Press-molded product and method for manufacturing the same

Abstract

To provide a press-formed product in which a main body component is joined to a reinforcement component, which can secure excellent collision resistant performance and rigidity and further is highly manufacturable, and a manufacturing method for the press-formed product.SOLUTION: A press-formed product 1 according to the present invention, which has at least a top plate part 3 and a vertical wall part 5, comprises a main body component 9 constituting the top plate part 3 and the vertical wall part 5, and a reinforcement component 11 arranged across the top plate part 3 and the vertical wall part 5 and joined to the inside or the outside of the main body component 9. An inclined surface part 13 in a planar shape is provided between the top plate part 3 and the vertical wall part 5 across which the reinforcement component 11 is arranged. A joint part 19 is provided at least in the inclined surface part 13, where a width of an inner surface of the inclined surface part 13 is larger than a width of the joint part 19.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a press-formed product having at least a top plate portion and a vertical wall portion, and more particularly to a press-formed product including a main body component constituting the top plate portion and the vertical wall portion, and a reinforcing component disposed across the top plate portion and the vertical wall portion and joined to the inside or outside of the main body component, and a method for manufacturing the press-formed product. [Background technology]

[0002] From the perspective of protecting automobile occupants, improved collision safety is required for vehicle bodies. At the same time, it is also important to reduce the weight of vehicle bodies and improve fuel efficiency in order to reduce carbon dioxide emissions. In order to achieve both collision safety performance and lightweight vehicle bodies, the use of high-strength metallic materials in vehicle body frame components is increasing year by year.

[0003] For example, pillar parts such as the front pillars and center pillars of automobiles are important parts for protecting passengers inside the cabin in the event of a collision, and require strength that can withstand collision loads, so high-tensile steel plates with a tensile strength of 1.5 GPa or higher are used as metal materials. Furthermore, automobile collision safety standards are becoming increasingly strict, and in order to meet these standards, new reinforcing parts are being added to structural parts that require strength, and overlapping structures that partially reinforce parts of the vehicle body are being adopted for pillar parts and the like.

[0004] An example of a conventional press-formed product 39 having an overlapping structure is shown in Fig. 10. The conventional press-formed product 39 having an overlapping structure is composed of a main body part 9 and a reinforcing part 11 joined to the main body part 9, as shown in the schematic diagram of Fig. 10. The main body part 9 has a hat-shaped cross section, and includes a top plate portion 3, a vertical wall portion 5, a flange portion 7, and a ridge portion 41 which is a curved surface portion connecting the top plate portion 3 and the vertical wall portion 5. The reinforcing component 11 is disposed and joined to the inside of the main body component 9 so as to straddle the top plate portion 3 and the vertical wall portion 5. In the conventional press-molded product 39, the joint 19 between the main body part 9 and the reinforcing part 11 is provided on the flat surface of the top plate part 3 or the vertical wall part 5.

[0005] In response to this, Patent Document 1 discloses a "formed member" in which a weld is provided at the ridge line. By providing the weld with the reinforcing member at the ridge line, which is a curved surface with a small radius of curvature, it is possible to obtain a formed member that has axial crushing properties and three-point bending properties, or excellent bending rigidity and torsional rigidity, and is suitable for use as an automobile component. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-87848 Summary of the Invention [Problem to be solved by the invention]

[0007] As described above, providing a joint at the ridgeline can improve the crashworthiness of an automotive part. However, providing a joint at the ridgeline poses the following manufacturing challenges. Below, we will present two examples of manufacturing methods and explain the challenges associated with each method.

[0008] The first manufacturing method is a method in which the main body component 9 and the reinforcing component 11 are press-molded, and the press-molded main body component 9 and reinforcing component 11 are overlapped with each other and the ridge line portion 41 is joined. With this method, there were cases where the joining machine interfered with the main component 9 or the reinforcing component 11, making it impossible to form the joint 19 at the desired position, the ridge 41. Even if the joining machine did not interfere, the ridge 41 had an R-shape with a small radius of curvature, which prevented the electrode from making sufficient contact with the component, resulting in poor joining. Furthermore, there were also cases where the shapes of the joining surfaces of the main component 9 and the reinforcing component 11 did not match easily, resulting in poor contact and insufficient joining.

