JP3973540B2 - Aluminum alloy sheet having excellent wear resistance and method for producing the same - Google Patents

Description

【００５６】
【表２】

【００５７】
【表３】

【００５８】
【表４】

【００５９】
【表５】

【００６０】
【表６】

【００６１】
【表７】

【００６２】
【表８】

【００６３】
【表９】

【００６４】
【発明の効果】
以上述べたように、本発明のアルミニウム合金板材は低コストで製造可能で、耐摩耗性に優れ、鋳造性、圧延性のいずれにおいても優れた特性を有する。また、板材内部の合金元素量は合金元素が表面に移動した分少ないので、表面および内部ともに合金元素濃度の高い板材に比較して成形性が良好である。そのため、得られたアルミニウム合金板は、ケース、摺動板、フィン、変速機部品、ハードディスクドライブ部品等として、優れた特性を示す材質として使用される。
【図面の簡単な説明】
【図１】図１は、本発明によりアルミニウム合金を鋳造する装置を模式的に示す断面図である。
【図２】図２は、本発明によるアルミニウム合金板材の表面および１／４厚さ部の分析位置を模式的に示す断面図である。
【符号の説明】
１…湯溜
２…注湯ノズル
３…双ベルト式可動鋳型
４…凝固シェル
５…電磁石
６…サンプ（未凝固溶湯）
７…板スラブ
８…双ベルト回転方向
９…溶湯注入口
１０…再溶解領域
１１…シェルから鋳型を離し始める位置
１２…溶湯
１３…凝固完了点
１５…鋳型を離し始める位置の補助ローラ
１６…鋳型を再接触させる位置の補助ローラ
１７…鋳型を再接触させる位置
Ｌ_０…サンプ長さ
Ｌ_１…鋳型を離している距離[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an aluminum alloy plate material that is inexpensive and excellent in wear resistance, and is suitable for use as an automobile member, a general industrial machine or the like by molding by press molding or the like, and a method for producing the same.
[0002]
[Prior art]
Aluminum alloys are used for various members because they are lightweight and have good formability. In addition, the use of Al and Al is further expanding because it can provide excellent wear resistance by containing Si, Fe, Mn, Cr, and the like.
[0003]
In order to obtain such an aluminum alloy sheet, there are a CC method (continuous casting method) and a DC method (semi-continuous casting method). The CC method is a method for obtaining a plate slab having a thickness that can be finish-rolled directly from the molten metal, for example, a thickness of 25 mm or less, and is characterized by omitting hot rough rolling, which is indispensable in a general DC method.
[0004]
As the CC method, a twin roll method, a twin belt method, a block method and the like are known. For example, the twin roll method is a method in which molten metal is injected between a pair of rolls to obtain a plate slab, but the molten metal injected between the rolls is solidified in a very short time due to powerful heat removal from the rolls. It is known that it is a solid solution type plate slab that is completed and the alloy element becomes a solid solution or a fine crystallized product. In addition, although the cooling rate is not as high as that of the twin roll method in the twin belt method and the block method, the molten metal injected between the belts or between the blocks can be solidified in a short time by powerful heat removal from the belt or block. It becomes a slab slab.
[0005]
As a typical example of the above-described CC method, an example of a production method by a twin roll method is shown in Patent Document 1, and an example of a production apparatus is shown in Patent Document 2. In such a method, wear resistance is improved. For this, the alloy composition must be devised.
[0006]
[Patent Document 1]
JP-A-64-73043 (3rd page, especially from upper left column to upper right column)
[Patent Document 2]
Japanese Patent Laid-Open No. 7-68354 (2nd page, especially the first column, paragraph 0002, FIG. 1)
[0007]
[Problems to be solved by the invention]
The cooling rate of the plate slab in the CC method is 10 to 1000 times that of the DC method, and solidification proceeds rapidly from the surface toward the inside.
[0008]
As described above, in order to impart wear resistance to the plate material, it is possible to increase wear resistance by adding elements such as Si, Fe, Mn and Cr, and increasing the amount of addition. However, in the CC method, the plate slab is a solid solution type and the segregation to the center is large, so that the wear resistance corresponding to the amount of the added element cannot be obtained.
[0009]
An object of this invention is to provide the board | plate material which is more excellent in abrasion resistance than the board | plate material obtained by the conventional CC method, and its manufacturing method.
[0010]
[Means for Solving the Problems]
In the present invention, the concentration of the alloy element contributing to wear resistance is made higher than the average concentration of the alloy element in the entire plate material on the surface of the aluminum alloy plate material, thereby reducing the amount of alloy addition and reducing the cost. Abrasion can be secured.
[0011]
