Aluminum alloy continuously cast bar, method for manufacturing aluminum alloy continuously cast bar

Abstract

An aluminum alloy continuously cast rod characterized by being a cylindrical aluminum alloy continuously cast rod in which primary crystal Si in a range of 10 μm to 70 μm on the outside of an equivalent circle diameter exists in a range of 0.25 cm 2 in a range of 5 or more and 15 or less.

Description

Technical Field

[0001] This invention relates to aluminum alloy continuous casting rods and a method for manufacturing aluminum alloy continuous casting rods.

[0002] This application claims priority based on Japanese Patent Application No. 2023-215954, filed on December 21, 2023, the contents of which are incorporated herein by reference. Background Technology

[0003] In recent years, the use of aluminum alloys as structural components in various products has been expanding due to their lightweight properties. For example, steel was previously used in general utensils, building materials such as panels, shipbuilding materials, and containers. On the other hand, lightweight, corrosion-resistant, and high-strength aluminum alloy materials have begun to be used in recent years.

[0004] Among these aluminum alloy materials, those used in sliding parts of machinery are required to have excellent wear resistance. Therefore, A390 series aluminum alloys, which are Al-Si hypereutectic alloys, are widely used as aluminum materials (see, for example, Patent Document 1). A390 series aluminum alloys have excellent wear resistance due to their high Si content.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2010-274386 (A) Summary of the Invention

[0008] However, conventional A390 series aluminum alloys have an inverse segregation layer formed during casting in the outer peripheral region, within a few millimeters from the outer periphery inwards. This inverse segregation layer lacks the fine primary Si particles necessary for wear resistance, and therefore, a process called peeling was conventionally used to remove this peripheral region. Consequently, due to the waste of the removed peripheral region (peeling flakes), the actual usable portion of the alloy for wear resistance is less than the cast amount, resulting in low material utilization.

[0009] The present invention was made in view of the following technical background, and its object is to provide: an aluminum alloy continuous casting rod in which fine primary Si is dispersed, which can be used as a wear-resistant material from the center to the outer peripheral surface without removing the outer peripheral region, and a method for manufacturing the aluminum alloy continuous casting rod.

[0010] To address the aforementioned problems, the present invention provides the following means.

[0011] (1) An aluminum alloy continuous casting rod, characterized in that it is a cylindrical aluminum alloy continuous casting rod, wherein in a cross-section perpendicular to the casting direction, the primary Si in the range of 10μm to 70μm outside the equivalent circle diameter, and the primary Si in the range of 0.25cm in length and width of 0.5mm from the casting surface. 2 The area contains a range of 5 to 15.

[0012] (2) The continuous casting rod of aluminum alloy according to (1) is characterized in that the casting is carried out using raw materials having the following alloy composition: containing Si in the range of 10.0% by mass and 18.0% by mass, Fe in the range of 0.50% by mass, Cu in the range of 3.0% by mass and 6.0% by mass, Mn in the range of 0.35% by mass and 0.75% by mass, Ca in the range of 0.0010% by mass and P in the range of 0.001% by mass and 0.1% by mass, with the balance consisting of Al and unavoidable impurities.

[0013] (3) The aluminum alloy continuous casting rod according to (1) or (2) is characterized in that it is used as a constituent material of the sliding component.

[0014] (4) A method for manufacturing an aluminum alloy continuous casting rod, which is a method for manufacturing an aluminum alloy continuous casting rod as described in any one of (1) to (3), characterized in that continuous casting is performed using a continuous casting mold.

[0015] The continuous casting mold comprises:

[0016] The cylindrical mold body has a molten metal inlet at one end and a casting outlet at the other end; and

[0017] A carbon ring is disposed on the inner circumferential surface of the mold body.

[0018] The carbon ring is formed by overlapping a first ring portion disposed on one end side and a second ring portion disposed on the other end side.

[0019] (5) The method for manufacturing aluminum alloy continuous casting rods according to (4), characterized in that the mold body has:

[0020] A lubricating oil supply path, which connects to the second ring portion; and

[0021] A gas supply path, which is connected to the second ring portion and is spaced apart from the lubricating oil supply path,

[0022] The connecting supply section that connects the lubricating oil supply path and the second ring is positioned closer to the first ring than the connecting supply section that connects the gas supply path and the second ring.