[0009] The second manufacturing method, as also described in claim 10 of Patent Document 1, is a method in which the main body component 9 and the reinforcing component 11 are joined together in the form of a blank before press molding, and then the two joined blanks are press-molded as a single unit. In this method, joining is performed in the state of a flat blank, so there is no interference from the joining machine, or poor joining caused by poor contact between the joining machine and the parts, or between the parts themselves, as occurs in the first manufacturing method. However, since the area corresponding to the ridge line 41 of the blank is bent after being joined, the joint 19 is subjected to severe bending deformation, which causes cracks 43 to appear on the outer surface of the ridge line 41 (see Figure 11), which is a problem.

[0010] The present invention is devised to solve the above-mentioned problems, and aims to provide a press-molded product in which a main body part and a reinforcing part are joined, which ensures excellent collision resistance and rigidity while preventing cracks from occurring at the joint, and a method for manufacturing such a press-molded product. [Means for solving the problem]

[0011] The present invention prevents interference between a joining machine and a press-molded product, ensures sufficient contact between the electrode and the part, and between the parts, enables good joining without cracks, and makes it possible to manufacture press-molded products with excellent crash resistance and rigidity, and is composed of the following:

[0012] (1) The press-molded product of the present invention has at least a top plate portion and a vertical wall portion, and comprises a main body part constituting the top plate portion and the vertical wall portion, and a reinforcing part arranged across the top plate portion and the vertical wall portion and joined to the inside or outside of the main body part, and has a flat inclined surface portion between the top plate portion and the vertical wall portion on which the reinforcing part is arranged, and a joint portion is provided at least on the inclined surface portion, and the width of the inner surface of the inclined surface portion is wider than the width of the joint portion.

[0013] (2) Furthermore, the press-molded product according to the present invention has at least a top plate portion and a vertical wall portion, and comprises a main body part constituting the top plate portion and the vertical wall portion, and a reinforcing part arranged across the top plate portion and the vertical wall portion and joined to the inside or outside of the main body part, and has a curved inclined surface portion between the top plate portion on which the reinforcing part is arranged and the vertical wall portion, and at least a joint portion is provided on the inclined surface portion, the width of the inner surface of the inclined surface portion is wider than the width of the joint portion, and the cross-sectional radius of curvature of the inner surface of the inclined surface portion is larger than the cross-sectional radius of curvature of the ridge portion between the top plate portion and the inclined surface portion and the cross-sectional radius of curvature of the ridge portion between the inclined surface portion and the vertical wall portion, and is 20 mm or more.

[0014] (3) Furthermore, in the above (1) or (2), the joint is characterized in that it is formed by spot welding, arc welding, laser welding, seam welding, plasma welding, friction stir welding, or ultrasonic welding.

[0015] (4) Furthermore, the method for manufacturing a press-molded product according to the present invention is characterized in that a flat blank serving as a main body part and a flat blank serving as a reinforcing part are stacked together, and at least the portion corresponding to the inclined surface portion is joined to create a joined blank, and the joined blank is press-molded to manufacture a press-molded product described in any one of (1) to (3) above. (5) Furthermore, in the product described in any one of (1) to (3) above, the main body part and the reinforcing part are characterized in that they are press-formed from steel plates having a tensile strength of 980 MPa or more. (6) In addition, in the above (4), the blanks of the main body part and the reinforcing part are made of steel plates having a tensile strength of 980 MPa or more. [Effects of the Invention]

