Method of predicting joined place of injection joining metal member-resin member composite

Abstract

To provide a method of predicting a joined place of a metal member-resin member composite from resin flow analysis in the metal member-resin member composite molded by injection joining.SOLUTION: Provided is a method of predicting a joined place of an injection joining metal member-resin member composite, that contrasts a calculated viscosity when a resin obtained by resin flow analysis of an injection joining metal-resin test piece having joinability and airtightness comes into contact with a metal, and each predicted viscosity when a resin obtained by the resin flow analysis of respective partitions into which a joined portion in the injection joining metal member-resin member composite is partitioned comes into contact with the metal member.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for predicting the joints of injection-bonded metal member-resin member composites using injection molding resin flow analysis. More specifically, the present invention predicts the joints of metal members and resin members in metal member-resin member composites, which have been difficult to predict until now, from data obtained from resin flow analysis, and further enables support for the design of parts, mold design, and support for changing molding conditions for composites, thereby making it possible to improve design efficiency and reduce the number of prototypes. [Background technology]

[0002] In recent years, metal-resin composite technology has been attracting attention because it allows for the design of parts that take advantage of the advantages of both metal and resin. Methods proposed for combining metal and resin include mechanical joining, adhesive joining, and injection joining. A typical mechanical joining method is screw fastening, which provides high joint strength but has limited design freedom and is less productive due to the additional screw fastening process. Adhesive joining provides greater design freedom than mechanical joining but has lower joint strength and is less productive due to the additional adhesive joining process. On the other hand, injection joining, typically a method involving insert molding of surface-treated metal, is attracting attention due to its high productivity and design freedom achieved by integrally molding metal and resin.

[0003] In recent years, computer-aided engineering (CAE) analysis methods have been widely used in injection molding. For example, methods have been proposed that use flow analysis to predict the position and width of weld lines that will occur in molded products (see, for example, Patent Document 1), and that combine measurement results from test pieces with flow analysis to predict the shrinkage rate of a desired resin molded product (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3870766 [Patent Document 2] Patent No. 3889587 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the methods proposed in Patent Documents 1 and 2, no consideration or proposal has been made regarding a metal member-resin member composite by injection joining.

[0006] Therefore, the present invention aims to provide a method for predicting the joining points at the joints between metal members and resin members in a metal member-resin member composite formed by injection joining, using injection molding resin flow analysis, a method for supporting the design of molds, parts, etc., and an efficient method for manufacturing an injection-joined metal member-resin member composite. [Means for solving the problem]

[0007] As a result of intensive research into solving the above problems, the inventors discovered that injection molding resin flow analysis including specific steps can predict the joining points of injection-bonded metal component-resin component composites, leading to the completion of the present invention.

[0008] In other words, the present invention relates to a method for predicting the joints of an injection-bonded metal member-resin member composite, which comprises dividing the joint in the injection-bonded metal member-resin member composite into multiple parts and comparing the calculated viscosity of the resin when it comes into contact with the metal, obtained from resin flow analysis of an injection-bonded metal-resin test piece that has bondability and airtightness, with the predicted viscosity of the resin when it comes into contact with the metal member, obtained from resin flow analysis of each part.

[0009] The present invention will be described in detail below.

[0010] The method for predicting a joint in an injection-bonded metal component-resin component composite of the present invention predicts a joint between a metal component and a resin component using viscosity obtained by resin flow analysis. The method divides the joint of the injection-bonded metal component-resin component composite into multiple sections, predicts the viscosity of the molten resin in each section when it contacts the metal component using resin flow analysis, and compares the predicted viscosity with the calculated viscosity of the molten resin in an injection-bonded metal-resin test piece with reference bondability and airtightness when it contacts the metal. This predicts whether or not a joint will be formed in each section of the injection-bonded metal component-resin component composite. The bondability of the joint between the metal component and the resin component is significantly affected by the viscosity of the molten resin when it contacts the metal, and lower viscosity tends to result in better bondability. The method for predicting a joint in an injection-bonded metal component-resin component composite of the present invention predicts the bondability of the joint by comparing the calculated viscosity of the injection-bonded metal-resin test piece with the calculated viscosity of the injection-bonded metal-resin test piece with reference bondability and airtightness, thereby predicting the jointability and predicting the section that will become the joint.