That is, the first invention is an aluminum alloy plate material containing Fe 0.1-2.0% and Si 0.05-2.0%, the balance Al and inevitable impurities, the total value Ts of Fe and Si on the plate surface, The aluminum alloy plate material having excellent wear resistance, characterized in that the ratio Ts / To with respect to the total value To of Fe and Si at 1/4 position of the plate material thickness is 1.2 or more.
[0012]
In the present specification, the display unit “%” of the element content (concentration) is “mass%” unless otherwise specified.
[0013]
By concentrating the wear resistance improving element on the surface within the above specified range, the added alloy element can be effectively used for improving the wear resistance.
[0014]
Desirably, the composition further contains one or more of Mn 0.01 to 1.5%, Cr 0.01 to 0.5%, Zr 0.01 to 0.5% and Ni 0.01 to 0.5%, and the balance is inevitable with Al. An aluminum alloy plate made of impurities, the total value TUs of Fe, Si, Mn, Cr, Zr and Ni on the surface of the plate, and Fe, Si, Mn, Cr, Zr at 1/4 of the plate thickness And the ratio TUs / TUo with respect to the total value TUo of Ni is 1.2 or more.
[0015]
Thereby, various kinds of wear resistance improving elements can coexist on the surface of the plate material, and the wear resistance of the plate material can be further improved by the synergistic action of these elements.
[0016]
Further, by adding 0.2% or less of the cast crystal grain refining agent to the aluminum alloy, it is possible to prevent the occurrence of casting cracks more effectively when the casting speed of a thick plate slab is increased by CC casting or the like.
[0017]
The second invention is a method for producing an aluminum alloy plate material by rolling a molten metal of aluminum alloy having any of the above compositions into a plate slab by twin belt type continuous casting, and rolling the plate slab,
In a mold having a mold wall defined by twin belts, the mold wall is once separated from the generated solidified shell and then brought into contact again to complete solidification into a plate slab. A method for producing an aluminum alloy sheet having excellent wear resistance, comprising rolling an aluminum alloy sheet and performing the rolling at a total reduction of 95% or less.
[0018]
By casting the movable mold surface away from the surface of the plate slab for a predetermined time before solidification as the plate slab is finished, the alloy element concentration on the surface of the plate slab can be made higher than the alloy element concentration inside the plate slab, By regulating the total reduction ratio of the plate slab to the plate material, an aluminum alloy plate material having excellent wear resistance can be produced.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
The present invention actively utilizes reverse segregation during solidification of an aluminum alloy, concentrates alloy elements useful for improving wear resistance on the surface, and realizes excellent wear resistance with a small amount of alloy addition. .
[0020]
Usually, when an aluminum alloy melt such as Al-Fe-Si is poured into a mold and comes into contact with the mold wall, as explained in the phase diagram, α crystal having higher purity than the melt composition is first crystallized. Starting from the crystallized product, an α crystal having a higher purity than that of the molten metal in the vicinity is crystallized. By continuously repeating such solidification along the heat removal flow from the mold, a so-called dendritic shell (thin skin) is formed. When the α crystal is crystallized, a part of the alloy element is discharged as a foreign substance from the crystallized material and gathers between the dendrites, so that the alloy element gradually increases in concentration from the surface to the inside.
[0021]
However, when heat removal from the mold is interrupted by once separating the mold wall from the shell according to the present invention when the shell has grown to some extent, the inner wall of the shell in contact with the molten metal having a temperature higher than that of the shell is remelted. At that time, since the shell between the portions of each dendrite is relatively thin, the entire shell thickness is redissolved at that portion. However, each remelted region is a very fine region corresponding to the size of the dendrite, and when viewed macroscopically, the fine remelted region is uniformly and densely dispersed on the shell surface, and the shell itself is The shape is maintained.
[0022]