[0023] (6) The method for manufacturing an aluminum alloy continuous casting rod according to (5) is characterized in that a groove is formed on the surface of the second ring that overlaps with the first ring for discharging lubricating oil supplied from the lubricating oil supply path to the molten side.

[0024] (7) The method for manufacturing an aluminum alloy continuous casting rod according to (5) or (6) is characterized in that, when viewed from the direction connecting the one end and the other end, the connection between the lubricating oil supply path and the second ring portion and the connection between the gas supply path and the second ring portion are arranged in an overlapping manner.

[0025] (8) A method for manufacturing an aluminum alloy continuous casting rod according to any one of (5) to (7), characterized in that a lubricating oil flow groove is formed along the inner circumferential surface of the second ring portion for lubricating oil supplied from the lubricating oil supply path to pass through.

[0026] (9) A method for manufacturing an aluminum alloy continuous casting rod according to any one of (5) to (8), characterized in that a gas flow groove is formed along the inner circumferential surface of the second ring portion for gas supplied from the gas supply path to pass through.

[0027] (10) A method for manufacturing an aluminum alloy continuous casting rod according to any one of (4) to (9), characterized in that, with respect to the length in the direction connecting the one end and the other end, the second ring is longer than the first ring.

[0028] (11) A method for manufacturing an aluminum alloy continuous casting rod according to any one of (4) to (10), characterized in that at least the second ring portion, of the first ring portion and the second ring portion, has a bulk density of 1.65 to 1.9 g / cm³. 3 It is composed of graphite material with a bending strength of 30MPa to 98MPa.

[0029] (12) The method for manufacturing an aluminum alloy continuous casting rod according to any one of (4) to (11) is characterized in that the supply of lubricating oil and gas is independently controlled.

[0030] According to the present invention, it is possible to provide an aluminum alloy continuous casting rod in which fine primary Si is dispersed, which can be used as a wear-resistant material from the center to the outer peripheral surface without removing the outer peripheral region, and a method for manufacturing the aluminum alloy continuous casting rod. Attached Figure Description

[0031] Figure 1 This is a cross-sectional schematic diagram of the continuous casting mold used in the method for manufacturing aluminum alloy continuous casting rods of the present invention.

[0032] Figure 2 It is used to illustrate the use of having Figure 1 A diagram illustrating a method for manufacturing continuously cast bars using a vertical continuous casting apparatus with a mold for continuous casting.

[0033] Figure 3 This is a magnified cross-sectional diagram of the area near the carbon ring.

[0034] Figure 4A This is a schematic cross-sectional view showing the first and second ring portions that make up the carbon ring separated from each other.

[0035] Figure 4B This is a plan view of the second ring.

[0036] Figure 5 This is a conceptual diagram used to illustrate the effect of the mold for continuous casting involved in this invention.

[0037] Figure 6 This is a graph comparing the shift in lubricating oil pressure due to the number of times the mold is used, in the case of using a continuous casting mold with segmented carbon rings and in the case of using a continuous casting mold with an integral carbon ring.

[0038] Figure 7A These are microscope photographs of an embodiment showing the verification results in the verification example.

[0039] Figure 7B These are microscope images of comparative examples representing the verification results in the verification examples. Detailed Implementation

[0040] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Furthermore, in the drawings used in the following description, for ease of understanding and convenience, some characteristic parts are sometimes shown enlarged, and the dimensions and ratios of the constituent elements are not necessarily the same as actual dimensions. Additionally, the materials, dimensions, etc., illustrated in the following description are examples, and the present invention is not necessarily limited to them; it can be implemented with appropriate modifications without altering its effects.

[0041] [Aluminum Alloy Continuous Casting Rod]

[0042] The aluminum alloy continuous casting rod of this embodiment can be obtained by using the raw materials for aluminum alloy continuous casting rods described later, and by continuously casting using the mold for aluminum alloy continuous casting described later.

[0043] The continuous casting rod of the aluminum alloy in this embodiment is equivalent to a 390 series aluminum alloy in terms of containing more Si.

