WO2012095940A1 - Roue et procédé de fabrication de celle-ci - Google Patents

Roue et procédé de fabrication de celle-ci Download PDF

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Publication number
WO2012095940A1
WO2012095940A1 PCT/JP2011/007368 JP2011007368W WO2012095940A1 WO 2012095940 A1 WO2012095940 A1 WO 2012095940A1 JP 2011007368 W JP2011007368 W JP 2011007368W WO 2012095940 A1 WO2012095940 A1 WO 2012095940A1
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Prior art keywords
wheel
manufacturing
forging
precursor
machining
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PCT/JP2011/007368
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English (en)
Japanese (ja)
Inventor
小野　光太郎
昭二 餅川
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ワシ興産株式会社
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Priority to JP2012543062A priority Critical patent/JPWO2012095940A1/ja
Publication of WO2012095940A1 publication Critical patent/WO2012095940A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
    • C22F1/053—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon of alloys with zinc as the next major constituent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
    • B21K1/00—Making machine elements
    • B21K1/28—Making machine elements wheels; discs
    • B21K1/32—Making machine elements wheels; discs discs, e.g. disc wheels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B23/00—Attaching rim to wheel body
    • B60B23/04—Attaching rim to wheel body by bayonet joint, screw-thread, or like attachments
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B23/00—Attaching rim to wheel body
    • B60B23/06—Attaching rim to wheel body by screws, bolts, pins, or clips
    • B60B23/10—Attaching rim to wheel body by screws, bolts, pins, or clips arranged axially
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B25/00—Rims built-up of several main parts ; Locking means for the rim parts
    • B60B25/04—Rims with dismountable flange rings, seat rings, or lock rings
    • B60B25/14—Locking means for flange rings or seat rings
    • B60B25/20—Arrangement of screws, bolts, or shouldered pins
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/02—Making non-ferrous alloys by melting

Definitions

  • the present invention relates to a wheel and a manufacturing method thereof, and more particularly, to a wheel that is lightweight and excellent in mechanical strength.
  • a vehicle tire is provided with a metallic wheel as a support.
  • the tendency to increase the diameter of a wheel has been remarkable, and the weight has increased accordingly.
  • the increase in weight also increases the unsprung weight of the automobile.
  • the unsprung weight increases, the followability of the suspension is deteriorated, and there is a disadvantage that vibration during traveling increases and maneuvering performance decreases. For this reason, particularly in passenger cars, there is a strong demand for a wheel that is as light as possible even if the diameter of the wheel increases.
  • Examples of such wheels include Mg 0.8 to 1.2%, Cu 0.2 to 0.5%, Mn 0.4 to 0.7%, Fe 0.3% or less, and Cr 0.05 to 0.25%.
  • Aluminum alloy forged road wheel (for example, see Patent Document 1) formed by forging an aluminum alloy with the balance being aluminum, and a vehicle wheel made of a magnesium alloy obtained by straining and recrystallizing a cast magnesium alloy (For example, refer to Patent Document 2), vehicle wheels (for example, refer to Patent Document 3) made of a lightweight material such as an aluminum alloy, a magnesium alloy, or carbon fiber are known.
  • a wheel having a rim portion formed of a composite material made of fiber reinforced resin and a metal disk portion and having a U-shaped cavity in a rim flange is known (for example, Patent Document 4). reference).
  • the weight can be greatly reduced, and the rim deformation can be reduced when subjected to the action of external stress.
  • a preform is also known in which reinforcing fibers are reinforced by winding pre-assembled fibers along two orientations (see, for example, Patent Document 5).
  • Non-Patent Document 1 As an aircraft wheel, one formed by forging an aluminum alloy is known (for example, see Non-Patent Document 1).
  • the conventional wheels including the wheels described in Patent Documents 1 to 5 and Non-Patent Document 1 are not necessarily excellent in mechanical strength.
  • the conventional wheel has a drawback in that the weight of the wheel itself increases because it is necessary to increase the thickness of the wheel in order to ensure sufficient mechanical strength. In particular, when the wheel diameter is large, the weight becomes extremely large.
  • the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a wheel that is lightweight and excellent in mechanical strength and a method for manufacturing the wheel.
  • an international alloy symbol 2000 series aluminum alloy having excellent strength instead of a commonly used international alloy symbol 6000 series aluminum alloy (hereinafter also simply referred to as “6000 series”).
  • 6000 series a commonly used international alloy symbol 6000 series aluminum alloy
  • 7000 series an international alloy symbol 7000 series aluminum alloy
  • the conventional 6000 series is replaced with 2000 series and 7000 series, and the surplus and inner rim parts of the wheel parts are replaced. By reducing the thickness, the weight can be reduced.
  • the Cu component contained in the 2000 series and the 7000 series has a function of improving the strength of the aluminum metal, but has a drawback of poor corrosion resistance.
  • the 2000 series and 7000 series are not used in conventional automobile wheels due to the corrosive nature.
  • the aluminum alloy is specified as 7000 series, the content of the Cu component is limited, and the tensile strength and 0.2% proof stress are set within a predetermined range, thereby providing corrosion resistance. It was found that sex could be improved. Therefore, the present inventors have found that the above problem can be solved by using a wheel that satisfies these requirements, and have completed the present invention.
  • the present invention is a wheel having (1) a disk part, and a rim part formed of an outer rim part and an inner rim part (integral continuous or assembled) provided on the periphery of the disk part.
  • the wheel is made of a 7000 series aluminum alloy.
  • the present invention is (2) a wheel made of an aluminum alloy symbol 7475 aluminum alloy, which is formed by forging, has a Cu content of 1.2 to 1.9 wt%, and has a tensile strength according to JIS-Z2241.
  • the wheel described in (1) above is 450 MPa or more, 0.2% proof stress according to JIS-Z2241 is 400 MPa or more, and Charpy impact value according to JIS-Z2242 is 18.0 J / cm 2 or more. .
  • the present invention is (3) a wheel made of an aluminum alloy symbol 7204 aluminum alloy, which is formed by forging, has a Cu content of 0.2 wt% or less, and has a tensile strength of 300 MPa or more according to JIS-Z2241.
  • the wheel according to the above (1) has a 0.2% yield strength according to JIS-Z2241 of 210 MPa or more and a Charpy impact value according to JIS-Z2242 of 14.3 J / cm 2 or more.
  • the present invention is (4) a wheel made of an aluminum alloy symbol 7204 aluminum alloy, which is formed by casting, has a Cu content of 0.05 to 0.2 wt%, and has a tensile strength according to JIS-Z2241.
  • the wheel according to (1) is 230 MPa or more and has a 0.2% proof stress of 190 MPa or more in accordance with JIS-Z2241.