Along with this remelting, the crystallized material containing Fe, Si, Mn, Cr, Zr, Ni, etc. already formed in the molten metal near the shell at that time is remelted along the dendrite gap. Flow into. As a result, these wear resistance improving elements are concentrated in the remelted region.
[0023]
In this state, when the mold wall is brought into contact with the shell again according to the present invention to complete the solidification in the mold to obtain a plate slab, a plate slab having a concentrated wear resistance improving element on the surface is obtained.
[0024]
If the time for shutting off the heat removal by separating the mold wall from the shell is too long, the size of the remelting area becomes too large, causing surface defects of the plate slab and inability to cast. Therefore, by setting an appropriate blocking time for the shell thickness at the time when the mold wall starts to be separated from the shell, the latent heat of melting of the shell and the sensible heat of the molten metal are balanced so that a fine remelting region is formed on the shell surface. An even and finely dispersed state is obtained.
[0025]
The plate slab obtained in this way has high wear resistance because the surface of the alloy is concentrated and reverse segregated through remelting and resolidification, and the fine segregated areas are evenly and densely distributed. Because of this reverse segregation, the alloy concentration in the inside is low, so it has high formability. As a result, the plate slab and the alloy plate material of the present invention obtained by rolling the slab have surface wear resistance and overall The moldability will be combined.
[0026]
Next, the reasons for limiting the alloy components and their contents in the present invention will be described.
[Fe0.1-2.0%]
Fe improves wear resistance by crystallization of an Al—Fe intermetallic compound and, when coexisting with Si, by crystallization of an Al—Fe—Si intermetallic compound. The amount of addition is limited to 0.1 to 2.0%. If the amount is less than 0.1%, the raw material cost is high, and the amount of crystallized material is small, so the improvement in wear resistance is small. If it exceeds, a large crystallized product is produced at the time of casting, and the rollability of the plate slab and the formability of the alloy plate material are significantly inhibited.
[0027]
Fe crystallizes out as an intermetallic compound and flows into the remelted / resolidified region of the shell surface, thereby enriching (reverse segregation) on the surface and improving the wear resistance of the final alloy sheet.
[Si 0.05-2.0%]
Si crystallizes as simple Si, and when it coexists with Fe, it crystallizes as an Al-Fe-Si intermetallic compound, which contributes to improved wear resistance. The reason for limiting the amount of Si to 0.05-2.0% is that if it is less than 0.05%, the raw material cost will be high, and the effect will be small because the amount that appears as a crystallized substance is small. This is because castability is remarkably lowered and casting defects are increased.
[0028]
Si crystallizes as an intermetallic compound or as a simple substance, and flows into the remelted / resolidified region of the shell surface to concentrate (reverse segregation) on the surface and improve the wear resistance of the final alloy sheet.
[One or more of Mn 0.01 to 1.5%, Cr 0.01 to 0.5%, Zr 0.01 to 0.5%, Ni 0.01 to 0.5%]
Mn, Cr, Zr, Ni are Al- (Fe, Mn, Cr, Ni) -Si intermetallic compounds together with Fe and Si during solidification, or some are Al-Mn, Al-Cr, Al- Crystallization and improvement of wear resistance as intermetallic compounds such as Zr and Al-Ni. This is because when the amount added is less than the lower limit, the improvement in wear resistance is small, and when the amount exceeds the upper limit, a giant crystallized product is generated during casting and cracking occurs during rolling or forming. The total amount of these elements is preferably 2.0% or less in consideration of rollability.
[Casting grain refiner is 0.2% or less]
The cast structure refining agent can prevent the occurrence of casting cracks when CC casting a thick plate slab or increasing the casting speed. To prevent cracking, addition of 0.2% or less of Ti or Ti and B is preferable. Specifically, the above effects are exhibited by the inclusion of 0.002 to 0.2% of Ti, or 0.002 to 0.2% of Ti and 0.0002 to 0.02% of B. Inclusion exceeding the upper limit is not economical because the effect is not significantly improved.
[Inevitable impurities]