[0044] The aluminum alloy continuous casting rod of this embodiment (hereinafter sometimes simply referred to as continuous casting rod) is characterized in that it is a cylindrical aluminum alloy continuous casting rod, and in a cross-section perpendicular to the casting direction, the primary Si crystals in the range of 10μm to 70μm outside the equivalent circle diameter are 0.25cm in length and width within a range of 0.5mm from the casting surface. 2 The area contains a range of 5 to 15.

[0045] Furthermore, here, "longitudinal" refers to the direction along the casting direction of the continuous casting rod, and "transverse" refers to the diameter direction that is perpendicular to the casting direction of the continuous casting rod.

[0046] Furthermore, the so-called equivalent circle diameter (HEYWOOD) is denoted by the following formula 1 when the area of ​​a roughly circular cross-section perpendicular to the casting direction is denoted as Area, which is a cylindrical object with irregularities on its outer circumference, such as a continuously cast bar.

[0047]

[0048] (Primary Si is 0.25 cm in length and width of 0.5 mm from the casting surface) 2 (The area contains 5 or more but less than 15)

[0049] Fine primary Si particles contribute to improved wear resistance. In this embodiment, the primary Si particles in the outer peripheral region are made finer per 0.25 cm. 2 With an area of ​​5 or more, wear resistance can be improved even in the outer peripheral region of a continuously cast rod. On the other hand, by increasing the primary Si content in the outer peripheral region to 0.25 cm², wear resistance can be further improved. 2 A surface area of ​​15 or fewer can suppress excessive reduction in tensile strength.

[0050] The aluminum alloy continuous casting rod of this embodiment, with the above-described structure, features fine primary Si particles that contribute to wear resistance, even in the outer peripheral region extending several millimeters from the outer peripheral surface, at a rate of 0.25 cm per unit area. 2 The area has a range of 5 to 15 particles, thus eliminating the need for a peeling process to remove the inverse segregation layer without primary Si formed in the outer peripheral region, as was done previously. Therefore, the continuously cast rod after continuous casting can be used efficiently as a wear-resistant material without waste, up to the outer peripheral surface.

[0051] The aluminum alloy continuous casting rod of this embodiment has excellent wear resistance, and therefore can be used very appropriately as a constituent material for sliding parts such as bearings.

[0052] Raw materials for continuous casting of aluminum alloy bars

[0053] The raw materials for the aluminum alloy continuous casting rod, which are used as manufacturing materials in this embodiment, have the following composition.

[0054] It has the following alloy composition: containing Si in the range of 10.0% to 18.0% by mass, Fe in the range of 0.50% by mass, Cu in the range of 3.0% to 6.0% by mass, Mn in the range of 0.35% to 0.75% by mass, Ca in the range of 0.0010% by mass, and P in the range of 0.001% to 0.1% by mass, with the balance consisting of Al and unavoidable impurities.

[0055] (Si: ≥10.0% by mass and ≤18.0% by mass)

[0056] Si enhances the wear resistance of aluminum alloys by crystallizing as fine primary Si. By ensuring the Si content is 10.0% by mass or more, fine primary Si crystals can crystallize in the outer peripheral region of the continuously cast aluminum alloy bar. Conversely, by keeping the Si content below 18.0% by mass, the reduction in the tensile strength of the aluminum alloy can be suppressed.

[0057] (Fe: less than 0.50% by mass)

[0058] In aluminum alloys, Fe increases the tensile strength of the alloy by crystallizing as fine crystals containing intermetallic compounds such as Al-Mn-Fe-Si, Al-Fe-Si, and Al-Mn-Fe. By maintaining the Fe content within the aforementioned range, it is possible to manufacture target finished products without reducing the machinability and workability of the aluminum alloy raw material.

[0059] (Cu: 3.0% by mass or more and 6.0% by mass or less)

[0060] Cu in aluminum alloys has the function of finely dispersing Mg-Si compounds and increasing the tensile strength of aluminum alloys by precipitating as Al-Cu compounds. By keeping the Cu content within the above-mentioned range, tensile properties can be improved without reducing processability.