  • the present invention provides (5) an international alloy symbol 7475 aluminum alloy in the wheel described in (2) above, an international alloy symbol 7204 aluminum alloy in the wheel described in (3) above, or an international alloy symbol in the wheel described in (4) above.
  • the present invention resides in a wheel designed to cope with the design and function of the wheel by adjusting the content of metal element to 7204 aluminum alloy.
  • the thickness of the well portion of the inner rim portion is 2.8 mm or less, and the load symbol 690KG specified by VIA (Japan Vehicle Inspection Association) in the rotational bending fatigue test according to JIS-D4103
  • VIA Japanese Vehicle Inspection Association
  • the present invention relates to (7) a method for producing a wheel as described in (2) or (3) above, wherein the cast billet is heated at 450 to 500 ° C. to stabilize the metal structure;
  • a casting billet subjected to the processing step is formed by forging, and a first forging step is used as a first processed body on which the first rim preliminary member is formed, and the first rim preliminary member of the first processed body is warm-spun.
  • the present invention relates to (8) a method for producing a wheel as described in (2) or (3) above, wherein the casting billet is heated at 450 to 500 ° C. to stabilize the metal structure, A casting billet that has been subjected to a processing step is formed by forging, and a first forging step that is a bottomed cylindrical first workpiece (having a pattern on the bottom or without a pattern), and a cylindrical portion of the first workpiece A spinning process in which pressure is extended by warm spinning to form a second wheel precursor, a heat treatment process to heat-treat the second wheel precursor, and the second wheel precursor subjected to the heat treatment process is machined, And a second machining step for forming a disk portion, an inner rim portion, and an outer rim portion by machining.
  • the present invention relates to (9) a method for producing a wheel as described in (2) or (3) above, wherein the casting billet is heated at 450 to 500 ° C. to stabilize the metal structure, A second forging step in which a cast billet subjected to the processing step is formed by forging, and a third processed body is formed with a patterned disk portion having a forging margin, an outer rim portion, and a third rim preliminary member; A distortion removing process for removing forging distortion of the three processed bodies, and a third rim preliminary member of the third processed body subjected to the distortion removing processes are pressure-extended by warm spinning to form a third inner rim portion.
  • Made of wheels with It resides in the way.
  • the present invention is (10) the method of manufacturing a wheel according to (4) above, in which a molten aluminum alloy is cast into a predetermined mold, and a disk portion, an outer rim portion, a fourth rim preliminary member, And a fourth wheel precursor having an inner rim portion formed by pressure-spreading a fourth rim preliminary member of the fourth workpiece by warm spinning.
  • a wheel manufacturing method comprising: a spinning step, a heat treatment step for heat-treating the fourth wheel precursor, and a fourth machining step for machining the fourth wheel precursor subjected to the heat treatment step. .
  • the present invention is (11) the wheel manufacturing method according to (4) above, wherein a molten aluminum alloy is poured into a predetermined mold and cast to form a disk portion and a rim portion.
  • a second casting step as a wheel precursor, a heat treatment step for heat-treating the fifth wheel precursor, and a fourth machining step for machining the fifth wheel precursor subjected to the heat treatment step. It exists in the manufacturing method of a wheel.
  • the present invention resides in (12) the wheel manufacturing method according to (11), wherein after the second casting step, a spinning step of further pressurizing and extending the rim portion of the fifth wheel precursor by warm spinning is performed.
  • the present invention includes (13) a solution treatment step in which a heat treatment step is 490 ° C. or lower, a quenching step in which quenching is performed, a normal temperature aging step in which aging treatment is performed at room temperature, and an overaging at 100 to 125 ° C.
  • a solution treatment step in which a heat treatment step is 490 ° C. or lower, a quenching step in which quenching is performed, a normal temperature aging step in which aging treatment is performed at room temperature, and an overaging at 100 to 125 ° C.
  • Any one of the above (7) to (12), comprising: a first aging step to be treated; and a second aging step in which the overaging treatment is performed again at a temperature higher by 10 ° C. or more than the temperature of the overaging treatment in the first aging step.
  • the wheel manufacturing method according to any one of the above.
  • the present invention further comprises (14) a surface treatment step of removing notch-like steps on the entire surface after the machining step and performing chamfering on the corners, as described in (7) to (11) above. It exists in the manufacturing method of the wheel as described in any one.
  • the present invention resides in (15) the method of manufacturing a wheel according to (14), wherein the surface treatment step is shot blasting, sand blasting or barrel polishing.
  • the wheel of the present invention is made of an international alloy symbol 7000 series aluminum alloy having excellent strength, so that the thickness of each wheel portion and the inner rim portion, particularly the well portion, can be made thinner than that of the conventional wheel. it can. Therefore, according to the wheel of the present invention, it is lightweight and has excellent mechanical strength.
  • the 7000 series is an international alloy symbol 7475 aluminum alloy (hereinafter also simply referred to as “7475”) or an international alloy symbol 7204 aluminum alloy (hereinafter also simply referred to as “7204”).
  • the 7000 series is preferably 7204.
  • 7475 or 7204 may further contain an additional metal.
  • the Cu content is 1.2 to 1.9 wt%
  • the tensile strength according to JIS-Z2241 is 450 MPa or more
  • the 0.2% proof stress according to JIS-Z2241 is By setting the pressure to 400 MPa or more and setting the Charpy impact value in accordance with JIS-Z2242 to 18.0 J / cm 2 or more, the corrosion resistance is excellent and sufficient mechanical strength can be provided.
  • the Cu content is 0.2 wt% or less
  • the tensile strength according to JIS-Z2241 is 300 MPa or more
  • the 0.2% proof stress according to JIS-Z2241 is 210 MPa.
  • the Cu content is set to 0.05 to 0.3 wt%
  • the tensile strength according to JIS-Z2241 is set to 230 MPa or more, and 0.2% according to JIS-Z2241.
  • the proof stress is 190 MPa or more, corrosion resistance is excellent, and sufficient mechanical strength can be provided.
  • the thickness of the well portion of the inner rim portion is 2.8 mm or less, and the load symbol 690KG specified by VIA (Japan Vehicle Inspection Association) in the rotating bending fatigue test in accordance with JIS-D4103.
  • VIA Joint Vehicle Inspection Association
  • the corrosion resistance is ensured by passing through heat treatment steps (solution treatment step, quenching step, normal temperature aging step, first aging step and second aging step) at a predetermined temperature.
  • heat treatment steps solution treatment step, quenching step, normal temperature aging step, first aging step and second aging step
  • a wheel that can be prevented, is lightweight, and has excellent mechanical strength is obtained.