Other than the specific elements described above, they are unavoidable impurities, and may be contained within a range not impeding the effects of the present invention. When the allowable content is large, it is preferable that return materials and other low-priced materials can be used. However, as an acceptable standard, the upper limit is Mg and Zn 1.0%, V 0.1%, Ga 0.05%, etc. It is preferable that each element is 0.03%.
[0029]
Next, the manufacturing method of the board | plate material which concerns on this invention is demonstrated.
[0030]
Melting of the molten metal is performed by degassing, sedating, and finely adjusting the composition as necessary after adjusting the composition, and if necessary, adding a crystal grain refining agent in a furnace or in a bowl and continuously casting. Preferably, it is cast into a movable mold after passing through the filter. Examples of the continuous casting method include a twin belt method, a twin roll method, and a block casting method, but the method is not limited. Here, the temperature of the molten metal cast on the movable mold is set to about 710 ° C., which is about 20 degrees higher than usual. The reason for setting it higher is to cause back segregation evenly. At a casting temperature lower than 710 ° C, the total heat of the molten metal is insufficient to sufficiently dissolve the shell, and therefore the back segregation layer is formed in the plate slab. This is because the surface is unevenly distributed, not the entire surface, and it is difficult to obtain uniform wear resistance as a whole. The upper limit is about 760 ° C. to ensure casting stability.
[0031]
With reference to FIG. 1, a preferred method for casting a plate slab according to the present invention is illustrated. In the figure, 1 is a hot water reservoir, 2 is a nozzle, 3 is a movable mold (metal belt), 5 is an electromagnet, 6 is a sump, and 7 is a plate slab.
[0032]
The molten metal melted as described above is transferred from a melting and holding furnace (not shown) to the hot water reservoir 1, and the molten metal is poured between the movable molds 3 and 3 through the nozzle 2. Specifically, the movable molds 3, 3 are metal belts made of iron plate, copper plate or the like. The movable molds 3, 3 are rotated in the direction of the arrow 8 by a driving force (not shown).
[0033]
The molten metal 12 poured between the movable molds 3 and 3 is immediately solidified by the heat removal ability of the movable molds 3 and 3 to form shells 4 and 4. Then, the shell thickness is gradually increased, and solidification is completed at the solidification completion point 13 to form a plate slab 7. 6 is a molten metal or sump sandwiched between the shells 4 and 4. The molten metal 12 poured into the movable mold contacts the mold and immediately solidifies to form the shell 4. The molten metal is removed from the mold and the shells 4 and 4 become thicker over time, and the growth of the shell thickness depends on the ability to remove the movable mold. The initial position 11 for separating the surfaces of the movable molds 3 and 3 from the shells 4 and 4 is appropriately 20 to 50% of the sump length L0 from the molten metal injection port 9 of the movable molds 3 and 3. As a result, the shells 4 and 4 are removed from the mold by heat and melted by the sensible heat of the molten metal inside to form a remelted region 10, and the molten metal 12 leaches out from the dendrite to the outer surface of the shells 4 and 4. The wear resistance on the surface is improved. If the position is less than 20%, the shell thickness is small and the molten metal may melt and blow out from the dendrite, which is undesirable because the slab surface becomes uneven. At a position exceeding 50%, the heat amount of the molten metal in sump 6 is small and it becomes difficult to melt the shell.
[0034]
The distance L1 separating the movable molds 3 and 3 from the shells 4 and 4 is suitably in the range of 30 to 70% of the sump length L0. If the length is less than 30%, the shell is uniformly dissolved by the sensible heat of the molten metal, and it is difficult to leach out between the dendrites. However, if the molten metal temperature during casting is further increased to a temperature exceeding 760 ° C and the amount of heat of the molten metal is increased, reverse segregation is likely to occur, but the cooling of the mold, the position of the movable mold surface away from the shell surface and its length It becomes difficult to manage the casting and the casting becomes unstable. If the length exceeds 70%, the shell may be dissolved and blown out, and the slab surface becomes uneven, which is not preferable.
