JP3981495B2 - Hypereutectic Al-Ni-Fe alloy continuous casting rolled coil manufacturing method - Google Patents

Description

【００１３】
【表２】

【００１４】
【表３】

【００１５】
表３の結果より、本発明を用いたものでは０．０６ｍｍまで圧延加工可能であったが、条件が異なる比較例では途中で圧延できないか、スリッター時に破断が生じた。なお、ここで比較例５は従来一般のアルミニウム合金（過共晶でない合金）の連続鋳造圧延で用いられる条件である。
【００１６】
【発明の効果】
以上のように本発明では過共晶Ａｌ−Ｎｉ−Ｆｅ系合金の圧延薄板が製造可能となり、工業上で顕著な効果を奏するものである。
【図面の簡単な説明】
【図１】連続鋳造圧延での凝固状態を示す模式図である。図１（Ｂ）は図１（Ａ）を上方向から見た際の模式図である。
【符号の説明】
１ 凝固界面１（荷重が小さい場合）
２ 凝固界面２（荷重が大きい場合）
３ 連続鋳造圧延ロール表面
４ ロール中心軸[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a hypereutectic Al—Ni—Fe alloy continuous cast rolled coil having excellent rolling properties, and more specifically, a hypereutectic Al— that can be cold-rolled to a thickness of 100 μm or less. The present invention relates to a manufacturing method for obtaining a Ni—Fe alloy continuous casting rolled coil.
[0002]
[Prior art]
When an Fe component is added to an aluminum alloy, strength and heat resistance are improved, and therefore, an Fe component is often added to an aluminum alloy foil or an aluminum alloy fin material. Further, when Ni is added at the same time as Fe, the strength can be improved without lowering the thermal conductivity. Therefore, Ni and Fe are often added simultaneously in the fin material.
Since the solid solution amounts of Ni and Fe in the aluminum alloy are small, when DC (die casting) casting is performed, a coarse intermetallic compound containing Fe is produced at the time of casting, which adversely affects the formability. Therefore, as a manufacturing method for increasing the cooling rate and refining the intermetallic compound produced during casting, a continuous casting and rolling method in which a plate thinner than about 10 mm is directly manufactured from a molten aluminum alloy is performed.
Since the continuous casting and rolling method has a high cooling rate at the time of casting, it is possible to refine the intermetallic compound even in an aluminum alloy to which 1 wt% (hereinafter, wt% is simply referred to as “%”) Fe and Ni are added. Since the obtained alloy is high in strength, it is suitable for thinning the fin material, and because of its high heat resistance, it is difficult to soften due to processing heat during foil rolling, and the foil rolling property is improved.
However, in order to further improve the characteristics, when Fe and Ni are further added to form a hypereutectic Al-Ni-Fe alloy, pinholes are generated when the continuous cast coil is rolled to a thickness of 100 μm or less. However, if it is more severe, it may break during rolling before reaching a thickness of 100 μm, and rolling may not be possible.
[0003]
[Problems to be solved by the invention]
Therefore, in the present invention, a coil obtained by continuous casting from a hypereutectic Al—Ni—Fe alloy can be further thinned to a thickness of 100 μm or less by cold rolling, and defects such as pinholes are generated. It is an object of the present invention to provide a method for producing a hypereutectic Al—Ni—Fe based alloy continuous casting rolled coil that can prevent the above.
[0004]
[Means for Solving the Problems]
This invention is made | formed about the continuous casting rolling method for manufacturing the hypereutectic Al-Ni-Fe-type alloy coil which can be rolled to 100 micrometers or less which is the thickness which can be used as foil or a fin material.
That is, the present invention
(1) A hypereutectic Al—Ni—Fe alloy containing 0.1% or more and 3% or less of Ni and 1.7% or more and 3.2% or less of Fe, and the molten metal temperature is 680 ° C. or more and 780 ° C. or less. As a method for producing a continuous cast and rolled coil for producing an aluminum alloy thin plate having a thickness of 100 μm or less, wherein a load of 7 kN or more per 1 mm width is applied and continuous casting and rolling is performed to a thickness of 2 mm to 4.5 mm,
(2) The method for producing a continuous cast and rolled coil for producing an aluminum alloy sheet according to claim 1, wherein the molten metal temperature is set higher by 40 ° C or more and 90 ° C or less than the liquidus temperature of the alloy, And (3) a hypereutectic Al—Ni—Fe alloy, 1.2% or less of Si, 3.0% or less of Co, 0.3% or less of Zr, 0.3% or less of Ti, 6% One or more of Zn, 0.3% or less of In, 0.3% or less of Sn, 1% or less of Cu, 1.3% or less of Mn, 1% or less of Mg, and unavoidable The present invention provides a method for producing a continuous cast rolled coil for producing an aluminum alloy sheet according to (1) or (2), characterized in that it is a hypereutectic Al-Ni-Fe alloy containing impurities. .
[0005]
DETAILED DESCRIPTION OF THE INVENTION
The production method of the present invention will be described below.
The present invention is directed to a hypereutectic Al—Ni—Fe alloy. This is because a thin plate having excellent characteristics cannot be produced from the alloy by a normal DC casting method or conventional continuous casting and rolling.
Here, the Ni content is 0.1% or more and 3% or less, and the Fe content is 1.7% or more and 3.2% or less. The states of Fe and Ni in aluminum are similar. -Ni hypereutectic, Fe-Al-Fe hypereutectic, and both may be Al-Fe-Ni hypereutectic. Industrially, when both are added, a large amount of Fe is added. That is for most.