[0011] A flowchart is shown in Figure 1 as a schematic diagram for efficiently explaining the method of predicting the bonded portion of an injection-bonded metal member-resin member composite of the present invention. For the sake of convenience, this flowchart shows the analysis of viscosity when contacting metal in a metal-resin joint using resin flow analysis by calculating the viscosity using an injection-bonded metal-resin test piece and analyzing the predicted viscosity using an injection-bonded metal member-resin member composite, and further shows each of these as basic steps, and does not exclude the improvement of efficiency or addition of functions of the present invention, such as the continuation or integration of each step or the addition of other steps.

[0012] Hereinafter, the method of predicting the joining location of an injection-bonded metal member-resin member composite of the present invention will be described in detail with reference to FIG.

[0013] Calculated viscosity for injection-bonded metal-resin test specimens The calculated viscosity used as the basis for predicting the bonding location of a joint in an injection-bonded metal component-resin component composite can be calculated by resin flow analysis during testing and molding using an injection-bonded metal-resin test piece. For example, the viscosity when the resin comes into contact with the joint can be determined as the calculated viscosity through the following steps: Step 1: evaluate the bondability and airtightness of the injection-bonded metal-resin test piece and identify the bonding location at the joint; Step 2: create a 3D model of the injection-bonded metal-resin test piece that has bondability and airtightness and set the resin flow analysis data extraction points for the joint; Step 3: perform a resin flow analysis based on the molding conditions of the injection-bonded metal-resin test piece and extract flow data at each resin flow analysis data extraction point; and Step 4: calculate the viscosity when the resin comes into contact with the metal from the flow analysis data for the joint that has bondability and airtightness.

[0014] Step 1 of identifying the joint location of the injection-bonded metal-resin test piece involves evaluating the bondability and airtightness of the injection-bonded metal-resin test piece and identifying the joint location at the joint. The metal material, metal processing method, and resin material used for the test piece are the same as, and preferably identical to, the materials that ultimately constitute the actual part, the injection-bonded metal-resin composite that is the target of prediction. The shape of the test piece is not particularly limited as long as it can be injection molded, and a simple structure is preferable, since bondability and airtightness will be evaluated after the test piece is molded. The molding conditions for the test piece can be selected according to the resin material used and the injection-bonded metal-resin composite. The bondability and airtightness of the test piece can be confirmed by tests such as a peel test and an airtight test. In step 1, the joints at the joints of test pieces whose bondability and airtightness have been confirmed can be evaluated by, for example, observing the joint on the metal side of the test piece after peeling the metal and resin, and checking whether or not the resin remains. By identifying the areas where the resin remains as metal-resin joints and areas where the resin does not remain as metal-resin non-joints, the joints in the test piece can be specified.

[0015] Step 2 of setting extraction points for resin flow analysis data of the joint between injection-bonded metal and resin test piece involves, for example, creating a 3D model of the test piece, and setting extraction points for extracting resin flow data through resin flow analysis at the joint between the metal and resin in the created 3D model. To create the 3D model, commercially available software such as CATIA (trade name) or SOLIDWORKS (trade name) from Dassault Systemes can be used. It is preferable to set more extraction points, as this improves the prediction accuracy of the joint, and more efficient predictions are possible, specifically 1 to 16 points / mm. 2 It is preferable that:

[0016] Step 3, which extracts flow data at each resin flow analysis data extraction point, involves performing a resin flow analysis based on the molding conditions of the injection-bonded metal-resin test piece and extracting the flow data at the extraction point. The resin flow analysis can be performed using resin flow analysis simulation software with the function of extracting resin flow data at the extraction point, such as commercially available software like Moldex3D (product name) from CoreTech Systems. The extracted flow data can also include the resin temperature and shear rate when the resin comes into contact with the metal, in order to calculate the viscosity when the resin comes into contact with the metal.

