is easily deformed due to a temperature rise and a portion that is difficult to deform are mixed.

  When the heat of the lower mold 45 is transferred to the CFRP material 30, the region of the high temperature portion 31 expands, and when the portion that has been easily deformed expands to some extent, the upper mold 41 is moved in the direction of the lower mold 45. Is started (FIG. 3). The upper die 41 is configured to move in the direction of the lower die 45 by a hydraulic pressure generator or a pressing force generating means such as a gas spring or a coil spring, and generate a pressing force in the direction of the lower die 45. ing.

  When shaping the CFRP material 30, the upper mold 41 is moved in the direction of the lower mold 45 on which the CFRP material 30 is placed, and the upper mold forming surface 42 of the upper mold 41 is brought into contact with the CFRP material 30. As a result, the CFRP material 30 is sandwiched between the upper mold 41 and the lower mold 45. When the CFRP material 30 is molded, the upper mold 41 is further moved in the direction of the lower mold 45 while the upper mold molding surface 42 is in contact with the CFRP material 30 to apply a pressing force to the CFRP material 30. .

  The CFRP material 30 has a portion that is easily deformed by the heat transmitted from the portion that is in contact with the lower mold 45. By moving the upper mold 41 and applying a pressing force, the CFRP material 30 is deformed. Then, the number of parts that come into contact with the lower die 45 is newly increased, and the part that is easily deformed is further enlarged. That is, the CFRP material 30 sandwiched between the upper mold 41 and the lower mold 45 is deformed into a shape along the upper mold molding surface 42 and the lower mold molding surface 46 by the pressing force from the upper mold 41. In this way, the CFRP material 30 is deformed, and the portion that has not been in contact with the lower die 45 before the pressing force is applied also comes into contact with the lower die 45, so that the CFRP material 30 has a newly contacted portion. Heat is transferred from the lower mold 45. As a result, the CFRP material 30 is sequentially heated and the high temperature portion 31 spreads, and the CFRP material 30 is easily deformed sequentially from the heated portion.

  The CFRP material 30 that has been shaped by deforming into a shape along the upper mold forming surface 42 and the lower mold forming surface 46 starts to cure (FIG. 4). Specifically, the CFRP material 30 made of a thermosetting resin has a viscosity that once decreases due to the heat transmitted from the mold 40 and is likely to be deformed, and the prepreg temperature 50 further increases from there, and the chemical reaction of the resin proceeds. As a result, the curing of the resin starts and the curing of the CFRP material 30 starts. Since this curing reaction starts from a portion that has been in contact with the lower mold 45 immediately after being introduced into the CFRP material 30, the CFRP material 30 includes a high curing region 35 and a low curing region 36. Become.

  That is, when the CFRP material 30 is placed on the lower mold surface 46 of the lower mold 45 at the start of shaping of the CFRP material 30, the prepreg temperature 50 is increased by contacting the lower mold 45 and transferring heat. Curing of the CFRP material 30 starts from the beginning. The CFRP material 30 is cured from the portion where the prepreg temperature 50 starts to rise in this way, and the entire CFRP material 30 is cured as the temperature rises and time elapses. Thereby, the CFRP material 30 is cured in a shape formed by the upper mold forming surface 42 and the lower mold forming surface 46.

  Next, characteristics of the molding process of the CFRP material 30 will be described. FIG. 5 is an explanatory diagram of the prepreg temperature, molding time, and prepreg viscosity in the molding process of the prepreg laminate. The CFRP material 30 that is made of a thermosetting resin and is a prepreg laminate is formed by increasing the prepreg temperature 50 and curing the CFRP material 30. As shown in FIG. And changes depending on the molding time. The prepreg viscosity 51 shows a high correlation with the ease of deformation of the prepreg laminate. That is, the ease of deformation of the CFRP 30 changes in a form similar to FIG. 5 during the molding process.