  • a notch-like step on the entire surface is removed, and the corner portion is subjected to a surface treatment step of performing R chamfering.
  • a tough and excellent design wheel can be obtained.
  • FIG. 1A is a front view showing an example of a wheel according to the present embodiment
  • FIG. 1B is a cross-sectional view taken along line AA in FIG.
  • FIG. 2 is a flowchart showing each step of the wheel manufacturing method according to the first embodiment.
  • (A) of Drawing 3 is a schematic diagram showing before processing of the 1st forge process in a manufacturing method of a wheel concerning a 1st embodiment
  • (b) is a schematic diagram showing after processing of the 1st forge process. is there.
  • FIG. 4 is a cross-sectional view showing a first processed body obtained in a first forging step in the wheel manufacturing method according to the first embodiment.
  • FIG. 5 is a schematic view showing a spinning process in the method for manufacturing a wheel according to the first embodiment.
  • FIG. 6 is a cross-sectional view showing a first wheel precursor in the wheel manufacturing method according to the first embodiment.
  • FIG. 7 is a graph showing temperature conditions of the solution treatment step, the first aging step, and the second aging step in the wheel manufacturing method according to the first embodiment.
  • FIG. 8 is a flowchart showing each step of the wheel manufacturing method according to the second embodiment.
  • FIG. 9 is a schematic view showing the appearance of the treated cast billet before the first forging step and the appearance of the first workpiece after the first forging step in the wheel manufacturing method according to the second embodiment.
  • FIG. 10 is a schematic view showing the appearance of the first processed body before the spinning step and the appearance of the second wheel precursor after the spinning step in the method for manufacturing a wheel according to the second embodiment.
  • FIG. 11 is a flowchart showing each step of the wheel manufacturing method according to the third embodiment.
  • (A) of Drawing 12 is a schematic diagram showing before processing of the 2nd forge process in a manufacturing method of a wheel concerning a 3rd embodiment
  • (b) is a schematic diagram showing after processing of the 2nd forge process. is there.
  • FIG. 13: is sectional drawing which shows the 3rd processed body obtained at the 2nd forge process in the manufacturing method of the wheel which concerns on 3rd Embodiment.
  • FIG. 14A is a schematic diagram showing a state before the distortion removing step in the wheel manufacturing method according to the third embodiment
  • FIG. 14B is a schematic diagram showing a state after the distortion removing step.
  • FIG. 15 is a flowchart showing each step of the wheel manufacturing method according to the fourth embodiment.
  • FIGS. 16A to 16D are schematic views showing a first casting step in the wheel manufacturing method according to the fourth embodiment, and FIG. 16E is a fourth workpiece obtained in the first casting step.
  • FIG. FIG. 17 is a flowchart showing each step of the wheel manufacturing method according to the fifth embodiment.
  • 18A to 18D are schematic views showing a second casting step in the wheel manufacturing method according to the fifth embodiment, and FIG. 18E is a fifth wheel precursor obtained in the second casting step. It is sectional drawing which shows a body.
  • FIG. 19A is a schematic diagram illustrating a first processed body, a first wheel precursor, and a wheel in the method for manufacturing a wheel according to the first embodiment, and FIG.
  • FIG. 19B is a wheel according to the second embodiment. It is the schematic which shows the 2nd wheel precursor and wheel in the manufacturing method of this, (c) is the schematic which shows the 3rd processed body in the manufacturing method of the wheel which concerns on 3rd Embodiment, a 3rd wheel precursor, and a wheel.
  • (D) is a schematic diagram showing a fourth processed body, a fourth wheel precursor, and a wheel in the method for manufacturing a wheel according to the fourth embodiment, and (e) is a wheel according to the fifth embodiment. It is the schematic which shows the 5th wheel precursor and wheel in the manufacturing method of.
  • FIG. 20 is a schematic view showing a modification of the method for manufacturing a wheel according to the third embodiment.
  • (A) of FIG. 21 is the schematic which shows the method of the height measurement in Evaluation 6 of an Example, (b) is the schematic which shows the measurement position of height measurement, (c) is implementation It is the schematic which shows the surface shake measuring method in evaluation 6 of an example.
  • FIG. 1A is a front view showing an example of a wheel according to the present embodiment
  • FIG. 1B is a cross-sectional view taken along line AA in FIG.
  • the wheel 100 according to this embodiment includes a disc portion 20 and a rim portion provided on the periphery of the disc portion 20.
  • the rim portion 30 includes an outer rim portion 9 and an inner rim portion 12.
  • the inner rim portion 12 includes a cylindrical well portion 12a.
  • the disk portion 20 includes a disk-shaped hub portion 11 and spoke portions 10 that extend radially from the hub portion 11.
  • the hub portion 11 is preferably a gently curved curved surface. In this case, since the flow of the raw material at the time of pressing becomes uniform, the particle size of the metal crystal particles is further refined.
  • the hub portion 11 has a disk shape having a curved surface with a gently curved surface, and is provided with bolt insertion holes for inserting bolts when the wheel 100 is fixed to the axle with bolts. Furthermore, there is a space between adjacent spoke portions 10.
  • the 7000 series is used because the 7000 series has better corrosion resistance than the 2000 series when given predetermined characteristics described later.
  • 2014 (2000 series) since 2014 (2000 series) has a high Cu content of 3.9 to 5.0%, it is not preferable from the viewpoint of anticorrosion.
  • Such 7000 series includes Al—Zn—Mg based alloys and Al—Zn—Mg—Cu based alloys.
  • Specific examples include international alloy symbol 7003 aluminum alloy, international alloy symbol 7075 aluminum alloy, international alloy symbol 7475.
  • An aluminum alloy, international alloy symbol 7204 aluminum alloy, etc. are mentioned. Among these, from the viewpoint of 0.2% proof stress and elongation, it is preferable to use 7475 or 7204 when forming by forging and 7204 when forming by casting.
  • the wheel 100 is made of a 7000 series having a Cu content in the above range, so that the surplus thickness of each part of the wheel 100 and the thickness of the inner rim part 12, particularly the well part 12a can be made thinner than that of the conventional wheel. it can.
  • the average particle diameter of the metal crystal particles of the disk portion 20, the outer rim portion 9, and the inner rim portion 12 is preferably 30 ⁇ m or less, more preferably 20 ⁇ m or less, and 15 ⁇ m or less. Even more preferred. When the average particle diameter exceeds 30 ⁇ m, the mechanical strength may be insufficient as compared with the case where the average particle diameter is within the above range.
  • “average particle diameter” is a value measured based on the cutting method of JIS-H0542. The measurement site is near the center of each site.