[0061] (Mn: ≥0.35% by mass and ≤0.75% by mass)

[0062] In aluminum alloys, manganese (Mn) increases the tensile strength by forming fine granular crystals containing intermetallic compounds such as Al-Mn-Fe-Si, Al-Mn-Fe, Al-Mn, and Al-Mn-Si. By maintaining the Mn content within the aforementioned range, the mechanical properties of the aluminum alloy raw material at room temperature can be improved.

[0063] (Unavoidable impurities)

[0064] Unavoidable impurities are impurities that are unavoidably introduced into the aluminum alloy from the raw materials or manufacturing process. Examples of unavoidable impurities include Ni, Sn, and Be. The content of these unavoidable impurities is preferably no more than 0.1% by mass.

[0065] [Manufacturing method for continuous casting aluminum alloy rods]

[0066] Next, the manufacturing method of the aluminum alloy continuous casting rod according to the above embodiment will be described. First, the continuous casting mold used in the manufacturing method of the aluminum alloy continuous casting rod of this embodiment will be described.

[0067] (Mold for continuous casting)

[0068] Figure 1 This is a cross-sectional schematic diagram of a mold used for continuous casting. Additionally, Figure 2 This is an explanation of the use of [equipment / features]. Figure 1 This diagram illustrates a method for manufacturing aluminum alloy continuous casting bars using a vertical continuous casting apparatus with a continuous casting mold. Additionally, Figure 3 This is a magnified cross-sectional diagram of the area near the carbon ring.

[0069] Figure 1 The continuous casting mold 100 shown is a continuous casting mold used for continuous casting. It includes: a cylindrical mold body 20 with an inlet 21 for molten liquid at one end and an outlet 22 for casting blocks at the other end, and openings at both ends; and a carbon ring 10 disposed on the inner circumferential surface 20A of the mold body 20. The carbon ring 10 is formed by overlapping a first ring portion 10a disposed on one end side and a second ring portion 10b disposed on the other end side.

[0070] exist Figure 1 In the diagram, the direction in which the first ring 10a and the second ring 10b overlap (the direction connecting one end to the other end) is denoted as the Z direction, the direction orthogonal to the Z direction and parallel to the plane of the paper is denoted as the X direction, and the direction orthogonal to the Z direction and perpendicular to the plane of the paper is denoted as the Y direction.

[0071] The carbon ring composed of the first ring and the second ring is sometimes referred to as a "segmented carbon ring".

[0072] The continuous casting apparatus equipped with a continuous casting mold 100 is a vertical continuous casting apparatus that supplies molten liquid L from the upper side of a cylindrical mold body 20 that is open in the vertical direction, and continuously pulls out the casting block S, which is cooled and solidified by the supply of cooling water H, from the lower side of the mold body 20.

[0073] A vertical continuous casting apparatus equipped with a continuous casting mold 100 can be used, for example, for continuously casting aluminum alloy ingots S such as aluminum alloy slabs (rectangular cross-section) and aluminum billets (circular cross-section). Furthermore, the type of ingot S is not limited to the aforementioned aluminum alloys; any metal that can be continuously cast using this vertical continuous casting apparatus is acceptable.

[0074] The mold body 20 has a lubricating oil supply path 31 connected to the second ring portion 10b and a gas supply path 32 connected to the second ring portion 10b and spaced apart from the lubricating oil supply path 31. A connecting supply portion 31a connecting the lubricating oil supply path 31 and the second ring portion 10b is positioned in the Z direction closer to the first ring portion 10a than the connecting supply portion 32a connecting the gas supply path (32) and the second ring portion (10b). Examples of gases supplied from the gas supply path 32 include air, mixed gases (e.g., oxygen + inactive gas), and inactive gases.

[0075] Since the lubricating oil supply path 31 for supplying lubricating oil into the mold and the gas supply path 32 for supplying gas are arranged separately and not shared, it is possible to prevent the influence (interference, backflow, etc.) caused by the pressure difference based on the respective supply amounts of lubricating oil and gas.

[0076] Furthermore, since it has an independent structure with a lubricating oil supply path 31 and a gas supply path 32, the supply of lubricating oil and gas can be controlled independently.