[0035]
Since FIG. 1 is an explanatory diagram, the situation in which the molten metal 12 leaches out from the dendrite to the outer surfaces of the shells 4 and 4 is coarse, but it seems that it is actually leached in a dense state.
[0036]
To move the movable mold away from the shell before the solidification of the molten metal in the movable mold is completed, electromagnets 5 and 5 are provided as shown in Fig. 1, and the electromagnetic force moves in the opposite direction to the shell. There is a method of pulling the molds 3 and 3 halfway and pulling the movable mold away from the shell. In this case, start auxiliary rollers 15 and 15 are provided at the first position 11 where the surface of the movable molds 3 and 3 is separated from the shells 4 and 4, and end auxiliary rollers 16 and 16 are provided at the end positions 17 and 17, respectively. If the direction of 3 is controlled, the magnetic force of the electromagnets 5 and 5 can be widened, and the length L1 separating the movable molds 3 and 3 from the shells 4 and 4 can be easily managed.
[0037]
The timing to insulate the shell by separating the movable mold surface from the shell surface as described above varies depending on the type of mold used, but the double belt method is 2 to 20 seconds after the molten metal contacts the belt. This can be achieved by separating the inside. The block method can be achieved by separating within 1 to 20 seconds after the molten metal contacts the block. As described above, the molten metal having a high concentration of alloying elements including crystallized substances leached from the shell is solidified at the balance between the melting latent heat of the shell and the sensible heat of the molten metal, but the distance L2 between the shell and the movable mold is small, for example, several hundred. In the case of μm, the leached molten metal may come into contact with the movable mold and solidify to form a plate slab surface.
[0038]
The plate slab thus obtained is rolled without chamfering the surface. The reason for rolling without chamfering the surface is to leave a portion with a high alloy element concentration including crystallized material on the surface that contributes to wear resistance. Although it may be annealed before or during cold rolling, the total reduction ratio until reaching the final product is 95% or less. When rolling exceeds 95%, the portion with low alloying element concentration in the internal structure is exposed between the crystallized products on the product surface, resulting in a decrease in the crystallized material ratio on the surface and deterioration of wear resistance. It is.
[0039]
【Example】
An aluminum alloy sheet was produced according to the present invention. A molten aluminum alloy having the composition shown in Table 1 was used.
[0040]
The CC method was cast using a twin belt casting apparatus as shown in FIG. The casting thickness was 15 mm, and the casting speed (slab drawing speed) was 3 m / min. During casting, the movable mold was pulled away from the surface of the plate slab by pulling the belt inward by electromagnetic force about 2 mm inward from a position 20 cm away from the molten metal injection port of the movable mold. The sump length at this time was 50 cm. The cast plate slab was rolled to a predetermined rolling reduction without chamfering to obtain an alloy plate material.
[0041]
On the other hand, as a comparison, an aluminum alloy plate was manufactured by a method in which the movable mold was not pulled away from the surface of the plate slab in the twin belt method and a casting method by the DC method. Cast thickness by DC method is 406mm, cast ingot is not chamfered, homogenized heat treatment at 530 ° C x 4 hours, hot rolling and cold rolling, and if necessary through intermediate annealing process Rolled to reduction. Table 2 shows the casting conditions.
[0042]
For the aluminum alloy sheet produced by the present invention and the comparative method as described above, the ratio of the total amount of Fe and Si on the sheet surface to the total amount of Fe and Si at the 1/4 position of the thickness as shown in FIG. (Ts / To), or the content ratio of Fe, Si, Mn, Cr, Zr, Ni on the plate surface to the content of Fe, Si, Mn, Cr, Zr, Ni at a position of 1/4 of the thickness ( TUs / TUo). The alloy element content was analyzed by glow discharge emission spectrometry.