This is because when Fe is less than 1.7%, the coil can be manufactured under the conventional continuous casting and rolling conditions. Further, if Ni exceeds 3 wt% or Fe exceeds 3.2%, the alloy cannot be completely cooled to the eutectic temperature during casting, and even if the method of the present invention is used, a plate that can be rolled to a thin plate of 100 μm or less cannot be obtained. Therefore, the upper limit of Fe is set to 3.2%. The lower limit of the amount of Fe that becomes hypereutectic varies slightly depending on other elements added together. However, since there is a variation when manufacturing molten metal industrially, the present invention is applied when the amount is 1.7% or more. This method is effective.
The hypereutectic Al—Ni—Fe-based alloy described above may contain various elements in a range that does not impair the object effects of the present invention, depending on the use of the finally obtained thin plate. For example, Si of 1.2% or less, Co of 3.0% or less, Zr of 0.3% or less, Ti of 0.3% or less, Zn of 6% or less, In of 0.3% or less,. One or more of 3% or less of Sn, 1% or less of Cu, 1.3% or less of Mn, and 1% or less of Mg and unavoidable impurities may be contained. These elements mainly exhibit an important function in characteristics when the alloy is used as a foil or a fin material. Within the above range, the production method of the present invention can be applied. However, in order to reduce the formation of intermetallic compounds described later and to suppress cracking at the time of casting of the alloy, each is 0.7% or less. Si, 2.0% or less Co, 0.2% or less Zr, 0.2% or less Ti, 2% or less Zn, 0.1% or less In, 0.1% or less Sn, 0. It is preferable to use Cu of 5% or less, Mn of 0.6% or less, and Mg of 0.3% or less.
[0006]
In the present invention, the molten alloy is continuously cast and rolled to a thickness of 2 mm to 4.5 mm with a melt temperature of 680 ° C. to 780 ° C. and a load of 7 kN or more per 1 mm of width (lateral width).
In the case of the hypereutectic Al—Ni—Fe alloy used in the present invention, conventionally, an intermetallic compound containing Fe or Ni such as Al—Fe, Al—Ni—Fe, etc. as the primary crystal when continuously cast and rolled is used. Crystallization and the aggregation state of the intermetallic compound cause cracks and the like during cold rolling after continuous casting rolling. Incidentally, in the manufacturing process in which DC casting is performed, since the cooling rate during DC casting is smaller than that of continuous casting and rolling, an intermetallic compound having a size that cannot be compared with continuous casting and rolling occurs, and pinholes and cracks occur during rolling.
Here, when the molten metal temperature is less than 680 ° C., the molten metal temperature is close to the solidus temperature of the alloy, so the solidification state during continuous casting and rolling is easy due to subtle changes in conditions such as subtle temperature variations on the roll surface. It is estimated that the material characteristics in the coil are changed. Further, if the temperature exceeds 780 ° C., the cooling capacity of the continuous casting mill is insufficient, and an intermetallic compound containing Fe or Ni is generated at the center in the thickness direction, causing pinholes and cracks, and energy. It is useless. Here, the molten metal temperature is defined as the temperature of the head box of the casting machine. The head box is a portion that is provided immediately before the molten metal is supplied to the nozzle and pools the hot water in order to stably supply the hot water.
[0007]
For the above reasons, the molten metal temperature is set to 680 ° C. or higher and 780 ° C. or lower, and it is further recommended in the present invention that the molten metal temperature is higher than the liquidus temperature of the alloy by a temperature range of 40 ° C. or higher and 90 ° C. or lower. .
When the temperature difference between the molten metal temperature and the liquidus temperature is less than 40 ° C., the molten metal of continuous casting and rolling is cooled at the nozzle portion that feeds between the rolls, and an intermetallic compound containing Fe and Ni is generated. This is because it flows into the molten metal between the rolls and enters the plate as it is, causing pinholes and cracks. Also, when the molten metal temperature exceeds 90 ° C. from the liquidus, the molten alloy cannot be supercooled to the eutectic temperature, and the hypereutectic Al—Ni—Fe intermetallic compound becomes coarse at the beginning of cooling. This is because it causes pinholes and cracks.
The hypereutectic Al—Ni—Fe alloy melt having such a temperature is continuously cast and rolled to a thickness of 2 mm to 4.5 mm under a load of 7 kN or more per 1 mm width.
[0008]