  • the thickness of the well portion 12a of the inner rim portion 12 is preferably 2.8 mm or less, more preferably 2.5 mm or less, further preferably 2.2 mm or less, More preferably, it is 1.8 mm to 2.2 mm. If the thickness of the well portion 12a exceeds 2.8 mm, the weight increases as compared with the case where the thickness is within the above range, so that the unsprung load increases and vibration during running increases. In addition, mechanical strength may become inadequate that thickness is less than 1.35 mm.
  • the well portion 12a is gradually thickened from the middle to the end portion 13 in order to avoid stress concentration.
  • the wheel 100 preferably achieves 1 million revolutions or more under the load symbol 690KG defined by VIA (Japan Vehicle Inspection Association) in the rotational bending fatigue test in accordance with JIS-D4103 (applied to ECE124). In this case, the occurrence of cracks is suppressed even when subjected to an impact. In the above rules, 100,000 rotations is the acceptance standard value.
  • the Cu content is preferably 1.2 to 1.9 wt%.
  • the mechanical strength becomes insufficient as compared with the case where the Cu content is within the above range, and when the Cu content exceeds 1.9 wt%, the Cu content Compared with the case where a rate exists in the said range, there exists a tendency for corrosion resistance to fall.
  • it is preferable that Cu content rate is 0.2 wt% or less. When Cu content rate exceeds 0.2 wt%, compared with the case where Cu content rate exists in the said range, there exists a tendency for corrosion resistance to fall.
  • the Cu content is preferably 0.05 to 0.2 wt%.
  • the Cu content is less than 0.05 wt%, the mechanical strength becomes insufficient as compared with the case where the Cu content is within the above range, and when the Cu content exceeds 0.2 wt%, the Cu content Compared with the case where the rate is within the above range, castability and corrosion resistance tend to be lowered.
  • 7204 is a special alloy that can be water-cooled or air-cooled in the quenching process during the heat treatment process among aluminum alloys, and can form a wheel by forging or casting.
  • Cu, Mg, and Zn are hardening elements that increase the strength
  • Zr is an element that improves the hardenability and is effective when air-cooled.
  • Ti and Cr are elements that contribute to the refinement of the structure
  • Si is an element that contributes to the elongation.
  • Zn is a factor that makes casting difficult, it is handled sparingly.
  • Cu, Mg, and Zn are components that increase the strength as a hardening element. Further, in order to improve the Charpy value, it is necessary to improve the density of the structure, and in particular, it is necessary to prevent impurities from being mixed with Fe and Si components.
  • the metal element content may be adjusted to 7475 or 7204 to cope with the design and function of the wheel. Such a metal element is not particularly limited.
  • the tensile strength according to JIS-Z2241 is preferably 450 MPa or more, and the 0.2% proof stress according to JIS-Z2241 is 400 MPa or more.
  • the Charpy impact value according to JIS-Z2242 is preferably 18.0 J / cm 2 or more.
  • the tensile strength according to JIS-Z2241 is preferably 300 MPa or more, and the 0.2% proof stress according to JIS-Z2241 is preferably 210 MPa or more.
  • the Charpy impact value according to JIS-Z2242 is preferably 14.3 J / cm 2 or more.
  • the tensile strength according to JIS-Z2241 is preferably 230 MPa or more, more preferably 270 MPa or more, and further preferably 400 MPa or more.
  • the 0.2% proof stress in accordance with JIS-Z2241 is preferably 190 MPa or more.
  • the wheel 100 preferably has an elongation of 8% or more according to JIS-Z2241.
  • the elongation is the ratio of the material in the tensile test of the material.
  • the wheel 100 preferably has a Brinell hardness of 65 HB or more in accordance with JIS-Z2243.
  • the aluminum alloy is not particularly limited, but 7475 or 7204 is preferably used.
  • the wheel manufacturing method according to the first embodiment is formed by forging. For this reason, the mechanical strength of the wheel obtained by the wheel manufacturing method according to the first embodiment is further improved.
  • FIG. 2 is a flowchart showing each step of the wheel manufacturing method according to the first embodiment.
  • the wheel manufacturing method according to the first embodiment includes a homoprocessing step S1 for heating a cast billet to stabilize the metal structure, and a casting billet subjected to the homoprocessing step S1 by forging.
  • a first forging step S2a that is formed into a first processed body on which a first rim preliminary member is formed, and the first rim preliminary member of the first processed body is pressure-extended by warm spinning, and the inner rim portion is Spinning step S3 as the formed first wheel precursor, solution treatment step S4 for solution treatment of the first wheel precursor, quenching step S5 for quenching, and room temperature aging step for aging treatment at room temperature S6, a first aging step S7 for overaging treatment, a second aging step S8 for overaging again at a temperature 10 ° C.
  • the corner portion includes a surface treatment step S10 for performing R chamfering.
  • the heat treatment step includes a solution treatment step S4, a quenching step S5, a normal temperature aging step S6, a first aging step S7, and a second aging step S8.
  • the manufacturing method of the wheel concerning a 1st embodiment, it passes through heat treatment processes (solution treatment process S4, hardening process S5, normal temperature aging process S6, 1st aging process S7, and 2nd aging process S8) at predetermined temperature.
  • solution treatment process S4 hardening process S5, normal temperature aging process S6, 1st aging process S7, and 2nd aging process S8
  • predetermined temperature predetermined temperature.
  • the homo treatment step S1 is a step of heating the cast billet and stabilizing the metal structure. That is, in the homo treatment step S1, a commercially available cylindrical cast billet is heated at a predetermined temperature for a day and a night. Thereby, the defect of a casting composition is removed and a metal crystal particle is homogenized. In particular, when a cast billet made of 7475 or 7204 is used, since a precipitate is present at the grain boundary, it is preferable to perform the homo-processing step S1 for stabilizing the composition of the grain boundary.
  • the treatment temperature in the homo treatment step S1 is preferably 450 to 500 ° C., more preferably 450 ° C. or more and less than 480 ° C.
  • the treatment temperature is less than 450 ° C, the metal crystal particles are insufficiently homogenized as compared with the case where the treatment temperature is within the above range.
  • the treatment temperature exceeds 500 ° C, the treatment temperature is within the above range. Compared with the case of the above, there is a possibility that the metal crystal particles soften and cause recrystallization.
  • first forging process In the first forging step S2a, a cast billet subjected to the homo-processing step S1 (hereinafter referred to as “processed cast billet” for convenience) is formed by forging to form a first processed body on which a first rim preliminary member is formed. It is a process. Note that forging is a processing method in which a cylindrical cast billet is pressed by a press machine having a predetermined thrust to form a rough wheel shape.