  Specifically, the prepreg viscosity 51 shows a somewhat high value at room temperature. Then, at the initial stage of forming the prepreg laminate into the mold, the prepreg viscosity 51 rapidly decreases due to the temperature rise caused by the heat transferred from the lower mold 45, and the ease of deformation is rapidly improved. This prepreg temperature 50 at which the prepreg viscosity 51 rapidly decreases is referred to as a rapid softening temperature Ts.

  Next, the chemical reaction of the prepreg laminate progresses as the temperature rises and the time elapses, and the prepreg viscosity 51 once reduced rapidly increases to the softening end temperature Te. When the softening end temperature Te is exceeded, the rate of change of the prepreg viscosity 51 becomes small, the curing gradually proceeds, and finally the curing is completed after a certain time has elapsed. The softening end temperature Te here refers to the point at which the rate of change of the rapidly increasing prepreg viscosity 51 changes when the temperature of the prepreg laminate increases.

  Since the CFRP material 30 has these characteristics, each part of the CFRP material 30 that has been put into the mold and has the prepreg temperature 50 increased is deformed according to the prepreg viscosity 51 according to the prepreg temperature 50 and the molding time. It is easy to carry out, and different parts are deformed by the force applied from the mold 40.

  Here, the CFRP material 30 at the time of molding mold injection increases the prepreg temperature 50 due to the heat transmitted from the mold 40, but the heat is first transmitted from the part that touches the mold surface. The prepreg temperature 50 is not equal in each part. Therefore, the prepreg viscosity 51 is not uniform in each part of the CFRP material 30, and the ease of deformation is not uniform. Further, the state of the chemical reaction in each part of the CFRP material 30 also differs depending on the prepreg temperature 50 and the time during which heat is transferred, so that it differs between the part where the prepreg temperature 50 first rises and other parts. As described above, for a while after the CFRP material 30 is put into the mold, the ease of deformation of each part of the CFRP material 30 varies depending on the part.

  On the other hand, when the CFRP material 30 is molded, for example, in the vicinity of a portion where the radius of curvature is small when the plate-like CFRP material 30 is bent, the target shape is not completely formed, and wrinkles or the like may occur. is there. Thus, the shape after molding of the CFRP material 30 slightly different from the target shape can be derived by analyzing the deformation state at the time of molding of the CFRP material 30 using the analysis device. Next, this analysis apparatus will be described.

  FIG. 6 is a schematic diagram of an apparatus that performs analysis using the analysis method according to the embodiment. The analysis device 1 shown in FIG. 6 includes a processing unit 2, a storage unit 4, and an input / output unit 8, which are connected to each other and can exchange signals with each other. Among these, an input / output device 10 is connected to the input / output unit 8. The input / output device 10 is an input device 11 that is an input device that inputs data to the analysis device 1 such as a keyboard and a mouse, and an output device such as a display that displays the results of arithmetic processing performed by the analysis device 1. Display means 12 is used. Various information at the time of analyzing the CFRP material 30 can be input by the input means 11, and the input information and analysis results can be output by the display means 12.

  The processing unit 2 includes a CPU (Central Processing Unit) and the like, and can perform various arithmetic processes. Further, the storage unit 4 stores a computer program that can analyze the CFRP material 30 at the time of molding, that is, a computer program used in the analysis method according to the present embodiment. As this computer program, a well-known computer program that can input the data of the model to be analyzed and the information of the external force applied to the model and analyze the state of the model deformed by the external force by the finite element method is used. ing.

  The storage unit 4 in which the computer program is stored includes an HDD (Hard Disk Drive), a magneto-optical disk device, or a non-volatile memory such as a flash memory (a storage medium that can only be read such as a CD-ROM), , A volatile memory such as a RAM (Random Access Memory), or a combination thereof.

  Moreover, the said computer program may be what can implement | achieve the analysis at the time of shaping | molding of the CFRP material 30 with the combination with the computer program already recorded on the computer system. Further, the computer program for realizing the function of the processing unit 2 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into the computer system and executed, whereby the CFRP material 30 is recorded. Analysis during molding may be performed. Here, the “computer system” includes hardware such as an OS (Operating System) and peripheral devices.