[0077] In the illustrated example, both the connecting supply section 31a and the connecting supply section 32a are arranged in a ring shape within the mold body 20 along the outer peripheral surface of the annular carbon ring 10 (second ring section 10b). However, it could also be configured such that the lubricating oil supply path 31 extends into the second ring section 10b and the connecting supply section 31a is disposed within the carbon ring 10. Similarly, it could be configured such that the gas supply path 32 is inserted into the second ring section 10b and the connecting supply section 32a is disposed within the carbon ring 10. Alternatively, it could be configured such that one or both of the connecting supply sections 31a and 32a are disposed within the carbon ring 10.

[0078] In the illustrated example, when viewed from above in the Z direction, the connecting supply unit 31a and the connecting supply unit 32a are arranged in a non-overlapping position, but they can also be arranged in an overlapping manner.

[0079] Alternatively, a lubricating oil flow groove may be formed in a circumferential shape within the second ring portion 10b for lubricating oil supplied from the lubricating oil supply path 31 to pass through. The circumferential shape may be one full turn or less than one full turn.

[0080] Alternatively, a gas flow channel for gas supplied from the gas supply path 32 can be formed in a circumferential shape within the second ring 10b. The circumferential shape can be one full turn or less than one full turn.

[0081] Since the structure is designed such that the connecting supply part 31a, which connects the lubricating oil supply path 31 and the second ring 10b, is located on the upper section side of the second ring 10b, and the connecting supply part 32a, which connects the gas supply path 32 and the second ring 10b, is located on the lower section side of the second ring 10b, the following effects are achieved.

[0082] Lubricating oil supplied from the lubricating oil supply path 31 descends to the inner circumferential surface 10bAA of the second ring portion 10b due to its own weight via the connecting supply section 31a. Meanwhile, gas supplied from the gas supply path 32 is discharged from the inner circumferential surface 10bAA of the second ring portion 10b via the connecting supply section 32a. Through the gas effect (gas bubbling due to the porous nature of the carbon material), the gas is discharged across a wide area of ​​the carbon-made second ring portion 10b. By discharging the gas in this state, the lubricating oil that descends due to its own weight becomes foamy lubricating oil, forming a heat-insulating layer near the molten metal contact surface of the mold and a sealing layer for the supplied molten metal. This ensures that the molten metal and the inner surface of the mold are in a non-contact state, resulting in a continuous casting rod with a smooth outer surface. Furthermore, due to the synergistic effect, primary cooling is hindered, and the reverse segregation layer around the surface becomes thinner. Moreover, since the gas does not discharge through the carbon ring 10, there are no restrictions on the type of oil, and it can be used for a long time without maintenance as long as no damage occurs.

[0083] The carbon ring 10 is a ring-shaped component made of carbon. The carbon ring 10 is configured to have a structure in which the first ring portion 10a and the second ring portion 10b overlap, as will be described in detail later. The lubricating oil supplied from the lubricating oil supply path 31 is supplied to the inner circumferential surface of the mold through the gap G between the overlap of the first ring portion 10a and the second ring portion 10b.

[0084] In this way, the carbon ring 10 does not have the structure of conventional graphite rings, where lubricating oil seeps through the pores in the graphite material to the inner circumferential surface of the mold. Therefore, the material of the carbon ring 10 does not necessarily need to have pores for lubricating oil to seep out. However, the lubricating oil can be a material that seeps not only from the gap between the overlapping first ring portion 10a and the second ring portion 10b, but also through the pores in the material to the inner circumferential surface of the mold, as is the case with conventional graphite rings. In addition, from the viewpoint of heat resistance of the melt, graphite is preferred as the carbon material constituting the carbon ring 10, but it is not limited to this. Furthermore, the carbon ring 10 can also be manufactured by extruding fine graphite particles in a manner that results in a predetermined pore structure or by pressing them using a hydrostatic method.

[0085] There are no particular limitations on the method of mounting the carbon ring 10 to the mold body 20. For example, it can be mounted to the mold body 20 by thermally inserting it using the difference in the thermal expansion coefficients of the mold body 20 and the carbon ring 10. Since the thermal expansion coefficient of carbon is smaller than that of the metal constituting the mold body 20, when the inner diameter of the mold body 20 is set to be smaller than the outer diameter of the carbon ring 10 at room temperature, and the carbon ring 10 is inserted into the mold body 20, whose inner diameter has expanded due to heating, the carbon ring 10 is fixed to the mold body 20 in a tight state due to the decrease in temperature of the continuous casting mold 100.