  • FIG. 3 is a schematic diagram showing before processing of the 1st forge process in a manufacturing method of a wheel concerning a 1st embodiment
  • FIG. 3B the upper mold 2 is lowered, the treated casting billet 1 is pressurized and compressed, and sandwiched between the upper mold 2 and the lower mold 3.
  • the processed casting billet 1 is formed into a desired shape and becomes the first processed body 4.
  • forging is given by closed forging by hot (forging).
  • the heating conditions at this time are such that the temperature of the treated cast billet is 400 to 550 ° C., preferably 413 to 500 ° C., more preferably 450 to 490 ° C., and the temperature of the mold is around 400 ° C., preferably 350 Set to -420 ° C. This facilitates plastic deformation of the treated cast billet and reduces processing strain due to forging.
  • the pressure condition for pressurization is preferably 9.8 ⁇ 10 3 kN to 88.2 ⁇ 10 3 kN.
  • FIG. 4 is a cross-sectional view showing a first processed body obtained in a first forging step in the wheel manufacturing method according to the first embodiment.
  • a disk portion precursor 4a and a first rim preliminary member 4b continuous with the disk portion precursor 4a are integrally molded.
  • the disk portion 20 is formed from the disk portion precursor 4a, and the outer rim portion 9 and the inner rim portion 12 are formed from the first rim preliminary member 4b.
  • the ratio of the height of the cast billet to the obtained wheel (hereinafter referred to as “forging ratio”) satisfies the following formula.
  • Forging is preferable.
  • the particle size of the metal crystal particles of the wheel is extremely reduced.
  • H1 means the height in the direction in which the forged billet 1 is forged (see FIG. 3A)
  • H2 means the height in the direction in which the wheel is forged. (See (b) of FIG. 1).
  • the forging ratio is more preferably 4 to 12, further preferably 6 to 12, and particularly preferably 6 to 8.
  • the spinning step S3 is a step in which the first rim preliminary member 4b of the first workpiece 4 is pressurized and stretched by warm spinning to form a first wheel precursor having an inner rim portion formed thereon. Specifically, this is a step of forming the inner rim portion 12 erected in the vertical direction around the periphery of the disc portion 20 by narrowing the first rim preliminary member 4b while spinning.
  • Spinning is a kind of flow forming used in various fields, and it is equipped with a rotatable pressing roller that presses the side surface while rotating the material, and the pressing roller moves in parallel to the rotation axis of the material. It is a process to spread the material while letting.
  • the rotation surface of the pressing roller is used in a direction perpendicular to or inclined from the rotation axis of the material.
  • plastic deformation occurs and there is a forging effect, and the alloy structure is refined, so that the material strength is improved.
  • the rim portion can be made thinner and lighter.
  • FIG. 5 is a schematic view showing a spinning process in the method for manufacturing a wheel according to the first embodiment.
  • the first processed body 4 is arranged on the spinning receiving mold 15, and the first processed body 4 is fixed and rotated by pressing the spinning pressing mold 16. Then, the roller 17 is pressed against the outer peripheral portion of the first rim preliminary member 4b of the first workpiece 4 to extend the first rim preliminary member 4b, thereby forming the first wheel having the inner rim portion 12 shown in FIG.
  • the precursor 54 is obtained.
  • FIG. 6 is a cross-sectional view showing a first wheel precursor in the wheel manufacturing method according to the first embodiment. As shown in FIG. 6, the obtained first wheel precursor 54 has an inner rim portion 12 formed on the periphery of the first processed body 4.
  • the spinning step S3 warm spinning is performed under the condition where the first workpiece 4 is heated to 100 ° C. to 200 ° C. By performing warm spinning, recrystallization of the inner rim portion 12 is prevented. After the spinning step S3, a heat treatment step is performed to remove internal strain.
  • the solution treatment step S4 is a step of subjecting the first wheel precursor 54 obtained in the spinning step S3 to a solution treatment.
  • the solution treatment is based on the principle that the solubility between substances generally increases as the temperature increases, and the material is heated to a temperature just below the melting point to dissolve as much solute compound as possible, and then rapidly cooled. It refers to heat treatment.
  • FIG. 7 is a graph showing temperature conditions of the solution treatment step, the first aging step, and the second aging step in the wheel manufacturing method according to the first embodiment.
  • the solution treatment M1 is performed on the first wheel precursor 54 at a temperature of 490 ° C. or less, preferably 450 to 490 ° C. for about 2 hours.
  • the quenching step S5 is a step of quenching by forcibly cooling in a short time.
  • the cooling treatment M2 is forcibly applied to the first wheel precursor 54 that has undergone the solution treatment step S4, and quenching is performed for 4 to 5 minutes.
  • the quenching may be air cooling or water cooling.
  • hot water quenching at 50 to 60 ° C. is preferable.
  • the Brinell hardness is more stable.
  • air cooling can be performed. In this case, there is an advantage that no distortion remains inside.
  • the normal temperature aging step S6 is a step in which the first wheel precursor 54 subjected to the quenching step S5 is subjected to an aging treatment for 24 to 48 hours at normal temperature.
  • the normal temperature means 20 ° C. ⁇ 15 ° C. and is defined in JIS-Z8703.
  • the first aging step S7 is a step of overaging treatment
  • the second aging step S8 is a step of overaging again at a temperature higher by 10 ° C. than the temperature of the overaging treatment in the first aging step S7.
  • the overaging treatment refers to a heat treatment in which the solution material is reheated at an appropriate temperature. Thereby, the solute compound dissolved in the supersaturation forms fine precipitates, and the material becomes extremely hard.
  • the first wheel precursor 54 subjected to the quenching step S5 is subjected to aging treatment at room temperature, and then at a temperature of 100 to 125 ° C., 3 to 8
  • the first overaging process M3 is performed for a time.
  • the temperature of the first wheel precursor 54 subjected to the first aging step S7 is 10 ° C. or more higher than the temperature of the overaging treatment in the first aging step S7, preferably 150 to
  • the second overaging treatment M4 is performed at a temperature of 180 ° C. for 6 to 24 hours.
  • the first wheel precursor 54 is air-cooled M5 to room temperature.
  • the metal structure of the first wheel precursor 54 is strengthened.
  • the first machining step S9a is a step of forming the disk portion 20 and the rim portion 30 by machining the first wheel precursor 54 obtained in the second aging step S8.
  • the drilling process is a so-called milling process by a machining center.
  • a pattern is formed on the first wheel precursor 54, and as a result, a disk portion 20 including a disk-shaped hub portion 11 and spoke portions 10 extending radially from the hub portion 11 is formed.
  • the cutting process is a finishing process in which substantially the entire wheel is cut with a lathe or the like. By cutting, the disk disk portion and the outer rim portion are formed, and the shape of the inner rim portion is adjusted.