  Next, a method for analyzing the deformation state of the CFRP material 30 at the time of molding by the analyzer 1 will be described. FIG. 7 is a flowchart showing a processing procedure when performing analysis at the time of forming a CFRP material by the analysis method according to the embodiment. When analysis is performed when the CFRP material 30 is molded, a computer program stored in the storage unit 4 and capable of analysis at the time of molding the CFRP material 30 is read into the work area of the storage unit 4 and executed. The computer program used in the analysis method according to the present embodiment performs analysis processing while performing interactive processing with the user. That is, for each process during the analysis process, the display unit 12 displays an instruction to input information and progress information of the analysis process, and the input unit 11 inputs various information necessary for the analysis.

  In this analysis process, first, the type of material to be analyzed is input (step ST101). Since the CFRP material 30 is a composite material composed of carbon fiber and synthetic resin, information indicating that the material to be analyzed is a composite material is input to the analysis apparatus 1.

  Next, the shape is captured (step ST102). Specifically, data on the shape after molding of the CFRP material 30, that is, data on a target shape when the CFRP material 30 is molded is input. As the data of this shape, for example, the data after molding of the CFRP material 30 is obtained by using the data after molding created by CAD (Computer Aided Design), and by importing the data created by CAD. Into.

  Next, the model is confirmed (step ST103). That is, the model data after molding based on the shape data after molding of the CFRP material 30 taken in using data created by CAD, etc. is confirmed, and the model data used for analysis becomes appropriate data. Adjust. For example, the thickness of the CFRP material 30, that is, the thickness of the shape after molding is set to an appropriate value, or the orientation of the model after molding with respect to the orientation of the material before molding of the CFRP material 30 is generated with the material at the time of molding. Make adjustments such as adjusting the relative orientation of the object.

Next, information on the surface of the material to be molded is input (step ST104). Specifically, detailed information about the CFRP material 30 to be molded, such as a physical property value, thickness, and fiber direction of the CFRP material 30 that is a material to be molded, is input. Among these, as physical property values, density (kg / mm ³ ), Young's modulus (GPa), shear elastic modulus (GPa), and Poisson's ratio are used. In the case of the CFRP material 30 made of a thermosetting resin, density ρ = 1.8 × 10 ⁻⁶ kg / mm ³ , Young's modulus (fiber direction) E1 = 130 GPa, Young's modulus (fiber orthogonal direction) E2 = 5 GPa , Shear modulus G = 2GPa, Poisson's ratio ν = 0.3 is used. That is, in the carbon fiber reinforced plastic, the strength differs between the direction of the carbon fiber and the direction orthogonal to the direction of the carbon fiber, so the Young's modulus is Young's modulus E1 = 130 GPa in the fiber direction and Young in the fiber orthogonal direction. Two types of values with a rate E2 = 5 GPa are used.

  Next, analysis conditions are set (step ST105). Specifically, as the analysis conditions, the movement of the CFRP material 30 during the molding of the CFRP material 30 is set, and the analysis conditions including the force applied to the CFRP material 30 and the movement of the CFRP material 30 during the molding of the CFRP material 30 are set. input. Specifically, the direction in which the mold 40 moves during molding, that is, the direction of the pressing force applied from the mold 40 to the CFRP material 30, the movable part of the CFRP material 30 when the pressing force is applied to the CFRP material 30, The movement of the CFRP material 30 during molding, such as the movable timing and stop timing, is set. That is, at the time of forming the CFRP material 30, the location where the pressing force is applied and the direction thereof, and the portion of the CFRP material 30 that is moved by the pressing force and the way of movement are set. Further, in the setting of the analysis conditions, detailed setting of analysis such as a calculation pitch at the time of analysis is also performed.

  Next, analysis is started (step ST106). That is, the input material type (step ST101), the target shape at the time of molding (step ST102), the data appropriately adjusted as data used for analysis (step ST103), and the information on the surface of the material (step) Based on ST104), analysis at the time of forming the CFRP material 30 is performed according to the set analysis conditions (step ST105).