[0043]
The content ratio is calculated as Ts / To, where Ts is the total value of Fe and Si on the surface of the plate, and To is the total value of Fe and Si at 1/4 position of the plate thickness. Value. Similarly, the content ratio when one or more of Mn, Cr, Zr, and Ni are included is the total value of Fe, Si, Mn, Cr, Zr, and Ni on the surface of the plate material as TUs. When the total value of Fe, Si, Mn, Cr, Zr and Ni at 1/4 position of the plate material thickness is TUo, the total value ratio is a value calculated by TUs / TUo.
[0044]
The wear resistance was investigated. Wear resistance is a CC method that uses a frictron friction and wear tester, friction speed is 0.139 m / sec, friction distance is 1000 m, pressure load is 100 kg, mating material is SUJ2, and the movable mold is not separated from the shell. The wear amount ratio of each sample was determined by setting the wear amount of the obtained plate material to 1. The results are shown in Table 2.
[0045]
Although the moldability was evaluated with an Erichsen tester, it was better than the conventional method in which the movable mold was not pulled away from the shell.
[0046]
From the results in Table 2, the present invention examples (sample numbers 2, 3, 4, 9, 10, 11, 15, 16, 17, 21, 22, 23, 27, 28, 29, 33, 4, 35, 39, 40, 41, 45, 46, 47, 51, 52, 53, 57, 58, 59, 63, 64, 65, 69, 70, 71, 75, 76, 77, 81, 82, 83, 87, 88, 89, 93, 94, 95) shows that the total amount ratio of elements on the surface is high and the wear amount is low, so that the wear resistance is excellent. It can also be seen that there is no significant difference in wear resistance with and without Ti and B. Thickness of Ti and B (Sample No. 4,11,17,23,29,35,41,47,53,59,65,71,77,83,89,95) is slab thickness Was not thick and the casting speed was not fast, so it was possible to cast without cracking.
[0047]
On the other hand, a comparative example having a high rolling reduction (sample numbers 5, 12, 12, 18, 24, 30, 36, 42, 48, 54, 60, 66, 72, 78, 84, 90, 96) is a shell. It can be seen that even if the movable mold is separated from the above, the total element amount ratio is low, the wear amount is large, and the wear resistance is poor.
[0048]
As a comparative example, the one in which the movable mold is not separated from the shell (sample numbers 6, 13, 19, 25, 31, 37, 43, 49, 55, 61, 67, 73, 79, 85, 91, 97, 101) Even if it is low, the total element amount ratio is low, and it can be seen that the wear amount is large and the wear resistance is poor.
[0049]
For the DC method (sample numbers 1, 8, 14, 20, 26, 32, 38, 44, 50, 56, 62, 68, 74, 80, 86, 92, 98), the rolling reduction is extremely large and the total element It can be seen that the amount ratio is 1.00, the wear amount is large, and the wear resistance is poor.
[0050]
As a comparative example, the CC method having a low casting temperature (Sample No. 7) was unsuitable as a plate material because the plate slab surface was not uniform and the reverse segregation layer was unevenly distributed.
As a comparative example, the CC method with a low Fe content and a movable mold separated from the shell (sample number 99) has a total element ratio within the scope of the present invention, but the cost is low to keep the Fe content low. Becomes higher.
[0051]
As a comparative example, the CC method has a low Si content and the movable mold is not separated from the shell (sample number 101), even if the rolling reduction is low, the element total amount ratio is low, the wear amount is large, and the wear resistance is poor. In addition, the cost increases to keep the Fe content low.
[0052]
As a comparative example, the CC method has a low Si content and the movable mold is separated from the shell (sample number 68), but the total element ratio falls within the scope of the present invention, but the cost is low to keep the Si content low. Get higher.
[0053]
As comparative examples, CC method with high Fe content (Sample No. 102), high Mn content (Sample No. 103), high Zr content (Sample No. 104), high Cr content (Sample) No. 105) and a high Ni content (sample No. 106) were cast with the movable mold separated, but the subsequent rolling could not be measured due to defects such as cracking.
[0054]
As a comparative example, the one cast by the CC method and having a high Si content (Sample No. 107) had poor flowability and a large shrinkage, and could not be cast.
[0055]
[Table 1]