[0016] In the present invention, an inclined surface portion is provided between the top plate portion and the vertical wall portion, and a joint portion is provided on the inclined surface portion, thereby making it possible to manufacture the vehicle while ensuring excellent collision resistance and rigidity and preventing poor joints. That is, in the case of a manufacturing method in which the main body part and the reinforcing part are press-molded and then joined together, sufficient contact between the electrodes and each part, and between each part, is ensured, enabling good joining. Furthermore, in the case of a manufacturing method in which two blanks are joined together and then the joined two blanks are press-formed, bending deformation occurring at the joint can be reduced, thereby preventing cracks. [Brief explanation of the drawings]

[0017] [Figure 1] 1A and 1B are a perspective view and a cross-sectional view, respectively, of a press-formed product according to an embodiment of the present invention; [Figure 2] FIG. 2 is an enlarged view of the portion surrounded by the dashed circle in FIG. 1(b), illustrating the inclined surface portion. [Figure 3] 10A and 10B are diagrams illustrating another aspect of the inclined surface portion. [Figure 4] 10A and 10B are diagrams illustrating another aspect of the joint portion. [Figure 5] 2A to 2C are diagrams illustrating a method for manufacturing the press-formed product of FIG. 1. [Figure 6] 6(a) and 6(b) are a perspective view and a cross-sectional view of another embodiment 1 of the press-molded product. [Figure 7] 7(a) and 7(b) are a perspective view and a cross-sectional view of another embodiment 2 of the press-molded product. [Figure 8] 8(a) and 8(b) are a perspective view and a cross-sectional view of another embodiment 3 of the press-molded product. [Figure 9] 9(a) is a perspective view of a press-formed product according to an embodiment of the present invention, FIG. 9(b) is a cross-sectional view thereof, and FIG. 9(c) is a side view thereof. [Figure 10] 10(a) and 10(b) are a perspective view and a cross-sectional view of a conventional press-formed product, respectively. [Figure 11] 1A and 1B are diagrams illustrating problems with conventional press-formed products. DETAILED DESCRIPTION OF THE INVENTION

[0018] As shown in Figure 1, a press-molded product 1 according to one embodiment of the present invention has an overlapping structure in which a main body part 9 having a hat-shaped cross section and including a top plate part 3, an inclined surface part 13, a vertical wall part 5, and a flange part 7 is joined to a reinforcing part 11 having a shape that fits along the inner surface of the main body part 9. The reinforcing component 11 is a component that reinforces the main body component 9, and is disposed across the top plate portion 3 and the vertical wall portion 5 and joined to the inside of the main body component 9 by spot welding.

[0019] The press-formed product 1 of this embodiment has a flat inclined surface portion 13 between the top plate portion 3 and the vertical wall portion 5. The inclined surface portion 13, which is a feature of the present invention, will be described in detail below with reference to FIG. FIG. 2 is an enlarged view of the area enclosed by the dashed circle in FIG. 1(b). As shown in FIG. 2, the inclined surface portion 13 of the main body component 9 is continuous with the top plate portion 3 via a ridge portion 15 and is also continuous with the vertical wall portion 5 via a ridge portion 17 . The ridge line portion 15 and the ridge line portion 17 are curved surface portions that connect the top plate portion 3 or the vertical wall portion 5 to the inclined surface portion 13. Therefore, the reinforcing part 11 , which has a shape that fits along the main body part 9 , also has a shape that corresponds to the top plate part 3 , the ridge part 15 , the inclined surface part 13 , the ridge part 17 and the vertical wall part 5 . The width W of the inclined surface portion 13 is wider than the width of the joint portion 19 so that the joint portion 19 described later fits within the inclined surface portion 13 without protruding onto the ridge line portion 15 or the ridge line portion 17 .

[0020] The reinforcing component 11 is joined to the main body component 9 by a joint 19 provided on the inclined surface portion 13. The joint 19 is formed by spot welding, for example, and is provided in the extending direction of the inclined surface portion 13, as shown in FIG. 1(a). Similar joints 19 are also provided on the top plate portion 3 and the vertical wall portion 5. It should be noted that providing the joints 19 on the top plate portion 3 and the vertical wall portion 5 is not essential in the present invention, and the joints 19 may be provided only on the inclined surface portion 13 .

