JPH0747228B2 - Material heating method during the production of cladding materials - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for efficiently and stably heating a raw material for producing a clad material by rolling and pressure bonding different metal strip raw materials.

<Background Art> Clad materials that combine different types of metals with different properties and have the advantages of each other have become widely used in various fields in recent years, but the hot rolling pressure welding method has good manufacturing efficiency. In the case of producing a clad material by rolling, generally, as shown in FIG. 4, the dissimilar metal strip materials 1 and 1'are rewound and superposed, and then heated by passing through a heating furnace 2, which is then rolled. And 3 '. The reference numeral 4 in the drawings is a take-up reel.

However, it is pointed out that this method requires a considerably long heating furnace to keep the material temperature on the inlet side of the rolling mill constant, and the material strips are heated to different temperatures. If necessary, No. 5
As shown in the figure, a separate heating furnace 2'is required, and the space occupied by the heating furnace such as the height space is further increased. Moreover, when the strip is heated by such a long heating furnace, the strip in the heating furnace is affected by the "operating limitation" and "yield reduction" due to the meandering of the strip and the effect of the applied tension. I could not overlook the problems such as "width shrinkage" and "breakage".

In addition, in order to improve the bonding of the clad material that has been crimped by rolling, the crimping material (also referred to here as “material”) that has come out of the rolling mill is again introduced into the annealing furnace and heated. However, in this case, another heating furnace was needed, and the space problem had to be exacerbated.

<Means for Solving Problems> In order to solve the above-mentioned problems found in the conventional clad material manufacturing means for rolling and crimping a strip material, the present invention carries out experiments and studies from various viewpoints. It was completed through repeated research by the inventors of the present invention, such as "When manufacturing a clad material by rolling and pressure bonding two or more kinds of metal strip materials, the material (not only the strip material but Improving the bonding after coming in (including the pressure-bonding material before heating) is performed by contacting the heating roll with heating and adjusting the heating temperature by adjusting the contact length between the heating roll and the material. It enables efficient and sufficient heating under the smallest space for heating equipment, and eliminates the possibility of trouble such as strip meandering, necking or breakage during heating. Those characterized by a more elevated "point to stabilize the clad material manufacturing operations.

Here, the type of the "metal strip material" is not particularly limited, and may be carbon steel, stainless steel, aluminum or aluminum alloy, titanium or titanium alloy, or the like. Further, as the "heating roll" to be used, it is preferable to use a roll (for example, a jacket roller: trade name) in which an induction coil is incorporated inside to generate heat by itself, or a type of heat generating roll that is heated by a burner from inside .

FIG. 1 is a schematic view schematically showing an example of heating a clad material according to the present invention.

For example, a case of manufacturing a three-layer clad material using the aluminum strip 5 as a base material and other metal strips 6 and 6'as a joining material will be described. In FIG. 1, the aluminum strip 5 is a rolling roll 3, 3 '. Before being supplied to the substrate, it is wrapped around a heating roll 7 and heated by contact with the solid. Further, the other metal strip 6 is a material which is not heated and rolled and pressure-bonded, and is unwound and superposed on the aluminum strip 5 as it is and supplied to the rolling rolls 3 and 3 '. Then, like the aluminum strip 5, the other metal strip 6'is heated by the heating roll 7'to the same temperature as or different from that of the aluminum strip, and then stacked on the aluminum strip 5 and supplied to the rolling rolls 3, 3 '. It

As is clear from FIG. 1, in the method of the present invention, the space required is much smaller than that in the conventional "method of passing through a heating furnace" for heating the material strip by means of solid contact heating using a heating roll. It will be appreciated that it is very small and therefore it is very easy to heat two or more strips of material to different temperatures. Next, regarding the heating temperature of the strip, it may be possible to adjust it by the current flowing through the roll, but this method is difficult to adjust because the responsiveness during the temperature rise and temperature decrease of the roll, especially during temperature decrease, is poor. It turned out by experiment. Therefore, the present invention is
As shown by the outline arrows in FIGS. 1 and 2,
By adjusting the position of the heating roll 7 to adjust the contact length between the heating roll and the material strip, the amount of heat transferred to the material strip can be freely adjusted (in this case, the temperature of the heating roll can also be adjusted. If done at the same time, the control temperature range will become wider and it will be possible to cope with the desired heating temperature of various clad materials. Therefore, there is an advantage that the heating temperature of the material strip can be adjusted very easily.

By the way, when solid contact heating of an aluminum strip (plate thickness 2 mm) running at a line speed of 1.0 m / min with a 400 mmφ jacket roller (trade name) was performed, the temperature of the jacket roller (trade name) was kept constant. Then, the contact time between them, the winding angle, and the strip temperature have the following relationship.

Further, since the material strip is wound around the heating roll at the time of heating, meandering of the material strip is effectively prevented by the frictional force between them and the material strip is constrained in the width direction by the frictional force. Therefore, it is possible to prevent the phenomenon in which the material heated by the applied tension causes necking and breaks as much as possible.

In addition, the pressure bonding material (clad material) from the rolling rolls 3, 3 '
Even when aiming to improve the bondability by heating the material before winding it on the winding reel 4, if the heating is performed by a heating roll as shown in FIG. The same effect as can be obtained, and efficient and stable work can be performed in a small space.