[0056]
[Table 2]

[0057]
[Table 3]

[0058]
[Table 4]

[0059]
[Table 5]

[0060]
[Table 6]

[0061]
[Table 7]

[0062]
[Table 8]

[0063]
[Table 9]

[0064]
【The invention's effect】
As described above, the aluminum alloy sheet of the present invention can be manufactured at low cost, has excellent wear resistance, and has excellent properties in both castability and rollability. Further, since the amount of the alloy element inside the plate material is small because the alloy element has moved to the surface, both the surface and the inside have better formability than a plate material having a high alloy element concentration. Therefore, the obtained aluminum alloy plate is used as a material exhibiting excellent characteristics as a case, a sliding plate, a fin, a transmission component, a hard disk drive component, or the like.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view schematically showing an apparatus for casting an aluminum alloy according to the present invention.
FIG. 2 is a cross-sectional view schematically showing the analysis position of the surface of the aluminum alloy plate material according to the present invention and a ¼ thickness portion.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Hot water reservoir 2 ... Pouring nozzle 3 ... Double belt type movable mold 4 ... Solidified shell 5 ... Electromagnet 6 ... Sump (unsolidified molten metal)
7 ... Plate slab 8 ... Twin belt rotation direction 9 ... Melt inlet 10 ... Remelting region 11 ... Position 12 where mold starts to be released from the shell 12 ... Molten metal 13 ... Solidification completion point 15 ... Auxiliary roller 16 at position where mold starts to be released ... Mold Auxiliary roller 17 at a position where the mold is re-contacted ... Position L _{0 where the} mold is re-contacted ... Sump length L ₁ ... Distance where the mold is separated

Claims (4)

An aluminum alloy plate containing 0.1 to 2.0% Fe and 0.05 to 2.0% Si, the balance being Al and inevitable impurities, the total value Ts of Fe and Si on the surface of the plate, and 1 / th of the thickness of the plate An aluminum alloy sheet with excellent wear resistance, characterized in that the ratio Ts / To with the total value To of Fe and Si at 4 positions is 1.2 or more. Furthermore, it contains one or more of Mn 0.01 to 1.5%, Cr 0.01 to 0.5%, Zr 0.01 to 0.5%, and Ni 0.01 to 0.5%, and the balance is aluminum alloy sheet made of Al and inevitable impurities. The total value TUs of Fe, Si, Mn, Cr, Zr and Ni on the surface of the plate material, and the total value TUo of Fe, Si, Mn, Cr, Zr and Ni at 1/4 position of the plate material thickness 2. The aluminum alloy sheet material having excellent wear resistance according to claim 1, wherein the ratio TUs / TUo to is 1.2 or more. 3. The aluminum alloy sheet excellent in wear resistance according to claim 1, wherein the aluminum alloy sheet further contains 0.2% or less of a cast crystal grain refining agent. A method for producing an aluminum alloy plate material by rolling the molten plate of aluminum alloy according to any one of claims 1 to 3 into a plate slab by twin belt type continuous casting, and rolling the plate slab.
In a mold having a mold wall defined by a double belt, the generated solidified shell is once separated from the mold wall and then brought into contact with the mold wall again to complete solidification into a plate slab. A method for producing an aluminum alloy sheet having excellent wear resistance, wherein the aluminum alloy sheet is rolled without chamfering, and the rolling is performed at a total reduction of 95% or less.

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