[0086] If the installation is performed by hot fitting, the mold body 20 and the carbon ring 10 are tightly fitted together, preventing the formation of gaps between them. Therefore, during continuous casting, the thermal movement from the carbon ring 10 to the mold body 20 is rapid. In addition, since the mold body 20 and the carbon ring 10 are tightly fitted over the entire circumferential area, uneven cooling in the circumferential direction is not generated.

[0087] The carbon ring 10 is a structure formed by overlapping the first ring portion 10a and the second ring portion 10b (a structure formed by fitting together), but the first ring portion 10a and the second ring portion 10b can be carbon materials with the same properties or carbon materials with different properties.

[0088] Of the first ring portion 10a and the second ring portion 10b, at least the second ring portion 10b may have a bulk density of 1.65~1.9 g / cm³. 3 The graphite material has a bending strength of 30 MPa to 98 MPa. This is because the ring made of graphite material with such properties allows sufficient gas to pass through from the gas supply path 32 and has sufficient strength for use in continuous casting of aluminum alloys.

[0089] The carbon ring 10 can also be a structure in which an integral carbon ring is divided into two parts: a first ring portion 10a and a second ring portion 10b.

[0090] In carbon ring 10, the length of the second ring portion 10b in the Z direction ( Figure 3 The reference numeral L2 in the attached diagram is longer than the length of the first ring ( Figure 3 The attached figure is labeled L1 (length).

[0091] Figure 4A This is a cross-sectional schematic diagram showing the first ring portion 10a and the second ring portion 10b constituting the carbon ring 10 spaced apart for ease of explanation. (See diagram below.) Figure 3 As shown, when embedded in the inner circumferential surface of the mold body 20, the mating surfaces (overlapping surfaces, coincident surfaces) 10aA and 10bA of the first ring portion 10a and the second ring portion 10b have only a small gap G formed corresponding to the flatness of their respective mating surfaces (see reference). Figure 3 Conversely, it can also be configured such that the mating surface 10bA of the second ring portion 10b has... Figure 4B The structure shown is a groove or recess (three of which are indicated by reference numeral 10ba) for discharging lubricating oil supplied from the lubricating oil supply path 31 to the molten side.

[0092] exist Figure 4B In the example shown, when viewed from the Z direction, grooves are formed at equal intervals to align the center of the hole with O. However, the number of grooves is not limited to this; additionally, some grooves may have non-equal intervals, and all grooves may also be non-equally spaced. From the viewpoint of uniformly supplying lubricating oil to the inner circumferential surface 20A of the mold body 20, it is preferable that the multiple grooves are arranged at equal intervals. The depth of the groove 10ba can be set, for example, to about 0.015 mm to 2 mm.

[0093] Figure 5 It is a conceptual diagram used to illustrate the function and effect of a mold used in continuous casting.

[0094] Figure 1 The continuous casting mold 100 shown has the following structure: in the Z direction, a connecting supply section 31a connecting the lubricating oil supply path 31 and the second ring portion 10b is disposed on the upper section side of the second ring portion 10b, and a connecting supply section 32a connecting the gas supply path 32 and the second ring portion 10b is disposed on the lower section side of the second ring portion 10b. Furthermore, the carbon ring 10 has a structure in which the first ring portion 10a and the second ring portion 10b overlap in the Z direction.

[0095] Lubricating oil supplied from the lubricating oil supply path 31 is supplied to the inner circumferential surface 10bAA of the second ring 10b via the connecting supply part 31a through the gap G between the first ring 10a and the second ring 10b. The lubricating oil LUB supplied to the inner circumferential surface 10bAA of the second ring 10b descends due to its own weight. On the other hand, gas supplied from the gas supply path 32 is discharged from the inner circumferential surface 10bAA of the second ring 10b via the connecting supply part 32a, and is discharged across the wide surface of the second ring 10b through a gas bubbling effect.