[0021] Furthermore, the inclined surface portion of the present invention is not limited to a flat surface as shown in FIG. 2, but may have a cross section with a gently curved shape as shown in FIG. In this case, the width W of the inclined surface portion 13 is also wider than the joint portion 19, and the joint portion 19 is arranged to fit within the inclined surface portion 13 without protruding onto the ridge line portion 15 or the ridge line portion 17. When the inclined surface portion 13 has a curved shape, the width length differs between the inner surface and the outer surface of the inclined surface portion 13, and therefore the portion with the shortest width length, i.e., the width on the inner surface of the inclined surface portion 13, corresponds to the width W in this description.

[0022] The cross-sectional curvature radius of the curved inclined surface portion 13 on the inner side of the bend is R S , the cross-sectional curvature radii of the ridge line portion 15 and the ridge line portion 17 on the inner side of the bend are R1 and R2, respectively, R S The relationship between R1 and R2 is as follows: R S >>R1, R S >>R2···(1) Generally, the cross-sectional radius of curvature of the ridge line portion 15 or the ridge line portion 17 is about 3 to 6 mm, and does not exceed 10 mm at the maximum. However, in the present invention, the cross-sectional radius of curvature R of the inclined surface portion S is larger than the cross-sectional curvature radius R1 and the cross-sectional curvature radius R2, and should be 20 mm or more. S The reason why the distance is set to 20 mm or more will be specifically explained in the examples below.

[0023] Furthermore, the joint 19 is not limited to being provided intermittently by spot welding as shown in FIG. 1(a), but may also be provided continuously in the extending direction of the inclined surface portion 13 by arc welding, laser welding, seam welding, plasma welding, friction stir welding, ultrasonic welding, etc. as shown in FIG. 4(a). The joint 19 may be formed at the interface between the main body component 9 and the reinforcing component 11 as shown in Figure 1(b), or may be formed from the outer surface of the main body component 9 to the inner surface of the reinforcing component 11 as shown in Figure 4(b).

[0024] The press-formed product 1 configured as described above has a flat or gently curved inclined surface portion 13 between the top plate portion 3 and the vertical wall portion 5, thereby solving the manufacturing problem that has conventionally arisen when joining ridge portions with a small radius of curvature between the top plate portion 3 and the vertical wall portion 5. This point will be specifically described below in the description of the manufacturing method of the press-formed product 1.

[0025] <Method of manufacturing press-molded products> An example of a method for manufacturing the press-formed product 1 of this embodiment will be described with reference to FIG. First, as shown in FIG. 5(a), a flat blank 21 to be formed into the main body part 9 and a flat blank 23 to be formed into the reinforcing part 11 are set in an overlapping state.

[0026] Next, as shown in Fig. 5(b), at least the portions 20 (portions 20 corresponding to the inclined surface portions) of the blanks 21 and 23 corresponding to the inclined surface portions 13 are joined to produce a joined blank 25. Note that, if necessary, portions corresponding to the top plate portion 3 and the vertical wall portion 5 are also joined. As described above, the joining method in this case may be, for example, spot welding, seam welding, laser welding, plasma welding, friction stir welding, ultrasonic welding, etc. Note that Fig. 5(b) illustrates an example of spot welding using an electrode 27.

[0027] In this way, by first joining the main body component 9 and the reinforcing component 11 in the form of a flat blank, it is possible to ensure good contact between the electrode 27 and each component, and poor joining is less likely to occur, compared to when each component is press-formed and then joined. Furthermore, gaps are less likely to occur between the main body component 9 and the reinforcing component 11 after press molding, and the contact state between the components is also good.

[0028] After producing the joined blank 25, as shown in Figure 5(c), the joined blank 25 is press-formed using a mold (die 29, punch 31) having a shape corresponding to the target shape, to obtain the press-formed product 1 shown in Figure 5(d).