  • the disk portion precursor 4a of the first wheel precursor 54 is scraped to form the disk portion 20, but also a pattern such as slight unevenness is formed on the surface. It is also possible to add a design to the wheel or to further reduce the weight by providing a void in the wheel.
  • the first wheel precursor 54 subjected to the first machining step S9a is subjected to surface processing to remove notched steps on the entire surface, and R corners are rounded at the corners. It is a process to be performed. In addition, since 7000 type tends to have low notch fatigue strength, it is more preferable to perform the surface treatment step S10.
  • the surface processing is preferably shot blasting, sand blasting or barrel polishing.
  • patterning such as removal of burrs, surface grinding, and satin processing can be performed.
  • shot blasting examples of the projection method include mechanical, pneumatic, and wet methods, and examples of the projection material include metal particles, polymer particles, and sand.
  • the wheel which concerns on 1st Embodiment is used suitably for vehicles, for example.
  • a vehicle it can be used not only for automobiles but also for motorcycles, unicycles, monorails, and linear motor cars.
  • a wheel having a rim diameter of 13 inches to 25 inches For example, it is suitably used for F1 with a rim diameter of 13 inches, for a rally car with a rim diameter of 20 inches, and for a wheel of a large passenger aircraft with a rim diameter of 23 inches.
  • the weight of the automobile can be reduced, so that the environmental load caused by gasoline or the like can be reduced and the cost can be reduced.
  • the aluminum alloy is not particularly limited, but 7475 or 7204 is preferably used.
  • the wheel manufacturing method according to the second embodiment is formed by forging. For this reason, the mechanical strength of the wheel obtained by the wheel manufacturing method according to the second embodiment is further improved.
  • FIG. 8 is a flowchart showing each step of the wheel manufacturing method according to the second embodiment.
  • the wheel manufacturing method according to the second embodiment includes a homoprocessing step S1 for heating a cast billet to stabilize the metal structure, and a casting billet subjected to the homoprocessing step S1 by forging.
  • a first forging step S2a which is formed into a bottomed cylindrical first processed body, and a spinning step S3 in which a cylindrical portion of the first processed body is subjected to pressure extension by warm spinning to form a second wheel precursor;
  • a second aging step S8 for overaging again at a temperature 10 ° C. or higher than the temperature of the overaging treatment in the first aging step S7, and a second wheel precursor subjected to the second aging step S8 are machined.
  • the bottomed cylindrical first processed body may or may not have a pattern on the bottom.
  • a spinning step S3 is performed on the cylindrical portion to manufacture the second wheel precursor, and instead of the first machining step S9a.
  • the wheel manufacturing method is the same as the wheel manufacturing method according to the first embodiment except that the second machining step S9b in which the disk portion, the inner rim portion, and the outer rim portion are formed by cutting is performed. That is, the homo treatment step S1, the first forging step S2a, the heat treatment step, and the surface treatment step S10 are the same as the wheel manufacturing method according to the first embodiment.
  • the corrosion resistance can be reliably prevented by passing through a heat treatment step at a predetermined temperature.
  • a wheel having excellent mechanical strength can be obtained.
  • a homo treatment step S1 is performed.
  • the cast billet is heated to stabilize the metal structure.
  • FIG. 9 is a schematic view showing the appearance of the treated cast billet before the first forging step and the appearance of the first workpiece after the first forging step in the wheel manufacturing method according to the second embodiment.
  • the first forging step S2a is performed on the columnar processed cast billet, and the bottomed cylindrical first processed body 14 including the cylindrical portion 14b is obtained. It is done.
  • the cylindrical portion 14b of the first processed body 14 obtained in the first forging step S2a is warm-spun, thereby extending the cylindrical portion 14b and forming the second rim preliminary member. This is a step of making a wheel precursor.
  • FIG. 10 is a schematic view showing the appearance of the first processed body before the spinning step and the appearance of the second wheel precursor after the spinning step in the method for manufacturing a wheel according to the second embodiment.
  • the spinning step S3 warm spinning is performed on the cylindrical portion 14b of the bottomed cylindrical first processed body 14 until the cylindrical portion 14b has a length corresponding to the inner rim portion. extend.
  • the 2nd wheel precursor 53 in which the 2nd rim preliminary member of sufficient length was formed is obtained.
  • the second machining step S9b is a step of machining the second wheel precursor obtained in the second aging step S8 to form a disk portion, an inner rim portion, and an outer rim portion by machining.
  • the drilling process is a so-called milling process by a machining center.
  • a pattern is formed on the second wheel precursor 53, and as a result, a disk portion 20 including a disc-shaped hub portion 11 and spoke portions 10 extending radially from the hub portion 11 is formed.
  • the cutting process is a finishing process in which substantially the entire wheel is cut with a lathe or the like. By cutting, an inner rim portion and an outer rim portion are formed, and at the same time, the shape of the disk portion is adjusted.
  • the inner rim portion 12 and the outer rim portion 9 are formed by cutting the second wheel precursor 53, but a pattern such as slight unevenness is formed on the surface.
  • a pattern such as slight unevenness is formed on the surface.
  • the aluminum alloy is not particularly limited, but 7475 or 7204 is preferably used.
  • the wheel manufacturing method according to the third embodiment is formed by forging. For this reason, the mechanical strength of the wheel obtained by the wheel manufacturing method according to the third embodiment is further improved.
  • FIG. 11 is a flowchart showing each step of the wheel manufacturing method according to the third embodiment.
  • the wheel manufacturing method according to the third embodiment includes a homoprocessing step S1 for heating a cast billet to stabilize the metal structure, and a casting billet subjected to the homoprocessing step S1 by forging.
  • a third machining step S9c to be removed, and a surface treatment step S10 for removing a notch-like step on the entire surface and performing R chamfering on the corner after the third machining step S9c are provided.
  • the third wheel precursor manufacturing method passes through the second forging step S2b and the distortion removing step S11, and the third machining step S9a is performed in place of the first machining step S9a. Except for applying the machining step S9c, the wheel manufacturing method is the same as that of the first embodiment. That is, the homo treatment step S1, the spinning step S3, the heat treatment step, and the surface treatment step S10 are the same as the wheel manufacturing method according to the first embodiment.
  • the method for manufacturing a wheel according to the third embodiment similarly to the method for manufacturing a wheel according to the first embodiment, by performing a heat treatment step at a predetermined temperature, corrosion resistance can be reliably prevented, and the weight is reduced. A wheel having excellent mechanical strength can be obtained.
  • the homo processing step S1 is performed.
  • the cast billet is heated to stabilize the metal structure.
  • the second forging step S2b is performed on the treated cast billet.