[0096] By venting the gas in this state, the lubricating oil that falls due to its own weight becomes a foamy lubricating oil flub, which becomes a heat insulation layer near the molten contact surface of the mold and a sealing layer for the supplied molten liquid. As a result, the molten liquid and the inner surface of the mold are in a non-contact state, and a continuous casting rod with a smooth outer surface can be obtained.

[0097] Figure 6 This is a graph comparing the shift in pressure (lubricating oil pressure) for lubricating oil supply due to the number of times the mold is used, in the case of using a continuous casting mold equipped with the segmented carbon ring of the present invention and in the case of using a conventional continuous casting mold equipped with a one-piece carbon ring. The carbon ring is made of graphite.

[0098] exist Figure 6 In the graph, the horizontal axis represents the number of times the mold is used (i.e., the number of times continuous casting bars are produced), and the vertical axis represents the ratio of the operating pressure at each number of uses, with the initial pressure of the lubricating oil set to 1.

[0099] A blockage is defined as a pressure ratio of 1.5 between the operating pressure and the initial pressure of the lubricating oil.

[0100] When using the traditional one-piece carbon ring, the lubricating oil pressure exceeded the blockage detection pressure on the fourth use. In contrast, when using the split carbon ring, the ratio of the operating pressure to the initial pressure rose to about 1.03 on the third use, and the lubricating oil pressure did not change even on the twelfth use.

[0101] Thus, it can be seen that when using segmented carbon rings, the clogging of carbon rings is drastically reduced compared to the use of the previous one-piece carbon rings.

[0102] The method for manufacturing an aluminum alloy continuous casting rod according to this embodiment can be carried out by continuously casting by introducing the molten raw material of the aluminum alloy continuous casting rod composed of the above alloy into the continuous casting mold 100.

[0103] An example of casting conditions based on a vertical continuous casting apparatus during such continuous casting is shown in Table 1.

[0104]

[0105] According to the method for manufacturing an aluminum alloy continuous casting rod of this embodiment as described above, it is possible to manufacture primary Si with a length of 0.5 mm and a width of 0.5 mm in each region from the casting surface of 0.25 cm. 2 A continuously cast aluminum alloy rod of the A390 series, containing 5 to 15 particles per square meter. This eliminates the need for a peeling process on the outer periphery, enabling the manufacture of continuously cast aluminum alloy rods that can be efficiently utilized as wear-resistant materials.

[0106] The embodiments of the present invention have been described above, but such embodiments are provided as examples and are not intended to limit the scope of the invention. Such embodiments can be implemented in a variety of other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, and likewise within the scope of the invention as described in the claims and its equivalents.

[0107] Example

[0108] Next, verification examples of the present invention will be described, but the present invention is not particularly limited to these verification examples.

[0109] [Example, Comparative Example]

[0110] The respective continuous casting bars of aluminum alloys for the Examples and Comparative Examples were manufactured under the casting conditions shown in Table 2.

[0111]

[0112] Next, the distribution of fine primary Si particles within a depth range of approximately 1.5 mm from the outer peripheral surface was observed in the continuously cast aluminum alloy rods obtained in the Examples and Comparative Examples. An optical microscope was used for observation. The results were then presented in [the table / document / etc.]. Figure 7A and Figure 7B The photograph is shown in the image. Furthermore, the photograph is a magnified image of the outer periphery of the continuously cast aluminum alloy bar at a magnification of 85x.

[0113] according to Figure 7A The results show that fine primary Si particles, as indicated by black particles in the examples, are dispersed in the outer peripheral region (the rectangular frame portion of the photograph in Figure 7) extending from the outer peripheral surface of the continuous casting rod along the depth direction to approximately 400 μm. Furthermore, among the black particles shown in the photograph, particles with an equivalent circle diameter of 5 μm or more and 60 μm or less are counted as primary Si particles. On the other hand, according to... Figure 7BThe results shown indicate that, in the comparative example, the fine primary Si particles, indicated by black particles, are almost absent in such a peripheral region. These results confirm that the aluminum alloy continuous casting rod of this embodiment, even with fine primary Si dispersed on its peripheral surface, can be used efficiently as a wear-resistant material, including the peripheral region, without requiring a peeling process.