[0017] Step 4, which calculates the calculated viscosity (the viscosity at the time of resin contact with metal), can be calculated using the extracted resin temperature and shear rate data and the shear rate dependency of the melt viscosity of the resin being used. Regarding the shear rate dependency of melt viscosity, for example, CoreTech System's Moldex3D (product name), material data can be checked for registered resins, and the shear rate dependency of melt viscosity can be determined from that material data. At the same time, various coefficients related to the shear rate dependency of melt viscosity can be checked, and these coefficients can be used to calculate the viscosity from the resin temperature and shear rate. For resins not registered in the resin flow analysis simulation software, the shear rate dependency of melt viscosity can be calculated by measuring the shear rate dependency of melt viscosity. The viscosity at the time of resin contact at the joint of the test specimen can then be determined, and this viscosity becomes the calculated viscosity used as the standard for developing bondability and airtightness.

[0018] Predicted viscosity of injection-bonded metal-resin composites When predicting the joint location of an injection-bonded metal component-resin component composite, the predicted viscosity at each section of the joint can be calculated by resin flow analysis of the injection-bonded metal component-resin component composite. The prediction method can be similar to the procedure for calculating the viscosity for the injection-bonded metal-resin test piece described above. For example, Step 2 involves creating a 3D model of the injection-bonded metal component-resin component composite, segmenting the joint, and setting resin flow analysis data extraction points. Step 3 involves performing resin flow analysis based on the molding conditions for the injection-bonded metal component-resin component composite and extracting flow data at each resin flow analysis data extraction point. Step 4 involves predicting the viscosity of each section when the resin contacts the metal component using the flow analysis data for each extraction point of the segmented joint. Note that the expression "Steps 2-4" does not necessarily mean that these steps are the same as steps 2-4 in calculating the viscosity using an injection-bonded metal-resin test piece. These steps are simply referred to as "Steps 2-4" for convenience, as the methods are similar. It is not intended to negate the use of "Steps 5-7."

[0019] Step 2, which divides the joint of the injection-bonded metal member-resin member composite and sets extraction points for resin flow analysis data, involves, for example, creating a 3D model of the composite, dividing the joint between the metal member and the resin member of the created 3D model into multiple parts, and setting extraction points for extracting resin flow data by resin flow analysis at each divided part. To create the 3D model, commercially available software such as CATIA (trade name) from Dassault Systemes or SOLIDWORKS can be used. Specifically, 1 to 16 points / mm is used, as this allows for more efficient predictions. 2 In addition, since more efficient prediction is possible, the sampling points are preferably 1 to 16 points / mm. 2 It is preferable that:

[0020] Step 3, extracting resin flow analysis data for each sample point of the divided joint, involves performing resin flow analysis under molding conditions for the injection-bonded metal-resin composite, preferably the same molding conditions as for the injection-bonded metal-resin test specimen, to extract flow data at the sample points. This resin flow analysis can be performed using, for example, resin flow analysis simulation software capable of extracting resin flow data at sample points, such as commercially available software like Moldex3D from CoreTech Systems. Extracted flow data can include the resin temperature and shear rate when the resin contacts the metal in each fraction, in order to calculate the viscosity of the resin when it contacts the metal.

[0021] Step 4, in which the predicted viscosity is calculated for each fraction when the resin contacts the metal component, can be calculated using the extracted resin temperature and shear rate data and the shear rate dependency of the melt viscosity of the resin being used. Regarding the shear rate dependency of melt viscosity, for example, CoreTech System's Moldex3D (product name), the material data can be checked for registered resins, and the shear rate dependency of melt viscosity can be determined from that material data. At the same time, various coefficients related to the shear rate dependency of melt viscosity can be checked, and these coefficients can be used to calculate viscosity from the resin temperature and shear rate. For resins not registered in the resin flow analysis simulation software, the shear rate dependency of melt viscosity can be calculated by measuring the shear rate dependency of melt viscosity.

[0022] Then, in step 5, the calculated viscosity of the injection-bonded metal-resin test piece is compared with the predicted viscosity of the divided joint of the injection-bonded metal member-resin member composite, and the joining action of the divided joint of the injection-bonded metal member-resin member composite can be predicted. In this case, as an example of a criterion, a method of predicting the joining location by predicting and judging that a section where the calculated viscosity is greater than or equal to the predicted viscosity is a section where the metal member and the resin member are joined can be used.