The thicker the continuous casting and rolling, the fewer defects on the surface and the like that occur during continuous casting and rolling, and the more difficult it is to cause trouble. Therefore, about 5 mm to 10 mm is generally used industrially. In the case of the hypereutectic Al-Ni-Fe alloy, which is the subject of the present invention, when the thickness is large, a normal coil can be produced without apparent defects, but cracks and pinholes occur in the cold rolling process. . This is because, in the case of a hypereutectic Al—Ni—Fe alloy, an intermetallic compound containing Fe such as Al—Fe—Ni may be crystallized as a primary crystal. If it is large, the entire alloy is supercooled and does not solidify, and the intermetallic compound is segregated in the center of the thickness direction of the plate. Depending on the aggregate state of this intermetallic compound, cracks and pinholes are generated in the cold rolling process. This is thought to be caused by the fact that it is easy to do. When the thickness during continuous casting exceeds 4.5 mm, the supercooling is insufficient and segregation of the intermetallic compound is likely to occur. On the other hand, if the thickness is less than 2 mm, cracks and plate thickness fluctuations occur at the time of continuous casting and rolling, and a coil for subsequent cold rolling cannot be manufactured.
[0009]
In producing such a continuous cast and rolled coil having a plate thickness, it is necessary to produce it under conditions that apply a load of 7 kN or more per 1 mm width.
The load in conventional continuous casting and rolling is about 3 kN / mm, and the reason for applying a load exceeding this is as follows. In the conventional method, when the rolling load is less than 7 kN / mm, the solidification interfaces 1 and 2 are solidified at a position close to the center axis of the roll (center of the cast product) as schematically shown in FIG. It becomes the form to do. On the other hand, under the conditions of the present invention, solidification is completed at a position far from the central axis of the roll. Further, the solidification interface in FIG. 1 (A) is schematically shown from the cross-sectional direction, and the solidification interface in the plate width direction when viewed from above is shown in 1 and 2 in FIG. 1 (B). It has a wavy shape. The magnitude of this wave increases as the rolling load decreases. If the rolling load is too small, that is, less than 7 kN / mm, the undulation is performed in this manner, and in the interface portion where solidification is completed at a position close to the roll central axis, Ni and Fe are added to the unsolidified liquid phase. Is easily concentrated, and since the concentrated Ni and Fe have a composition with a large amount of Ni and Fe components, supercooling is less likely to occur, and intermetallic compounds caused by hypereutectic Ni and Fe Is thought to occur densely. This set of intermetallic compounds causes cracks and pinholes during cold rolling.
From the above, in the present invention, continuous casting and rolling is performed with a load of 7 kN or more per 1 mm width, but the upper limit is set to the limit determined by the equipment of the continuous casting and rolling apparatus.
[0010]
Here, the continuous casting and rolling method is an aluminum alloy casting and rolling method known by the Hunter method, the 3C method, and the like, and is sometimes called direct rolling.
The continuous cast and rolled coil produced in the present invention is for making a thin plate of 100 μm or less by cold rolling. Since it is an invention that has solved the problems that occur when rolling to 100 μm or less, it can naturally be rolled as a material with a thickness exceeding 100 μm, but the metal structure obtained under the production conditions of the present invention is necessary in terms of characteristics. Unless it is not, it is not usually necessary to use a coil manufactured under the conditions of the present invention. The manufacturing condition of the present invention is to produce a thin plate under a special rolling load condition by a continuous casting rolling method, and the productivity may be reduced (due to difficulty in forming a wide plate due to high load). is there.
In addition, when cold-rolling the coil manufactured on condition of this invention, you may anneal in the middle of a cold rolling process, and before and after.
[0011]
【Example】
Hereinafter, the present invention will be described in more detail based on examples.
Each aluminum alloy No. 1 having the composition shown in Table 1 was used. From A, B, and C, coils having respective plate thicknesses were produced under the continuous casting and rolling conditions shown in Table 2. The liquidus temperature of the alloy is also shown in Table 2. The roll diameter of the used continuous casting and rolling apparatus is 618 mm, and the width of the manufactured coil is 800 mm. After annealing the obtained coil at 360 ° C. for 2 hours, a coil for fin material having a thickness of 0.06 mm is manufactured by cold rolling, annealing, and cold rolling processes, and the obtained coil is made to have a width of 16 mm. Slitter processing. The cold rolling pass schedule is 6 mm → 2.4 mm → 1 mm → 0.5 mm → 0.3 mm → 0.18 mm → 0.11 mm → 0.06 mm. The thickness of the rolling pass is different.
Table 3 shows the conditions of cold rolling and slitting.
[0012]
[Table 1]