  • the processed cast billet subjected to the homo-processing step S1 is formed by forging to form a third processed body in which a disk portion having a forging margin, an outer rim portion, and a third rim preliminary member are formed. It is a process.
  • the disk portion is formed by forging. For this reason, a forging margin is formed simultaneously.
  • FIG. 12 is a schematic diagram showing before processing of the 2nd forge process in a manufacturing method of a wheel concerning a 3rd embodiment
  • (b) is a schematic diagram showing after processing of the 2nd forge process. is there.
  • the process casting billet 1 is mounted on the lower die 31 of the press machine provided with the upper die 21 and the lower die 31.
  • the first mold in the wheel manufacturing method according to the first embodiment is different from the first embodiment except that the shapes of the upper mold 21 and the lower mold 31 are different and are provided with patterns for forming the disk portion. This is the same as the forging step S2a.
  • the upper die 21 is lowered, the treated casting billet 1 is compressed by pressure, and is sandwiched between the upper die 21 and the lower die 31. .
  • the processed casting billet 1 is formed into a desired shape, and the third processed body 6 having a disk portion and an outer rim portion is obtained.
  • FIG. 13 is sectional drawing which shows the 3rd processed body obtained at the 2nd forge process in the manufacturing method of the wheel which concerns on 3rd Embodiment.
  • the third processed body 6 includes a disk-shaped hub portion 11, spoke portions 10 that extend radially from the hub portion 11, and a forging margin 6 c formed on the back side of the spoke portion 10.
  • the disc portion 20, the disc portion 20, the outer rim portion 9 extending in the surface direction of the disc portion 20, and the third rim preliminary member 6 b erected on the periphery of the disc portion 20 are integrally formed. Molded. Note that the inner rim portion 12 is formed from the third rim preliminary member 6b.
  • the distortion removing step S11 is a step of removing forging distortion of the third processed body 6 obtained in the second forging step S2b. Specifically, it is a step of removing processing distortion caused by forging that occurs particularly in the spoke portion 10, the outer rim portion 9, and the third rim preliminary member 6b by pressing the third processed body 6. In addition, since the spoke part 10 becomes a location which receives the most extreme stress, it is preferable to perform the distortion removing step S11.
  • FIG. 14A is a schematic diagram showing a state before the distortion removing step in the wheel manufacturing method according to the third embodiment
  • FIG. 14B is a schematic diagram showing a state after the distortion removing step.
  • the upper mold 22 and the knockout part 23a and the lower mold 23 that support the knockout part 23a are assumed to have an increased wheel rim diameter.
  • the third workpiece 6 is placed on a knockout portion 23a of a press machine including Then, under the heating condition, as shown in FIG. 14B, the upper die 22 is lowered, the third processed body 6 is pressurized and compressed, and the upper die 22 and the knockout portion 23a (lower die 23) are compressed. ).
  • the spoke part 10 is pressed in a direction parallel to the wheel rotation axis.
  • the forging margin 6c of the third workpiece 6 is pressed in the vertical direction, and the spoke portion 10 is pressed and stretched in the radial direction (horizontal direction).
  • the forging distortion can be removed by providing the distortion removing step S11, and the durability of the wheel is improved.
  • the diameter of the cross section of the spoke portion extending in the horizontal direction is preferably 4 mm or less.
  • the spinning step S3 is a step in which the third rim preliminary member 6b of the third processed body 6 subjected to the distortion removing step is subjected to pressure extension by warm spinning to form an inner rim portion. In addition, it is the same as that of spinning process S3 in the manufacturing method of the wheel which concerns on 1st Embodiment except using the 3rd processed body 6 instead of the 1st processed body 4.
  • FIG. 1 is the same as that of spinning process S3 in the manufacturing method of the wheel which concerns on 1st Embodiment except using the 3rd processed body 6 instead of the 1st processed body 4.
  • the third rim preliminary member 6b of the third processed body 6 becomes the inner rim portion 12 by the spinning step S3.
  • a third wheel precursor in which the inner rim portion 12 is formed on the third processed body 6 is obtained.
  • the manufacturing method of the wheel concerning a 1st embodiment is used using the 3rd wheel precursor obtained at spinning process S3 instead of the 1st wheel precursor.
  • the solution treatment step S4, the quenching step S5, the normal temperature aging step S6, the first aging step S7, and the second aging step S8 are performed.
  • the third machining step S9c is a step in which the third wheel precursor obtained in the second aging step S8 is machined to form the disk portion 20 from which the forging margin 6c has been removed.
  • Cutting is a process in which substantially the entire wheel is cut with a machining center or a lathe.
  • the forging margin 6c is removed by the cutting process, and as a result, a disk portion 20 including a disc-shaped hub portion 11 and spoke portions 10 extending radially from the hub portion 11 is formed.
  • the shape of the disc part, the inner rim part, and the outer rim part of the wheel is adjusted by finishing cutting.
  • drilling may be performed in addition to cutting. Further, in the third machining step S9c, it is possible to impart a design to the wheel by forming a pattern such as irregularities on the surface, or to further reduce the weight by providing an empty portion on the wheel.
  • the aluminum alloy is not particularly limited, but 7204 is preferably used.
  • the wheel manufacturing method according to the fourth embodiment is formed by casting. Therefore, from the viewpoint of corrosion resistance, the Cu content in the wheel needs to be 0.05 to 0.3 wt%, preferably 0.05 to 0.2 wt%. Thereby, it has sufficient mechanical strength.
  • FIG. 15 is a flowchart showing each step of the wheel manufacturing method according to the fourth embodiment.
  • a molten aluminum alloy is poured into a predetermined mold and cast to form a disk portion, an outer rim portion, and a fourth rim preliminary member.
  • the first casting step S12a, which is the fourth processed body, and the fourth rim preliminary member of the fourth processed body are pressure-extended by warm spinning to form a fourth wheel precursor in which the inner rim portion is formed.
  • the first casting step S12a is performed instead of the homo processing step S1 and the first forging step S2a, and the fourth machining step S9d is performed instead of the first machining step S9a.
  • the spinning step S3, the heat treatment step, and the surface treatment step S10 are the same as the wheel manufacturing method according to the first embodiment.
  • the method for manufacturing a wheel according to the fourth embodiment similarly to the method for manufacturing a wheel according to the first embodiment, by performing a heat treatment step at a predetermined temperature, corrosion resistance can be reliably prevented, and the weight is reduced. A wheel having excellent mechanical strength can be obtained.
  • the first casting step S12a is a step in which a molten aluminum alloy is poured into a predetermined mold and cast to form a fourth workpiece in which a disk portion, an outer rim portion, and a fourth rim preliminary member are formed.