[0023] Furthermore, in the method of predicting the joints of an injection-bonded metal member-resin member composite of the present invention, if it can be determined by predicting the joints at the joints of the injection-bonded metal member-resin member composite that no paths through which gases, liquids, etc. can pass have been formed, it becomes possible to predict airtightness, and it is predicted that such an injection-bonded metal member-resin member composite will also have excellent airtightness.

[0024] The metal materials constituting the injection-bonded metal-resin test specimens and injection-bonded metal member-resin member composites of the present invention may be any metal, such as carbon steel, gold, silver, iron, iron alloys, copper, copper alloys, aluminum, aluminum alloys, magnesium, magnesium alloys, titanium, titanium alloys, and stainless steel. The metal surfaces may also be physically and / or chemically treated, such as by sandblasting, liquid honing, or laser machining, or by anodizing or chemical treatment with an acid or alkali aqueous solution. Resin materials include polyphenylene sulfide, polyamide, polybutylene terephthalate, polyethersulfone, polysulfone, polyacetal, polyethylene naphthalate, liquid crystal polymers, polycarbonate, and mixtures thereof.

[0025] The method for predicting joints in injection-bonded metal component-resin component composites of the present invention can predict the bondability and even airtightness of injection-bonded metal component-resin component composites. If unfavorable results are obtained, changes to the mold design (resin gate position, number of resin gates, resin gate size, product shape, etc.) or molding conditions (molten resin temperature, injection pressure, mold temperature, etc.) can be made to create a manufacturing method for injection-bonded metal component-resin component composites with excellent performance and productivity. Furthermore, by repeating predictions after adding or taking these changes into account, a more accurate joint prediction method can be achieved. Furthermore, by combining this method with a mold design support method, a more efficient mold design support method can be created. [Effects of the Invention]

[0026] According to the present invention, it is possible to predict the joining points of metal and resin members in injection-bonded metal member-resin member composites formed by injection bonding using injection molding resin flow analysis, from data obtained from resin flow analysis. By predicting the joining points of metal and resin members, it is possible to predict the joining and airtightness at the design stage, which previously required the mold to be constructed and checked on a prototype after the part was designed, making it possible to improve design efficiency and reduce the number of prototypes, making it of extremely high industrial value. [Brief explanation of the drawings]

[0027] [Figure 1] ;A diagram showing a schematic flow chart of a method for predicting the joining points of an injection-bonded metal member-resin member composite according to the present invention. [Figure 2] 3 is a diagram showing the shape of an injection-bonded metal-resin test piece used in the examples as an example of an injection-bonded metal-resin test piece. [Figure 3] ;A diagram identifying the joint location based on whether or not the resin remains on the metal side when the joint of an injection-bonded metal-resin test piece is peeled off. [Figure 4] A three-dimensional model of the injection-bonded metal-resin test piece was created, and resin flow analysis data extraction points were set at the joints corresponding to Figure 3. [Figure 5] 3 is a diagram showing the shape of an injection-bonded metal member-resin member composite used in the examples. [Figure 6] A diagram showing the creation of a 3D model of an injection-bonded metal component-resin component composite, with the joint section divided and the resin flow analysis data extraction points set. [Figure 7] ;A plot of predicted joint results comparing calculated viscosity and predicted viscosity at the extraction points segmented from the joint shown in Figure 6 . [Example]

[0028] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples.

[0029] The evaluations used in the examples are shown below.

[0030] <Injection-bonded metal-resin test piece> The shape of the test specimen used in the examples is shown in Figure 2. The test specimen was a 54 mm diameter circle with a plate-shaped metal member (18 mm x 50 mm x 1 mm) inserted in the center. Metallization was performed on the surface where the metal member and resin member came into contact.

[0031] ~Airtightness evaluation~ The molded test piece is clamped in a jig that can apply pressure, and 0.5 MPa of nitrogen is applied. Gas leak detection liquid is applied to the joint between the metal and resin parts of the test piece, and the presence or absence of air bubbles is confirmed. If no air leaks are found, it is determined to be airtight.