[0029] In the case of a press-formed product in which a ridge portion 41 with a small cross-sectional radius of curvature is joined as described in the conventional Patent Document 1, large bending deformation occurs at the joint 19 during press forming, and a crack 43 occurs on the outside of the bend (see Figure 11). In this regard, the press-molded product 1 of this embodiment has a flat or gently curved inclined surface portion 13 at the portion corresponding to the conventional ridge portion 41, and the inclined surface portion 13 is joined, so that no large bending deformation occurs at the joint portion 19 and cracking can be suppressed. This makes it possible to manufacture a press-molded product 1 in which the main body part 9 and the reinforcing part 11 are stacked together while preventing cracks at the joint, and to manufacture a press-molded product 1 with excellent collision resistance and rigidity.

[0030] 2 have a small cross-sectional radius of curvature, cracks are likely to occur if the joint 19 extends to these areas. Therefore, in FIG. 5(b), it is necessary to set the width W of the inclined surface portion equivalent portion 20 wider than the width of the joint 19, and to form the joint 19 within the inclined surface portion equivalent portion 20.

[0031] Furthermore, the press-forming of the press-formed product 1 is not limited to one process, and the press-formed product 1 having a target shape may be obtained through a plurality of processes. The press forming of the joined blank 25 may be a bending forming as shown in FIG. 5(c) or a drawing forming using a blank holder.

[0032] The above is a manufacturing method in which the main body part 9 and the reinforcing part 11 are joined in the blank state before press molding, but the press-molded product 1 of this embodiment can also be applied to a manufacturing method in which the main body part 9 and the reinforcing part 11 are press-molded separately and then joined. For example, in the case of a conventional press-formed product that does not have the inclined surface portion 13, the ridge portion 41, which is curved with a small radius of curvature, is joined, so that sufficient contact between the electrode 27 and the component or between the components cannot be ensured, which causes poor joining. However, the press-formed product 1 of the present embodiment joins the components together using the inclined surface portion 13, which is flat or has a gentle curve, so that sufficient contact between the electrode 27 and the component or between the components can be ensured, and poor joining is less likely to occur.

[0033] Furthermore, the press-formed product targeted by the present invention is not limited to one in which the main body component 9 has a hat-shaped cross section, but may have a U-shaped cross section, as in the press-formed product 33 shown in FIG. 7, a press-molded product 35 may be provided with a reinforcing part 11 having an L-shaped cross section and arranged across the top panel 3 and one of the vertical wall parts 5.

[0034] Furthermore, the press-molded product covered by the present invention is not limited to one in which the reinforcing part 11 is arranged inside the main body part 9, but may also be one in which the reinforcing part 11 is arranged outside the main body part 9, as in the press-molded product 37 shown in Figure 8. In either case, the interior angle between the top plate portion 3 and the vertical wall portion 5 should be 90° or more to facilitate demolding after press molding. [Example]

[0035] In order to confirm the effects of the present invention, specific press forming was carried out, which will be described below. The target shape in this example will be described with reference to FIG. 9 shows an example of a target shape in an example of the invention or a comparative example, which will be described later. The press-formed product 1 shown in FIG. 9 is the same as that in FIG. 1, and is therefore denoted by the same reference numerals as in FIG. As shown in Figure 9, in this example, press molding was performed with a target shape of a press-formed product 1 formed by joining a main body part 9 having a hat-shaped cross section and a reinforcing part 11 having a U-shaped cross section arranged inside the main body part 9.

[0036] As an example, the press-formed product 1, which is the target shape, has a length of 240 mm, a height of 75 mm, and a width of 130 mm, and the interior angle between the top plate portion 3 and the vertical wall portion 5 is 100°, as shown in Fig. 9(c). The joining was performed by spot welding, with the width of the joint (nugget diameter) set to 5 mm, and the top plate portion 3, vertical wall portion 5, and inclined surface portion 13 joined at intervals of 40 mm in the longitudinal direction of the press-formed product. The blank used for the main body part 9 was a 1180 MPa steel plate with a thickness of 1.4 mm, and the blank used for the reinforcing part 11 was a 1470 MPa steel plate with a thickness of 1.4 mm.