  That is, based on the computer program stored in the storage unit 4 and capable of analyzing the CFRP material 30 at the time of molding, and each data input by the input means 11, the processing unit 2 performs arithmetic processing, and the CFRP material Analysis at the time of forming 30 is performed. The analysis result derived by performing arithmetic processing in the processing unit 2 is output by the display means 12. When outputting by the display means 12, the shape after molding obtained by analysis is output as a shape model that can be visualized or output as numerical data. Thereby, the analysis result at the time of shaping | molding of the CFRP material 30 can be obtained.

  However, when the CFRP material 30 is molded, the ease of deformation differs from site to site as described above. For this reason, even if analysis is performed using shape data after molding, information on the material to be molded, and how the CFRP material 30 moves due to the pressing force at the time of molding the CFRP material 30, It is difficult to analyze and predict an accurate shape after molding including fine shapes such as the above. Therefore, the inventors conducted tests on conditions under which the shape after molding can be accurately analyzed and predicted in order to accurately predict the shape of the CFRP material 30 during molding. Next, this test will be described.

  In the test, the result of actually molding the CFRP material 30 is compared with the analysis result when the analyzer 1 analyzes the state of the CFRP material 30 during molding. As test conditions, the CFRP material 30 to be molded is a prepreg laminate having a size of 320 mm × 250 mm and a thickness of 0.7 mm (0.14 mm × 5 layers).

  FIG. 8 is a perspective view of a test mold. The test mold 60, which is a mold used for the test, has an upper mold 61 and a lower mold 65 in the same manner as the mold 40 used in normal molding of the CFRP material 30, and the upper mold 61 is on the lower side. By moving, the CFRP material 30 can be formed. The test mold 60 is configured so as to be formed so as to form a substantially rectangular convex portion.

  Specifically, in the upper mold 61, a convex portion 63 that protrudes in the direction of the lower mold 65 in a substantially rectangular shape is formed on the upper mold forming surface 62 that faces the lower mold 65. In FIG. 8, for the sake of convenience, the upper mold 61 is illustrated with the vertical direction reversed. In the lower mold 65, a recess 67 that is recessed in a substantially rectangular shape is formed on a lower mold forming surface 66 that faces the upper mold 61. The concave portion 67 is substantially rectangular in shape when viewed in the vertical direction and approximates to the convex portion 63 of the upper mold 61 and is slightly larger than the convex portion 63, and the depth is equal to the height of the convex portion 63. It is the same depth. The test mold 60 has an upper mold 61 and a lower mold 65 in a state where the upper mold molding surface 62 and the lower mold molding surface 66 are opposed to each other, and the CFRP material 30 is interposed between the upper mold 61 and the lower mold 65. The CFRP material 30 is molded by applying a pressing force to the CFRP material 30 by bringing them close to each other.

  FIG. 9 is a schematic view in plan view of the convex and concave portions of the test mold. The convex portion 63 and the concave portion 67 formed in a substantially rectangular shape in plan view are different in the size of the four corner portions. Specifically, the first corner 71 which is one of the four corners has a radius of 10 mm. Similarly, the second corner 72 has a radius of 20 mm and the third corner 73 has a radius. Is 30 mm, and the radius of the fourth corner 74 is 40 mm.

  In this test, the CFRP material 30 is molded using the test mold 60 under conditions of a molding speed of 10 mm / sec, a pressing force of 150 ton, and a pressing time of 15 minutes. In the analysis apparatus 1, the same conditions were used, and a plurality of analyzes were performed with different physical property values, and each analysis result was compared with the actual molding state.