[0032] Example An aluminum alloy (A5052) metal part (18 mm x 50 mm x 1 mm) that had been surface-treated using Nano Molding Technology (manufactured by Taiseiplas Co., Ltd.) was inserted into a mold. The cylinder temperature was set to 310°C in an injection molding machine. A polyarylene sulfide composition (manufactured by Tosoh Corporation, product name BGX-545(12)) was poured into the hopper. After pouring into the hopper, the composition was injected into the mold with a filling time of 1 second. After filling, a holding pressure of 60 MPa was applied for a holding time of 10 seconds. After a 30-second cooling period, the mold was removed from the mold, yielding an injection-bonded metal-resin test piece, as shown in Figure 2. The resulting test piece was evaluated for airtightness, and the molded test piece was found to be airtight. The calculated viscosity of the joint was calculated using the test piece after the airtightness evaluation (steps 1 to 4 of the injection-bonded metal-resin test piece in Figure 1).

[0033] The metal and resin parts of an injection-bonded metal-resin test piece were peeled off at the bonding surface. Figure 3 shows a binarized image of the metal bond (18mm x 5mm) after peeling (black: remaining resin, white: no resin remaining). The black part indicates that resin remains on the metal part, and can be determined to be the bond between the resin and metal parts (Step 1).

[0034] A 3D model of the injection-bonded metal-resin test piece was created using SOLIDWORKS (product name) from Dassault Systemes. 360 resin flow data extraction points were set at 0.5 mm intervals at the joint (18 mm x 5 mm) which is the interface between the metal and resin parts in the 3D model (Step 2), as shown in Figure 4.

[0035] A resin flow analysis was performed using Moldex3D (product name) manufactured by CoreTech System. The molding conditions in Step 1 were entered as the molding conditions. After the resin flow analysis was completed, the resin temperature and shear rate when the resin contacted the metal part were extracted as resin flow data at the resin flow data extraction point (Step 3).

[0036] The viscosity of the resin at each extraction point when it contacted the metal was calculated from the resin temperature and shear rate when the resin extracted in Step 3 contacted the metal (Step 4). Note that data on the shear rate dependency of the resin's melt viscosity is required to calculate the viscosity, but since the resin used in this example is not registered in Moldex3D (product name), the shear rate dependency of the melt viscosity was measured separately to obtain the data.

[0037] The viscosity at the joint points on the joint surface of the metal parts observed in step 1 is then compared with the viscosity at the sampled points calculated in step 4, and the relationship between joint and viscosity is derived by comparing the presence or absence of joint and the viscosity at each sampled point. Table 1 shows an excerpt from the comparison of the presence or absence of joint and viscosity. From these results, if the viscosity when the resin part comes into contact with the metal is 290 Pa sec or less, it is determined that joint will occur, and the calculated viscosity when jointability and airtightness are achieved is 290 Pa sec.

[0038] [Table 1]

[0039] Figure 5 shows an injection-bonded metal-resin composite consisting of a metal component made of aluminum alloy (A5052) that had been surface-treated using Nano Molding Technology (manufactured by Taiseiplas Co., Ltd.) and a component made of a polyarylene sulfide composition (manufactured by Tosoh Corporation, product name BGX-545(12)). The molding conditions for the composite were the same as those for the test specimen. Steps 2 to 4 in Figure 1 were carried out using the same procedures as those for the test specimen, and a resin flow analysis of the joint was performed.

[0040] Figure 5 shows the flow data sampling points set on the joint surface between the metal component and the resin component in an injection-bonded metal-resin component composite. 360 sampling points were set at 0.5 mm intervals. The joint was also divided into 360 sections measuring 0.5 mm x 0.5 mm. A sampling point was set at the center of each section (Step 2). Resin flow analysis was then performed at each sampling point, and the resin temperature and shear rate when the resin contacted the metal component were extracted as flow data for the resin (Step 3), and the predicted viscosity of the resin when it contacted the metal component at each sampling point was calculated (Step 4).

