JPS61279548A - Laminated steel plate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] <Industrial Application Field> The disclosed technology belongs to the technical field of laminated steel plates used as panel materials to reduce the weight of automobiles and the like.

Summary of the gist> This invention relates to a laminated steel plate in which a steel plate and a lightweight plate are polymerized and integrally joined via an adhesive polymer material such as modified polypropylene or deformed nylon. In particular, the invention relates to a laminated steel plate in which the lightweight plate material integrally joined to the steel plate material is a metal plate material with good workability such as an aluminum plate.

<Conventional technology> In recent years, there has been an increasing demand in the automobile industry for vehicles to be more fuel efficient, and in order to meet this demand, various innovations and improvements have been made to improve the efficiency of engines and transmissions, make vehicles lighter, and reduce running resistance. is being done.

One of the ways to reduce the weight of vehicles is to use lightweight materials for vehicle components.
This lightweight material is currently attracting attention not only in the automobile industry but also in other industries.

Steel plates are used in many products such as automobiles, but since the steel plates are heavy, they have been used as an alternative for the above-mentioned material weight reduction.

Conventionally, lightweight materials that can replace the above-mentioned steel plates include:
Aluminum plates or laminated steel plates made of two steel plates with a resin plate interposed between them have been used.

(Problems to be Solved by the Invention) However, the embodiment using the aluminum plate described above cannot be applied to parts that require advanced press forming due to the structural properties of aluminum material, which is unsuitable for plastic deformation. In addition, due to the nature of aluminum material, which requires different coating conditions than steel plate, in the case of a product that contains steel and aluminum materials in the same painted area, the steel and aluminum parts may be painted differently. The process is considered essential,
This had the disadvantage of reducing production efficiency.

On the other hand, in an embodiment using a laminated steel plate in which a resin plate is interposed between the two steel plates mentioned above, as shown in FIG. As the stress decreases, the bending stress of the steel plate 2 increases accordingly, so during press forming that requires high forming, too much stress is placed on the steel plate 2, which may lead to damage or breakage of the material during press forming. There was a problem.

In addition, such laminated steel plates cannot be spot welded under normal conditions because the resin plate 1 is interposed between the steel plates 2 and 2 and they do not have electrical conductivity. Therefore, an auxiliary electrode is installed when joining the materials. There is also an inconvenience in that spot welding must be performed or other complicated joining means such as riveting must be employed.

The purpose of this invention is to solve the problems of laminated steel plates based on the above-mentioned prior art, and to make it possible to reduce the weight of the material, maintain good workability, and further increase the versatility of lightweight materials. The objective is to provide an excellent laminated steel structure that is useful in the field of lightweight material utilization in industry.

In order to solve the above-mentioned problems, the structure of the present invention, which is based on the above-mentioned object and the gist of the above-mentioned claims, is to solve the above-mentioned problems by interposing an adhesive at once and using a steel plate. This technology allows the material to be integrated with a lightweight, well-workable metal sheet to maintain sufficient rigidity while being lightweight, and can also be used for various types of processing. The measures taken were as follows.

<Embodiment - Configuration> Next, one embodiment of the present invention will be described below based on FIG. 1.

Incidentally, the same reference numerals are given to the same parts as those shown in FIG. 4 used in the explanation of the prior art described above.

3 is a laminated steel plate of the present invention, and the laminated III plate 3 is formed by interposing an aluminum plate 4 as a core material on one of a pair of steel plates 2.2 as a skin plate to form a laminate structure. An adhesive polymeric material 5 such as polyamide, polyester, modified polyolefin, Evoquin, phenol, etc. is interposed between the upper and lower surfaces of 4 and the 2 surfaces of the steel plate and bonded to each other.

The steel plate 2.2 has a thickness of o, i to 0.8 ma+, the aluminum plate 4 has a thickness of 0.1 to 2 InIIl, and the polymer material 5 is mainly adhesive modified polypropylene, Modified nylon etc. is 0. It is applied and used up to 11m.

Further, the characteristics of the steel plate 2, aluminum plate 4, and polymer material 5 (polypropylene) are shown in the table below.

Table: Material properties <Example - Effect> In the above configuration, with reference to the above table and FIGS. 2 to 7,
The function of such a laminated steel plate 3 will be explained.

Regarding weight, as shown in the table above, the specific gravity of aluminum is about 1/3 of that of steel, so the laminated steel plate 3 can be made by changing the thickness of the steel plate 2 and the aluminum plate 4 as appropriate. , 4-74% compared to a single steel plate with equal rigidity
The weight can be reduced.

In terms of rigidity, as shown in the table above, the elastic modulus of aluminum is about 40% that of steel, and about 8% that of polypropylene.
4%, when a bending moment is applied to the laminated steel plate 3, the laminated steel plate exhibits a bending stress distribution as shown by the horizontal arrow in Fig. 2, and as can be seen by comparing it with Fig. 4. Compared to a conventional laminated steel plate in which the resin 1 is interposed between the steel plates 2 and 2, the stress shared by the steel plate 2 is reduced.

As a result, in the laminated steel plate 3, the forming area up to the skin breakage when bending deformation is increased compared to conventional laminated steel plates, and the press formability is further improved.

Furthermore, in terms of bondability to other objects to be bonded, in this laminated steel plate 3, the thickness of the adhesive polymer material 5 interposed between the steel plate 2 and the aluminum plate 4 is 0.611 mm or less, and the aluminum plate Since 4 has electrical conductivity, spot welding similar to that of a single steel plate is possible by appropriately adjusting the welding time, welding current value, etc.

5 to 7 show each of a single steel plate, such a laminated steel plate 31, and a conventional laminated steel plate interposed with resin being connected to the spot welding machine 6, and the double-headed arrow indicates the energization. The objects to be joined are omitted for illustration convenience.

Regarding paintability, since the skin material is a rigid plate, it can be painted under the same painting conditions as a single steel plate.

Other Examples〉 The actual results of this invention are as follows: Of course, the aspect is not limited to the above-mentioned embodiment. For example, the bonding structure between the steel plate 2 and a metal material with good workability such as aluminum may not be a laminate structure but a two-layer structure as shown in FIG. Alternatively, in the case of a laminate structure, the thickness of the upper and lower steel plates 2.2 may be different as shown in FIG. 9, and the metal material with good workability may be other than aluminum. A number of similar embodiments can be adopted.

<Effects of the Invention> As described above, according to the present invention, the excellent effects of basically making it possible to reduce the weight of the material, improving workability, and further increasing the versatility of the light chain material are achieved.

In other words, the adhesive is interposed in one piece, and the steel plate material and the lightweight, well-workable metal plate material are integrated together, making it possible to maintain sufficient rigidity in addition to being lightweight. Moreover, the excellent effect of enabling adaptation to various processing such as painting is achieved.

[Brief explanation of the drawing]

Fig. 1.2.5.8.9 is a detailed sectional view of the present invention, and Fig. 3.4.6.7 is a sectional view of the conventional embodiment. 5...Adhesive, 2...Steel plate material, 4...Lightweight plate material, 3...Laminated steel plate Applicant Toyota Motor Corporation Figure 1 Figure 2 Figure 4

Claims (1)

[Claims] 1. A laminated steel plate in which a steel plate material and a lightweight plate material are integrated together by interposing an adhesive, wherein the lightweight plate material is a metal material with good workability.