JPH05146881A - Method and device for manufacturing clad material - Google Patents

Abstract

PURPOSE:To manufacture the clad material capable of sufficiently securing joining strength and having little ruggedness on the joining face. CONSTITUTION:A clad material rolling device is provided with rolling mills 1, roll benders 5 arranged on a path to feed base metal 3 to these rolling mills 1 and roll benders 9 arranged on a path to feed covering material 7 to the rolling mills 1, applies tensile bending on the base metal 3 and the covering material 7 and then, performs rolling. The strength of tensile bending is rugulated to the strength to give elongation of >=0.1%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for producing a clad material for joining a base material and a covering material by rolling.

[0002]

2. Description of the Related Art Conventionally, in a method of manufacturing a clad material by cold pressure welding, an oxide film on a bonding surface is removed, so
As shown in (1), the structure in which the surface of the base material 101 is ground by the wire brush 103 and then supplied to the rolling mill 107 together with the coating material 105 has been adopted.

[0003]

However, there is a problem in that irregularities on the surface of the base material, which are generated as a result of grinding with the wire brush, appear as they are at the bonding interface of the clad material. Therefore, when a lead frame or the like is manufactured by etching the clad material, this uneven surface is exposed, and there is a problem that a flat surface cannot be exposed. Further, due to the unevenness, there is a problem that lead wire bonding failure occurs in a thin portion of the covering material.

As shown by ●, ▲, and ■ in FIG. 2, such irregularities do not make much difference even if the diameter of the wire brush is reduced, and can be reduced to at most about 5 μm by further rolling after the cladding. There wasn't. On the other hand, if the degree of brush grinding is weakened, the occurrence of such irregularities can be prevented, but this causes a problem that the new surface is not sufficiently formed and good bonding cannot be performed.

Therefore, the present invention has been completed with the object of providing a novel clad material manufacturing method and manufacturing apparatus which employ a newly-formed surface forming method capable of ensuring a sufficient bonding strength and not causing irregularities on the bonding surface.

[0006]

In order to achieve the above object, the present invention provides a method for producing a clad material in which a base material and a covering material are joined by rolling so that the base material and / or the covering material is pulled. It is characterized in that the rolling is performed after the bending is applied.

If tensile bending is applied before rolling, a crack is generated in the oxide film on the surface of the base material and / or the covering material, and a new surface is formed. As a result, the clad rolling can be performed well. At this time, the oxide film can be surely ruptured if the tensile bending is performed under the condition that the tensile bending is such that elongation of 0.1% or more is imparted.

Since the bending stress is zero at the neutral axis and becomes maximum on the surface, only the tensile stress due to the axial force acts near the neutral axis, but the bending stress is added to the tensile stress due to the axial force near the surface. The stress acts in a curved shape.
Therefore, by adopting tensile bending, it is possible to apply a large stress to the oxide film on the surface without applying a large stress to the base material, etc., and it is easier to rupture than simply adding tension. It will be easier.

In such a method, in a clad material manufacturing apparatus for joining a base material and a coating material in a rolling mill, a roll bender for passing the base material and / or the coating material before rolling is provided on the inlet side of the rolling mill. If the clad material manufacturing apparatus characterized by the arrangement is used, it can be easily carried out by utilizing the backward tension of the rolling mill.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments will be described with reference to the drawings in order to further clarify the present invention. As shown in FIG. 1, the clad material manufacturing apparatus of the embodiment covers a rolling mill 1, a roll bender 5 arranged on a route for feeding the base metal 3 to the rolling mill 1, and a rolling mill 1. The roll bender 9 is provided on the path for feeding the material 7.

In this apparatus, the base material 1 has a plate thickness of 0.
A 4 mm Fe-42% Ni steel strip was used, and an Al strip having a thickness of 0.05 mm was used as the covering material 7, the line speed in the rolling mill 1 was 10 m / min, and the rolling reduction was 40.
%, The roll benders 5 and 9 having a roll diameter of 20 mmφ are used, and the rolls are arranged so that the tensile bending conditions shown in Table 1 below are satisfied from the relationship with the line speed. went.