[0114] Industrial availability

[0115] According to the present invention, it is possible to provide an aluminum alloy continuous casting rod in which fine primary Si is dispersed, which can be used as a wear-resistant material from the center to the outer peripheral surface without removing the outer peripheral region, and a method for manufacturing the aluminum alloy continuous casting rod.

[0116] Explanation of reference numerals in the attached figures

[0117] 10 carbon rings

[0118] 10a First Ring Section

[0119] 10b Second Ring

[0120] 20. Casting mold body

[0121] 21 Entry Points

[0122] 22 Casting Exports

[0123] 31 Lubricating oil supply path

[0124] 32 Gas Supply Path

Claims

1. An aluminum alloy continuous casting rod, characterized in that, It is a cylindrical continuously cast aluminum alloy rod. In a cross-section perpendicular to the casting direction, the primary Si crystals in the range of 10μm to 70μm outside the equivalent circular diameter are 0.25cm in length and width within a range of 0.5mm from the casting surface. 2 The area contains a range of 5 to 15.

2. The aluminum alloy continuous casting rod according to claim 1, characterized in that, The casting is carried out using aluminum alloy continuous casting rods made from raw materials having the following alloy composition: containing 10.0% by mass and 18.0% by mass of Si, 0.50% by mass and 0.50% by mass of Fe, 3.0% by mass and 6.0% by mass of Cu, 0.35% by mass and 0.75% by mass of Mn, 0.0010% by mass of Ca, and 0.001% by mass and 0.1% by mass of P, with the balance consisting of Al and unavoidable impurities.

3. The aluminum alloy continuous casting rod according to claim 1 or 2, characterized in that, For use as a material in sliding components.

4. A method for manufacturing an aluminum alloy continuous casting rod, which is a method for manufacturing the aluminum alloy continuous casting rod according to claim 1 or 2, characterized in that, Continuous casting is performed using molds for continuous casting. The continuous casting mold comprises: The cylindrical mold body has a molten metal inlet at one end and a casting outlet at the other end; and A carbon ring is disposed on the inner circumferential surface of the mold body. The carbon ring is formed by overlapping a first ring portion disposed on one end side and a second ring portion disposed on the other end side.

5. The method for manufacturing aluminum alloy continuous casting rods according to claim 4, characterized in that, The mold body has: A lubricating oil supply path, which connects to the second ring portion; and A gas supply path, which is connected to the second ring portion and is spaced apart from the lubricating oil supply path, The connecting supply section that connects the lubricating oil supply path and the second ring is positioned closer to the first ring than the connecting supply section that connects the gas supply path and the second ring.

6. The method for manufacturing aluminum alloy continuous casting rods according to claim 5, characterized in that, A groove is formed on the surface of the second ring that overlaps with the first ring to allow lubricating oil supplied from the lubricating oil supply path to be discharged to the molten side.

7. The method for manufacturing aluminum alloy continuous casting rods according to claim 5, characterized in that, Viewed from the direction connecting one end and the other end, the connection between the lubricating oil supply path and the second ring and the connection between the gas supply path and the second ring are arranged in an overlapping manner.

8. The method for manufacturing an aluminum alloy continuous casting rod according to claim 5, characterized in that, A lubricating oil flow groove is formed along the inner circumferential surface of the second ring portion for lubricating oil supplied from the lubricating oil supply path to pass through.

9. The method for manufacturing an aluminum alloy continuous casting rod according to claim 5, characterized in that, A gas flow channel is formed along the inner circumferential surface of the second ring portion for gas supplied from the gas supply path to pass through.

10. The method for manufacturing an aluminum alloy continuous casting rod according to claim 4, characterized in that, Regarding the length in the direction connecting the one end and the other end, the second ring is longer than the first ring.

11. The method for manufacturing an aluminum alloy continuous casting rod according to claim 4, characterized in that, At least the second ring portion, of the first ring portion and the second ring portion, has a bulk density of 1.65~1.9 g / cm³. 3 It is composed of graphite material with a bending strength of 30MPa to 98MPa.

12. The method for manufacturing an aluminum alloy continuous casting rod according to claim 4, characterized in that, Independently control the supply of lubricating oil and gas.

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