However, in the heating method according to the present invention, if the heating temperature is too high, there is a concern that it may be difficult to adapt, so materials such as aluminum that have a low melting point and tend to soften, or high temperatures such as carbon steel, stainless steel and titanium. It can be said that this is a suitable means for heating a material which is oxidized and colored on the surface when heated to about 300 to 500 ° C. in the former case and 165 ° C. or less in the latter case.

It should be noted that the method of the present invention is not limited to the production of the three-layer clad material as shown in FIG. It goes without saying that it will be done.

In addition, the present invention will be described more specifically by way of examples.

Example First, a pure aluminum coil having a thickness of 2 mm and a width of 200 mm and a pure titanium coil having a thickness of 0.3 mm and a width of 150 mm were prepared.

Next, while continuously rewinding them, the aluminum material and titanium material are both brushed on the joint surface and run, and only the aluminum material is wound around and contacted with a heat-generating roll with a built-in heater to heat and then the two are stacked. Rolling and compression bonding (rolling machine is a 4-roller with a work roll diameter of 80 mmφ and a backup roll diameter of 200 mmφ). ~ 400 ° C) to produce a clad material of aluminum and titanium. The temperature of the aluminum material on the rolling mill entrance side and the clad rolling conditions at this time were as shown in Table 2. Here, the heating temperature is adjusted by the contact length (wrapping length) between the material and the heating roll.
Was changed by adjusting the position of the heating roll.

Next, in order to judge the joining state of the obtained clad material, visual observation of the edge part and the torsion test (test piece size: plate thickness x
5 mm width × 100 mm length) and the results are shown in Table 1 together with the observation result of “material meandering condition during clad material production”. The results of the twist test are displayed as excellent: 5 times or more of 360 ° twist possible, good: 3 to 4 times of 360 ° twist possible.

In Table 2, test Nos. 1 to 4 are examples when the heat treatment on the delivery side of the rolling mill was not performed, and test Nos. 5 and 6 were used.
Is an example of the case where the pressure-bonded material after rolling is subjected to heat treatment with a heating roll. The results shown in (4) clearly show that a clad material with good performance was obtained under good workability.

However, in Test No. 2, the number of twists in the "test piece taken from the plate width end" was sometimes low, so it is suggested that the joint at the strip edge tends to be slightly weakened if the rolling reduction is small. However, even in such a case, the joining state at the strip width edge is sufficiently improved by simply performing a highly efficient heat treatment with a heating roll installed on the exit side of the rolling mill, and it is possible to achieve uniform evenness over the front surface. It can be seen that a high-performance clad material can be obtained (test number 5).

Further, test number 6 is an example of the case where heat treatment is performed by a heating roll installed on the delivery side of the rolling mill as in test number 5, and the heating temperature and tension of the material before rolling are test number 4
Although the clad material was manufactured under the same conditions as above, from this test No. 6, if heat treatment with a heating roll installed on the delivery side of the rolling mill is performed, the rolling reduction is reduced (the rolling load is reduced. It is clear that a clad material with sufficiently satisfactory performance can be obtained even if the load on the rolling mill is reduced. In this case, for example, since the heating temperature is lower than that of Test No. 2 and the rolling reduction is 20% or less, only a clutch material having a worse joining state than that obtained in Test No. 2 is obtained. It was assumed that this was not possible, but it was found that the heat treatment on the delivery side of the rolling mill significantly improved the performance more than expected.

<Summary of Results> As described above, according to the present invention, the heating furnace, which is indispensable when manufacturing the clad material by rolling and press-bonding two or more kinds of metal strip materials, becomes unnecessary and the equipment space is sufficient. In addition to being able to afford, the heating temperature can be adjusted extremely easily and quickly, and the rupture and meandering of the strip material, which leads to reduced productivity, can be suppressed stably, so high quality clad material can be produced at low cost and with high efficiency. It has an extremely useful effect on the industry such that it can be produced.

[Brief description of drawings]

FIG. 1 is a schematic view schematically showing an example of manufacturing a clad material that employs the heating method according to the present invention. FIG. 2 is a schematic diagram showing an example of heating temperature adjustment by a heating roll. FIG. 2 (a) shows an example in which the heating temperature is made relatively low, and FIG. 2 (b) shows the heating temperature. The following are examples of cases in which is relatively high. FIG. 3 is a schematic view schematically showing a manufacturing example of a clad material in which the heating method according to the present invention is adopted in another process location. FIG. 4 is a schematic view schematically showing an example of manufacturing a clad material adopting a conventional heating method, and shows an example in which two kinds of materials are heated to the same temperature and rolled and pressure-bonded. FIG. 5 is a schematic view schematically showing an example of manufacturing a clad material adopting a conventional heating method, and shows an example in which two kinds of materials are heated to different temperatures and rolled and pressure-bonded. In the drawings, 1, 1 '... metal material, 2, 2' ... heating furnace, 3, 3 '... rolling roll, 4 ... take-up reel, 5 ... aluminum strip, 6, 6' ... Other metal strips, 7,7 ′, 7 ″ …… Heating rolls.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Daiji Doi, 12-12, Minatomachi, Joetsu City, Niigata Prefecture, Japan Naoetsu Research Institute, Japan Stainless Co., Ltd. (56) Reference JP-A-57-76133 (JP, A) JP 61-137690 (JP, A)

Claims (1)

[Claims] 1. When manufacturing a clad material by rolling and pressure bonding two or more kinds of metal strip materials, the heating of the materials is carried out by contact with a heating roll, and the contact length between the heating roll and the material is adjusted. A heating method of a raw material at the time of manufacturing a clad material, which is characterized by adjusting a heating temperature.