[0041] The calculated viscosity of 290 Pa·sec obtained from the injection-bonded metal-resin test piece was used as the standard, and the predicted viscosity of each section was compared to predict the joint. The section where the calculated viscosity was greater than or equal to the predicted viscosity was predicted to be the joint of the injection-bonded metal component-resin component composite. Figure 6 shows the comparison of the predicted viscosity and calculated viscosity of each section in the joint of the injection-bonded metal component-resin component composite. The black sections are sections where the calculated viscosity was greater than or equal to the predicted viscosity, and the white sections are sections where the calculated viscosity was less than the predicted viscosity. The black sections are predicted to be the joint. Furthermore, because the white sections indicate discontinuities, there are no paths through which gas or liquid can pass, and the injection-bonded metal component-resin component composite is predicted to be airtight.

[0042] The results of an actual evaluation of the injection-bonded metal-resin composite showed that it had airtightness and bondability. [Industrial Applicability]

[0043] The method of predicting the joining points of a metal member-resin member composite formed by injection joining in accordance with the present invention from resin flow analysis makes it possible to improve design efficiency and reduce the number of prototypes required compared to conventional design review methods.

Claims

1. A method for predicting the joining points of an injection-bonded metal member-resin member composite, characterized by comparing the calculated viscosity when the resin contacts the metal, obtained from resin flow analysis of an injection-bonded metal-resin test piece having bondability and airtightness, with the predicted viscosity when the resin contacts the metal member, obtained from resin flow analysis of each of the fractions, by dividing the joining point in the injection-bonded metal member-resin member composite into multiple fractions.

2. The method for predicting the joint of an injection-bonded metal member-resin member composite according to claim 1, characterized in that the calculated viscosity is a viscosity calculated through the following steps: Step 1: Evaluating the bondability and airtightness of the injection-bonded metal-resin test piece and identifying the joint location at the joint; Step 2: Creating a three-dimensional model of the injection-bonded metal-resin test piece having bondability and airtightness and setting resin flow analysis data extraction points for the joint; Step 3: Performing resin flow analysis based on the molding conditions of the injection-bonded metal-resin test piece and extracting flow data at each resin flow analysis data extraction point; Step 4: Calculating the viscosity when the resin comes into contact with the metal from the flow analysis data of the joint having bondability and airtightness.

3. 2. A method for predicting the joining points of an injection-bonded metal member-resin member composite according to claim 1, characterized in that the predicted viscosity is a viscosity predicted through the following steps: step 2: creating a three-dimensional model of the injection-bonded metal member-resin member composite, dividing the joint and setting resin flow analysis data extraction points; step 3: performing resin flow analysis based on the molding conditions of the injection-bonded metal-resin test piece and extracting flow data at each resin flow analysis data extraction point; and step 4: predicting each viscosity when the resin comes into contact with the metal member based on the flow analysis data at each extraction point of the divided joint.

4. The method for predicting the joints of an injection-bonded metal member-resin member composite as described in claim 1, further comprising a step of predicting a fraction having an extraction point where the calculated viscosity is greater than or equal to the predicted viscosity as the joint.

5. 2. The method for predicting the joint of an injection-bonded metal member-resin member composite according to claim 1, further comprising a step of predicting airtightness based on discontinuity of the joint at the joint.

6. 2. The method for predicting a joining point of an injection-bonded metal member-resin member composite according to claim 1, wherein the metal member is one or more metal members selected from the group consisting of aluminum members, aluminum alloy members, copper members, copper alloy members, magnesium members, magnesium alloy members, iron members, titanium members, titanium alloy members, and stainless steel members.

7. 2. The method for predicting a joining point of an injection-bonded metal member-resin member composite according to claim 1, wherein the resin member is a polyarylene sulfide member.

8. A method for manufacturing an injection-bonded metal member-resin member composite, characterized in that, when manufacturing an injection-bonded metal member-resin member composite, a mold design is changed based on the method for predicting the joining points of the injection-bonded metal member-resin member composite according to claim 1.

9. A method for manufacturing an injection-bonded metal member-resin member composite, characterized in that, when manufacturing an injection-bonded metal member-resin member composite, molding conditions are changed based on the method for predicting the joining points of the metal member-resin member composite according to claim 1.

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