[0012]

[Table 1]

The tension is the backward tension of the rolling mill, and the elongation is the amount of elongation remaining in the base material and the covering material after tensile bending. On the other hand, in the conventional apparatus shown in FIG. 4, the base material, the covering material, and the rolling conditions are set to be the same as those in the apparatus of the above-described embodiment, and the wire diameter of the wire brush is set to 0.
Rolling was performed under three different conditions of 1 mmφ, 0.2 mmφ, and 0.3 mmφ.

The clad material manufactured by using the apparatus of the embodiment and the apparatus of the conventional example in this way is rolled in the state as it is, and further after the clad is rolled at respective reduction ratios of 20%, 40%, 60% and 80%. A state sample was obtained. FIG. 2 shows the result of examining the concavo-convex state of the joint surface after etching each of these samples and removing the coating material.

As shown in the figure, when the conventional apparatus is used, the maximum roughness Rmax is about 1 immediately after the cladding.
The maximum roughness Rmax could be reduced to only about 5 μm, although it was considerably large at 0 μm and was slightly reduced by rolling thereafter. On the other hand, in the case of using the apparatus of the embodiment, the maximum roughness Rmax is maintained even immediately after the cladding.
Was as small as 2.0 μm, and could be reduced to 1 μm or less by rolling thereafter.

On the other hand, FIG. 3 shows the results of the joint strength obtained from the load required for peeling the covering material from the clad material manufactured in the example and the clad material manufactured in the conventional example. As shown in the figure, the clad materials manufactured according to the examples had rather higher bonding strength than the clad materials manufactured according to the conventional example.

As described above, the clad material produced by the apparatus of this embodiment has extremely small irregularities on the joint surface, and the joint strength is improved rather than the conventional example. As a result, the base material surface after the coating material is removed by etching is flat, and no bonding failure due to unevenness occurs when the lead wire is bonded.

As in the embodiment, Fe- is used as the base material 1.
42% Ni steel strip is used and Al is used as the covering material 7.
As the rolling conditions when using the strip plate, the line speed is set to 80 m / min or less, the rolling reduction is set to 30% or more, and the roll diameter and the arrangement of the roll bender are set so as to satisfy the tensile bending conditions shown in Table 2 below. Should be adjusted.

[0019]

[Table 2]

In this case, the roll diameter is preferably 100 mmφ or less. Although the embodiments of the present invention have been described above, it is needless to say that the present invention is not limited to these embodiments and can be implemented in various modes without departing from the scope of the invention.

For example, the roll bender may be arranged only on the side of the base material, or the light grinding with the wire brush may be performed in combination with the tension bending by the roll bender. Further, the method of the present invention is not limited to the device for applying the tensile bending by the roll bender, and the method of the present invention may be realized by the device configuration for applying the tensile bending by another method.

[0022]

As described above, according to the method for manufacturing a clad material of the present invention, it is possible to manufacture a clad material which can secure a sufficient bonding strength and has small irregularities on the bonding surface. Further, according to the clad material manufacturing apparatus of the present invention, such a favorable manufacturing method can be easily implemented.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a clad material manufacturing apparatus according to an embodiment.

FIG. 2 is a graph comparing the roughness of the joint surface of the clad materials manufactured by the method of the example and the conventional example.

FIG. 3 is a graph comparing the bonding strength of the clad materials manufactured by the method of the example and the conventional example.

FIG. 4 is a configuration diagram of a conventional clad material manufacturing apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rolling mill, 3 ... Base material, 5 ... Roll bender, 7 ... Coating material, 9 ... Roll bender.

Claims (3)

[Claims] 1. A method for producing a clad material for joining a base material and a covering material by rolling, wherein the rolling is performed after tensile bending is applied to the base material and / or the covering material. Production method. 2. The method for producing a clad material according to claim 1, wherein the tensile bending is conditioned on the tensile bending having a strength that gives elongation of 0.1% or more. 3. A clad material manufacturing apparatus for joining a base material and a coating material with a rolling mill, wherein a roll bender for passing the base material and / or the coating material before rolling is arranged on the entrance side of the rolling mill. An apparatus for manufacturing a clad material, which is characterized in that