  Here, the inventors consider the state of the CFRP material 30 at the time of molding. Since the CFRP material 30 at the time of molding is not easily deformable, the physical property values of one state at the time of molding are used. Even if analysis was performed, the shape obtained by the analysis was considered to be different from the actually molded shape. For this reason, the inventors perform analysis at the time of molding using a value at a certain degree of curing that is neither a physical property value of the CFRP material 30 before curing at normal temperature nor a physical property value in a state where curing is completed. Was assumed to be optimal. The degree of curing is a value indicating the degree of crosslinking of the polymer resin as a base material, that is, the degree of curing reaction, and is generally indicated by a value of 0 to 100%. For this reason, the test on the conditions that can accurately predict the shape after molding is intended to verify that the physical property value when the percentage value of the degree of cure is appropriate as the analysis condition. Went as.

In the test, the physical property value of the CFRP material 30 at a temperature equal to or higher than the degree of cure of 50% and the softening end temperature Te (see FIG. 5) is assumed to be an appropriate assumed value for use in the analysis. That is, in the test, as assumed values suitable for use in the analysis, density ρ = 1.8 × 10 ⁻⁶ kg / mm ³ , Young's modulus (fiber direction) E1 = 130 GPa, Young's modulus (fiber orthogonal direction) E2 = Values of 5 GPa, shear modulus G = 2 GPa, Poisson's ratio ν12 = 0.3 are used.

  On the other hand, four types of set values are used as the physical property values for analysis to be compared with the analysis results at the assumed values. These set values are combinations of hypothesized values that are halved or doubled. Specifically, the setting value 1 and the setting value 2, which are two of the four types of setting values, change the Young's modulus E2 in the fiber orthogonal direction from the assumed value, and the Young's modulus in the fiber orthogonal direction of the assumed value For E2 = 5 GPa, 2.5 GPa (set value 1) and 10 GPa (set value 2), respectively. Further, the remaining set values of the four types of set values, ie, the set value 3 and the set value 4, are obtained by changing the shear elastic modulus G from the assumed value, and for the assumed value of the shear elastic modulus G = 2GPa, respectively. Set to 1 GPa (set value 3) and 4 GPa (set value 4).

  In this test, the result of analysis by the analysis apparatus 1 using these assumed values and setting values 1 to 4 and the acquired product obtained by actually molding the CFRP material 30 with the test die 60. By comparing the shapes, it was verified whether or not the assumed values are appropriate as the physical property values used in the analysis.

  FIG. 10 is an explanatory diagram of observation performed when verifying analysis conditions. The analysis conditions are verified based on the number of wrinkles generated during molding. Specifically, when molding the CFRP material 30, wrinkles are likely to occur in places where there is a lot of deformation from the material, so by comparing the number of wrinkles that occur near the corners after molding, Verify the analysis conditions. That is, the wrinkle 85 generated in the vicinity of each of the first corner 81, the second corner 82, the third corner 83, and the fourth corner 84 of the acquired product 80 molded by the test mold 60, and the analysis device 1, wrinkles generated in the vicinity of the first corner portion 21, the second corner portion 22, the third corner portion 23, and the fourth corner portion 24 of the analysis shape 20 analyzed using the assumed values and the setting values 1 to 4. 25 is compared. In addition, the number of these wrinkles 25 and 85 uses the number of wrinkles concerning the curved part in a corner | angular part.

  As described above, the wrinkles 25 at the corners of the respective analysis shapes 20 analyzed using the assumed values and the setting values 1 to 4 are compared with the wrinkles 85 at the corners of the acquired product 80 formed by the test mold 60. Thus, among the assumed values and the set values 1 to 4, an analysis condition closest to the acquired product 80 obtained by actually forming the CFRP material 30 is derived.

  FIG. 11 is a diagram illustrating a result of a test for verifying a physical property value used for analysis. As a result of the test, in the acquired product 80 in which the CFRP material 30 is actually molded, the number of wrinkles 85 is three for the first corner 81, four for the second corner 82, three for the third corner 83 and the second corner 82. The four corners 84 became six. On the other hand, in the analysis shape 20 analyzed using the set values 1 to 4 which are physical property values different from the assumed values, any one of the four corners or all the wrinkles 25 of the four corners. Is different from the number of wrinkles 85 at the corners of the corresponding acquired product 80. Thus, the number of wrinkles did not match between the acquired product 80 and the set values 1 to 4, and the analysis shape 20 was different in detail from the acquired product 80.