[0013]
[Table 2]

[0014]
[Table 3]

[0015]
From the results of Table 3, rolling using the present invention was possible up to 0.06 mm, but in comparative examples with different conditions, rolling was not possible on the way or fracture occurred during slitting. Here, Comparative Example 5 is a condition used in continuous casting and rolling of a conventional general aluminum alloy (an alloy that is not hypereutectic).
[0016]
【The invention's effect】
As described above, in the present invention, a rolled thin sheet of a hypereutectic Al—Ni—Fe alloy can be produced, and a remarkable effect can be achieved industrially.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a solidified state in continuous casting and rolling. FIG. 1B is a schematic diagram when FIG. 1A is viewed from above.
[Explanation of symbols]
1 Solidification interface 1 (when load is small)
2 Solidification interface 2 (when load is large)
3 Continuous casting roll surface 4 Roll central axis

Claims (3)

A hypereutectic Al—Ni—Fe based alloy containing 0.1 wt% or more and 3 wt% or less of Ni and 1.7 wt% or more and 3.2 wt% or less of Fe is set to a width of 680 ° C. or more and 780 ° C. or less. A method for producing a continuous cast-rolled coil for producing an aluminum alloy sheet having a thickness of 100 μm or less, wherein a continuous casting and rolling is performed to a thickness of 2 mm to 4.5 mm by applying a load of 7 kN or more per 1 mm. The method for producing a continuous cast rolled coil for producing an aluminum alloy sheet according to claim 1, wherein the molten metal temperature is set higher by 40 ° C or more and 90 ° C or less than the liquidus temperature of the alloy. Hypereutectic Al—Ni—Fe-based alloy comprising 1.2 wt% or less Si, 3.0 wt% or less Co, 0.3 wt% or less Zr, 0.3 wt% or less Ti, 6 wt% or less Zn, 1 wt% or less of In, 0.3 wt% or less of Sn, 1 wt% or less of Cu, 1.3 wt% or less of Mn, 1.3 wt% or less of Mg, 1 wt% or less of Mg, and inevitable impurities The method for producing a continuous cast rolled coil for producing an aluminum alloy sheet according to claim 1 or 2, wherein a hypereutectic Al-Ni-Fe alloy is used.

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