[0037] 10 and 11, a press-formed product 39 was also press-formed in which an R-shaped ridge line 41 connecting the top plate 3 and the vertical wall 5, the top plate 3, and the vertical wall 5 were spot-welded. The cross-sectional curvature radius of the ridge line 41 in the conventional example (cross-sectional curvature radius on the inside of the bend) was 6 mm.

[0038] In the present invention example and the comparative example, the cross-sectional curvature radius R1 of the ridge line portion 15 and the cross-sectional curvature radius R2 of the ridge line portion 17 were each set to 6 mm, the same as the ridge line portion 41 of the conventional example. In the present invention example and the comparative example, press forming was also performed when the inclined surface portion 13 was made flat or curved, and the cross-sectional curvature radius R S Also, the width W of the inclined surface portion 13 was changed.

[0039] The press forming of the conventional example, comparative example, and example of the present invention was carried out using the manufacturing method shown in FIG. Specifically, blank 21 and blank 23 were overlapped and spot-welded at the portions corresponding to top plate portion 3 and vertical wall portion 5, and also spot-welded at the portion corresponding to inclined surface portion 13 in the present invention example and comparative example, and at the portion corresponding to ridge portion 41 in the conventional example, to produce joined blank 25. Thereafter, joined blank 25 was press-molded in a mold corresponding to the target shape, to obtain the desired press-molded product. Then, the joint 19 between the main body part 9 and the reinforcing part 11 after press molding, particularly the joint 19 at the part connecting the top plate part 3 and the vertical wall part 5 (the inclined surface part 13 or the ridge part 41) was visually inspected for cracks. The results are shown in Table 1.

[0040] [Table 1]

[0041] Conventional example No. 1 has only an R-shaped ridge portion 41 between the top plate portion 3 and the vertical wall portion 5 (see FIG. 11). When the ridge portion 41 with a cross-sectional curvature radius of 6 mm was joined, cracks occurred at the joint 19 of the ridge portion 41 after press forming.

[0042] Comparative examples No. 2 and No. 3 have a curved inclined surface portion 13 between the top plate portion 3 and the vertical wall portion 5 (see Figure 3), and the width W of the inclined surface portion 13 is 3 mm, which is narrower than the width of the joint (5 mm). In addition, No. 4, which is a comparative example, has a flat inclined surface portion 13 between the top plate portion 3 and the vertical wall portion 5 (see Figure 2), and like Nos. 2 and 3, the width W of the inclined surface portion 13 is narrower than the width of the joint. In Nos. 2 to 4, joint 19 protruded from inclined surface 13 and extended to ridgeline 15 or ridgeline 17, which had a cross-sectional curvature radius of 6 mm, so cracks occurred in joint 19 regardless of the shape of inclined surface 13.

[0043] In addition, in No. 5, which is a comparative example, the width W of the inclined surface portion 13 is set to 7 mm, which is wider than the width (5 mm) of the joint portion 19, but the cross-sectional curvature radius R of the inclined surface portion 13 is S In this case, the radius of curvature R of the inclined surface portion 13 is 10 mm, which is smaller than the 20 mm of the present invention. S Because the stress was small, a crack occurred at the joint 19.

[0044] In contrast, in Nos. 6 and 7, which are examples of the present invention, the width W of the inclined surface portion 13 is wider than the width of the joint portion 19, and the cross-sectional curvature radius R of the inclined surface portion 13 is S The thickness is increased to 20 mm or more. In addition, No. 8, an example of the present invention, has a flat inclined surface portion 13 between the top plate portion 3 and the vertical wall portion 5 (see Figure 2), and the width W of the inclined surface portion 13 is wider than the width of the joint portion 19. In all of the examples Nos. 6 to 8 of the present invention, no cracks occurred in the bonded portion 19.