  On the other hand, in the analysis shape 20 analyzed using the assumed value which is a physical property value of the CFRP material 30 at a temperature equal to or higher than the curing degree 50% and the softening end temperature Te, the number of the wrinkles 25 is the number of the first corner portions 21. The number of the third corners 22 is four, the number of the third corners 23 and the number of the fourth corners 24 is six. As described above, the number of wrinkles was the same between the acquired product 80 and the assumed value, and the analysis shape 20 was the same as the acquired product 80 in the details. That is, the analysis shape 20 approximated to the acquired product 80 can be obtained with high accuracy by performing analysis at the time of molding of the CFRP material 30 using the physical property values of the CFRP material 30 having a curing degree of 50%.

  Since these results were obtained as analysis tests at the time of forming the CFRP material 30, it is preferable that the analysis apparatus 1 is equipped with a function capable of realizing this analysis. Specifically, the analysis apparatus 1 includes a physical property value acquisition unit that acquires a physical property value of the CFRP material 30 having a degree of cure of about 50% when the temperature of the CFRP material 30 is increased and curing is progressing. Is preferred. For example, the processing unit 2 is used as the physical property value acquisition unit. When performing analysis at the time of molding of the CFRP material 30 with the analysis device 1, first, a target shape when molding the CFRP material 30 (step ST102), information on the CFRP material 30 (step ST104), CFRP An analysis condition (step ST105) including the force applied to the CFRP material 30 and the movement of the CFRP material 30 when the material 30 is molded is input by the input unit 11.

  Further, the processing unit 2 acquires physical property values of the CFRP material 30 having a degree of cure of about 50%. As a method for obtaining such a physical property value, for example, a curing degree deriving unit that derives a physical property value of the CFRP material 30 having a curing degree of about 50% based on the physical property value of the CFRP material 30 having a curing degree of 100% is analyzed. This is realized by preparing for 1. The degree-of-curing degree derivation unit is configured by storing in the storage unit 4 the physical property values of the CFRP material 30 having a degree of curing of 50% with respect to the physical property values of the CFRP material 30 having the degree of curing of 100% as a database. In this case, when inputting the physical property value of the CFRP material 30 when inputting the information of the CFRP material 30, the physical property value of the CFRP material 30 having a curing degree of 100% is input.

  The processing unit 2 uses the database stored in the storage unit 4 based on the physical property value of the CFRP material 30 having a curing degree of 100% input by the input unit 11, and the physical property value of the CFRP material 30 having a curing degree of approximately 50%. Is obtained by deriving Further, the processing unit 2 uses the CFRP material 30 based on the information on the CFRP material 30 including the physical property value of the CFRP material 30 having a degree of cure of about 50%, the shape to be targeted at the time of molding, and the analysis conditions. Analyzes during molding. Thereby, the analysis shape 20 approximated to the acquired product 80 can be obtained with high accuracy.

  In the analysis method at the time of molding of the CFRP material 30 according to the above-described embodiment, when performing the analysis at the time of molding of the CFRP material 30, the physical properties of the CFRP material 30 at a temperature equal to or higher than the curing degree 50% and the softening end temperature Te. By performing the analysis using the values, it is possible to obtain an analysis shape 20 that is approximated with high accuracy to the shape that is actually formed. That is, the physical property value of the CFRP material 30 at a temperature of the curing degree 50% and the softening end temperature Te or higher is compared with the molding of the CFRP material 30 in which the prepreg temperature 50 and the deformability are not uniform depending on the part at the time of molding. By using and analyzing, it is possible to easily and accurately analyze the prepreg temperature 50 and the assumption that the ease of deformation is uniform. Thereby, the consistency of the analysis shape 20 derived | led-out by analysis and the acquired product 80 at the time of actually shape | molding the CFRP material 30 can be improved. As a result, it is possible to analyze and predict the shape at the time of molding with high accuracy and contribute to the improvement of the design accuracy of the molding die.

  In addition, the target shape when the CFRP material 30 is molded, the information about the CFRP material 30, and the analysis conditions are input to the analysis apparatus 1 that performs analysis processing by a computer program. Since the analysis is performed by the analysis apparatus 1, the analysis can be easily performed with high accuracy. As a result, the shape at the time of molding can be analyzed and predicted with higher accuracy.

  Moreover, in the analysis apparatus 1 at the time of molding of the CFRP material 30 according to the present embodiment, when performing the analysis at the time of molding of the CFRP material 30, a physical property value of the CFRP material 30 having a degree of cure of about 50% is acquired. Since the analysis is performed using the values, the consistency between the analysis shape 20 derived by the analysis and the acquired product 80 when the CFRP material 30 is actually formed can be enhanced. As a result, it is possible to analyze and predict the shape at the time of molding with high accuracy and contribute to the improvement of the design accuracy of the molding die.

[Modification]
In the analysis apparatus 1 described above, the storage unit 4 constituting the curing degree deriving unit stores the physical property values of the CFRP material 30 having a curing degree of 50% with respect to the physical property values of the CFRP material 30 having a curing degree of 100% as a database. However, the curing degree deriving unit may be configured other than this. For example, the storage unit 4 stores a function for calculating the physical property value of the CFRP material 30 having a curing degree of 50% from the physical property value of the CFRP material 30 having a curing degree of 100%, and the curing degree 100 input by the input unit 10. % Physical property value and this function may be used to calculate a physical property value with a curing degree of 50%. The method of deriving the physical property value of the CFRP material 30 having a curing degree of 50% is not limited as long as the physical property value of the CFRP material 30 having the curing degree of 100% input by the input unit 11 can be derived. .

  Further, when the processing unit 2 acquires the physical property value of the CFRP material 30 having a curing degree of about 50%, the physical property value of the CFRP material 30 having a curing degree of about 50% may be directly acquired. For example, when inputting information on the CFRP material 30 by the input means 11, the display means 12 performs a display prompting the user to input a physical property value of the CFRP material 30 having a degree of cure of about 50%, and the CFRP material having a degree of cure of about 50%. Analysis may be performed after the input of 30 physical property values. As described above, by directly obtaining the physical property value of the CFRP material 30 having a degree of cure of about 50%, it is not necessary to derive the physical property value, and therefore, analysis can be easily performed.

  In addition, it is preferable that a database of physical property values stored in the storage unit 4 is appropriately added. In other words, if there is no physical property value of 50% cure degree of the CFRP material 30 to be analyzed on the database, the physical property value of 50% cure rate and the physical property value of 100% cure rate are prompted. These input physical property values may be added to the database. Thus, by repeatedly performing the analysis, the data amount of the database is accumulated, and the shape at the time of molding can be analyzed and predicted with higher accuracy.

  Further, the mold 40 for molding the CFPR material 30 may be other than the above-described form, and the shape for molding the CFPR material 30 may be other than the above-described shape. Regardless of the shape to be molded, when the CFPR material 30 is analyzed at the time of molding, the physical property value near 50% of the degree of cure of the CFPR material 30 is used, so that the accuracy of the actual molding of the CFPR material 30 is high. Can be analyzed.

  Further, the analysis of the shape of the CFPR material 30 at the time of molding may be performed by performing correction using a coefficient. That is, the prepregs that make up the CFRP material 30 may have slightly different physical property values depending on the manufacturer that manufactures the prepreg, even if they have the same grade. Even if the same prepreg is used, the molding results may differ slightly depending on conditions such as temperature, humidity, pressure, and time. In consideration of such cases, in order to improve the accuracy of the analysis result, at the time of analysis, the curing degree and the physical property value of the physical property value used for the analysis may be corrected by a coefficient. Specifically, a coefficient according to the manufacturer, conditions such as temperature and humidity is set in advance, and at the time of molding analysis, a coefficient according to the actual molding conditions is used to determine the degree of curing using the physical property value, or The physical property value of the degree of cure of 50% may be corrected and the molding may be analyzed. Thereby, the analysis suitable for the conditions at the time of actual molding can be performed, and the shape at the time of design can be predicted with higher accuracy.