[0045] As described above, in this embodiment, by providing a flat inclined surface portion 13 or a curved inclined surface portion 13 with a cross-sectional curvature radius of 20 mm or more, and by providing a joint portion 19 so that it fits within the inclined surface portion 13, it was confirmed that cracking of the joint portion 19 between the main body component 9 and the reinforcing component 11 can be prevented. [Explanation of symbols]

[0046] 1 Press-molded products 3 Top plate 5 Vertical wall section 7 Flange 9 Main body parts 11 Reinforcement parts 13 Slope section 15 Ridgeline 17 Ridge 19 Joint 20 Part corresponding to the inclined surface part 21 Blank 23 Blank 25 Bonded Blanks 27 electrodes 29 Die 31 Punch 33 Press-molded products (other aspects 1) 35 Press-molded products (other aspects 2) 37 Press-molded products (other aspects 3) 39 Press-molded product (conventional example) 41 Ridge 43 Crack

Claims

1. A press-molded product having a hat cross-sectional shape having at least a top plate portion, a vertical wall portion, and a flange portion, or a U-shaped cross-sectional shape having at least a top plate portion and a vertical wall portion, comprising: a main body part constituting the top plate portion and the vertical wall portion; and a reinforcing part having a shape that conforms to the main body part, arranged across the top plate portion and the vertical wall portion and joined to the inside or outside of the main body part; a planar inclined surface portion that is continuous with the top plate portion and the vertical wall portion via two ridge portions between the top plate portion and the vertical wall portion on which the reinforcing component is arranged, a ridge line portion of the reinforcing component overlaps with a ridge line portion of the main body component, and a joint portion is provided at least on the inclined surface portion, A press-formed product, characterized in that the width of the inner surface of the inclined surface portion is wider than the width of the joint portion.

2. A press-molded product having a hat cross-sectional shape having at least a top plate portion, a vertical wall portion, and a flange portion, or a U-shaped cross-sectional shape having at least a top plate portion and a vertical wall portion, comprising: a main body part constituting the top plate portion and the vertical wall portion; and a reinforcing part having a shape that conforms to the main body part, arranged across the top plate portion and the vertical wall portion and joined to the inside or outside of the main body part; a curved inclined surface portion that is continuous with the top plate portion and the vertical wall portion via two ridge portions between the top plate portion and the vertical wall portion on which the reinforcing component is arranged, a ridge line portion of the reinforcing component overlaps with a ridge line portion of the main body component, and a joint portion is provided at least on the inclined surface portion, The width of the inner surface of the inclined surface portion is wider than the width of the joint portion, A press-molded product characterized in that the cross-sectional radius of curvature of the inner surface of the inclined surface portion is larger than the cross-sectional radius of curvature of the ridge portion between the top plate portion and the inclined surface portion and the cross-sectional radius of curvature of the ridge portion between the inclined surface portion and the vertical wall portion, and is 20 mm or more.

3. 3. The press-formed product according to claim 1, wherein the joint is formed by spot welding, arc welding, laser welding, seam welding, plasma welding, friction stir welding, or ultrasonic welding.

4. a flat blank serving as a main body part and a flat blank serving as a reinforcing part are overlapped and joined at least at a portion corresponding to the inclined surface part to form a joined blank; A method for producing a press-formed product, comprising press-forming the joined blank to produce the press-formed product according to claim 1 or 2.

5. 3. The press-formed product according to claim 1, wherein the main body part and the reinforcing part are formed by press-forming a steel plate having a tensile strength of 980 MPa or more.

6. 4. The press-formed product according to claim 3, wherein the main body part and the reinforcing part are formed by press-forming a steel plate having a tensile strength of 980 MPa or more.

7. 5. The method for manufacturing a press-formed product according to claim 4, wherein the blanks for the main body part and the reinforcing part are made of steel plates having a tensile strength of 980 MPa or more.

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