  Further, the physical property values used in the analysis method described above may be other than the values used in the above embodiment. If the physical property value used in the analysis method is the material property value of the material whose temperature is increased by about 50% due to the temperature rise of the material made of carbon fiber reinforced plastic of thermosetting resin, it is described above. It may be other than the value. By performing the analysis using the physical property value of the material having a degree of cure of around 50%, the shape at the time of molding can be predicted with high accuracy.

DESCRIPTION OF SYMBOLS 1 Analysis apparatus 2 Processing part 4 Memory | storage part 8 Input / output part 10 Input / output apparatus 11 Input means 12 Display means 20 Analysis shape 21, 71, 81 1st corner part 22, 72, 82 2nd corner part 23, 73, 83 1st Triangle portion 24, 74, 84 Fourth corner portion 25, 85 Wrinkle 30 CFRP material 31 High temperature portion 32 Low temperature portion 35 High cure region 36 Low cure region 40 Mold 41, 61 Upper die 42, 62 Upper mold forming surface 45, 65 Lower mold 46, 66 Lower mold forming surface 50 Prepreg temperature 51 Prepreg viscosity 60 Test die 63 Convex part 67 Concave part 80 Acquired product

Claims (6)

The target shape when molding a material made of carbon fiber reinforced plastic of thermosetting resin,
Information on the material including physical property values of the material at a degree of curing near 50% when the temperature of the material is rising and curing is progressing;
An analysis condition including a force applied to the material at the time of molding the material and a movement of the material;
The analysis method at the time of molding of the carbon fiber reinforced plastic is characterized in that the analysis at the time of molding the material is performed on the basis of A procedure for entering the target shape when molding a material made of carbon fiber reinforced plastic,
A procedure for inputting information of the material;
A procedure for inputting an analysis condition including a force applied to the material at the time of molding the material and a movement of the material;
Based on the target shape at the time of molding, information on the material, and the analysis conditions, a procedure for performing analysis at the time of molding the material,
In the analysis method when molding carbon fiber reinforced plastic containing
When the material is a thermosetting resin, in the procedure of inputting the information on the material, the physical property value of the material near 50% of the degree of curing when the temperature of the material is rising and curing is progressing. An analysis method for molding a carbon fiber reinforced plastic characterized by inputting. The target shape when forming the material, the information on the material, and the analysis conditions are input to an analysis device that performs analysis processing at the time of forming the material by a computer program,
The analysis method during molding of the carbon fiber reinforced plastic according to claim 2, wherein the analysis during molding of the material is performed by the analysis device. Input means capable of inputting an analysis condition including a target shape when molding a material made of carbon fiber reinforced plastic, information on the material, force applied to the material when the material is molded, and movement of the material When,
A physical property value acquisition unit for acquiring a physical property value of the material at a degree of curing of about 50% when the temperature of the material is rising and curing is progressing;
Based on the target shape at the time of molding, the material information including the physical property value of the material having a degree of cure of about 50% acquired by the physical property value acquisition unit, and the analysis condition, A processing unit for performing analysis;
An analysis apparatus for molding carbon fiber reinforced plastic characterized by comprising: A curing degree deriving unit for deriving a physical property value of the material having a curing degree of about 50% based on a physical property value of the material having a curing degree of 100%;
The physical property value acquiring unit acquires the physical property value of the material having a curing degree of about 50% from the physical property value of the material having a curing degree of 100% input by the input unit by deriving the cured property value by the curing degree deriving unit. The analysis apparatus at the time of shaping | molding of the carbon fiber reinforced plastics of Claim 4 characterized by these.   5. The carbon fiber reinforced plastic according to claim 4, wherein the physical property value acquisition unit prompts an input of a physical property value of the material having a curing degree of about 50% when the information of the material is input by the input unit. Analysis device at the time of molding.

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