  • FIGS. 16A to 16D are schematic views showing a first casting step in the wheel manufacturing method according to the fourth embodiment, and FIG. 16E is a fourth workpiece obtained in the first casting step.
  • FIG. 16 (a) in the first casting step S12a, the molten 7000 series is poured into a mold of a casting machine composed of an upper mold 41, a horizontal mold 42, and a lower mold 43 to perform casting. Mold.
  • the speed at which the molten 7000 is poured is preferably 65 to 90 mm / min.
  • the crystal grain size of the metal crystal particles tends to be non-uniform compared to the case where the speed is within the above range, and the casting speed is 90 mm / min.
  • it exceeds there exists a possibility that a 4th process body may be damaged easily compared with the case where speed exists in the said range.
  • the 7000 system poured into the casting machine is then homogenized by being heated at 550 ° C. or higher for 6 hours or longer.
  • the cooling is preferably rapid cooling. In this case, there is an advantage that crystal grains become fine.
  • the horizontal mold 42 is removed, and the upper mold 41 is raised to remove the lower mold 43 as shown in FIG. 16 (c).
  • the fourth processed body 7 shown in (e) of FIG. 16 is obtained by removing the fourth processed body from the upper mold 41 and cutting the gate.
  • the fourth processed body 7 in the wheel manufacturing method according to the fourth embodiment includes a disk portion 20 including a disk-shaped hub portion 11, spoke portions 10 extending radially from the hub portion 11, and the disk portion 20.
  • the outer rim portion 9 extending in the surface direction of the disc portion 20 and the fourth rim preliminary member 7b erected on the periphery of the disc portion 20 are integrally molded.
  • a so-called flange portion at the upper end of the inner rim portion 12 is substantially formed.
  • the inner rim portion 12 is formed.
  • FIG. S3 solution treatment step S4, quenching step S5, normal temperature aging step S6, first aging step S7 and second aging step S8 are performed.
  • the fourth machining step S9d is a step of machining the fourth wheel precursor obtained in the second aging step S8.
  • Cutting is a process in which substantially the entire wheel is cut with a machining center or a lathe. By cutting, the shapes of the disc part, the inner rim part, and the outer rim part of the wheel are adjusted.
  • drilling may be performed in addition to cutting. Further, in the fourth machining step S9d, it is possible to impart a design to the wheel by forming a pattern such as irregularities on the surface, or to further reduce the weight by providing a void in the wheel.
  • the aluminum alloy is not particularly limited, but 7204 is preferably used.
  • the wheel manufacturing method according to the fifth embodiment is formed by casting. Therefore, from the viewpoint of corrosion resistance, the Cu content in the wheel needs to be 0.05 to 0.3 wt%, preferably 0.05 to 0.2 wt%. Thereby, it has sufficient mechanical strength.
  • FIG. 17 is a flowchart showing each step of the wheel manufacturing method according to the fifth embodiment.
  • the wheel manufacturing method according to the fifth embodiment includes a fifth wheel precursor in which a molten aluminum alloy is poured into a predetermined form and cast to form a disk portion and a rim portion.
  • Step S10 Obtain.
  • the wheel manufacturing method according to the fifth embodiment is the same as the wheel manufacturing method according to the fourth embodiment except that the second casting step S12b is provided instead of the first casting step S12a and the spinning step S3. . That is, the heat treatment step, the fourth machining step S9d, and the surface treatment step S10 are the same as the wheel manufacturing method according to the fourth embodiment.
  • the corrosion resistance can be reliably prevented by passing through a heat treatment step at a predetermined temperature, and the weight can be reduced. A wheel having excellent mechanical strength can be obtained.
  • the second casting step S12b is a step of casting a molten aluminum alloy into a predetermined mold and casting to form a fifth wheel precursor in which a rim portion including a disc portion, an inner rim portion, and an outer rim portion is formed. It is.
  • FIG. 18A to 18D are schematic views showing a second casting step in the wheel manufacturing method according to the fifth embodiment, and FIG. 18E is a fifth wheel precursor obtained in the second casting step. It is sectional drawing which shows a body.
  • the molten 7000 series is poured into a mold frame of a casting machine composed of an upper mold 51, a horizontal mold 52, and a lower mold 53 for casting. Mold.
  • the second mold in the wheel manufacturing method according to the fourth embodiment except that the upper mold 51 and the lower mold 51 are different in shape and provided with a pattern for forming a rim portion. This is the same as the casting step S12a.
  • the horizontal mold 52 is removed and the upper mold 51 is raised to remove the lower mold 53 as shown in FIG. 18 (c).
  • the fifth wheel precursor 8 shown in FIG. 18 (e) is obtained by removing the fifth wheel precursor from the upper mold 51 and cutting the gate.
  • the fifth wheel precursor 8 in the wheel manufacturing method according to the fifth embodiment includes a disk portion 20 including a disk-shaped hub portion 11 and spoke portions 10 extending radially from the hub portion 11, and the surface direction of the disk portion 20.
  • the outer rim portion 9 extending to the disc portion 20 and the inner rim portion 12 standing on the periphery of the disc portion 20 are integrally molded.
  • the disk portion 20 has a design including the disc-shaped hub portion 11 and the spoke portions 10 extending radially from the hub portion 11, but is not limited thereto.
  • the design may be a spiral shape, a dish shape, a windmill shape, or the like.
  • the quenching step S5 is performed, but the quenching step S5 is not necessarily performed.
  • the normal temperature aging step S6 is performed, but the normal temperature aging step S6 is not necessarily performed.
  • the surface treatment step S10 is performed, but the surface treatment step S10 is not necessarily performed.
  • the number of times of pressing the cast billet with the press machine was multiple times. May be.
  • closed forging is performed, but free forging, die forging, It may be swing forging, extrusion forging, section forging (rotary forging), or the like.
  • die forging includes press forging and hammer forging.
  • the forging conditions are performed by hot forging, it may be warm forging, cold forging, isothermal forging, or the like.
  • the disk portion is not formed when forging, but an incomplete temporary disk portion pattern may be formed. Thereby, the burden at the time of forming the disk part 20 is reduced in the subsequent first machining step.
  • swing forging can be preferably used.
  • the disk portion 20, the outer rim portion 9, and the inner rim portion 12 are integrated into a one-piece wheel. It may be a wheel.
  • an outer rim part and an inner rim part are separately produced, and a mounting seat is provided on the peripheral edge of the disk part. You may wear it. In this case, each is formed by forging or casting.
  • FIG. 19A is a schematic diagram illustrating a first processed body, a first wheel precursor, and a wheel in the method for manufacturing a wheel according to the first embodiment
  • FIG. 19B is a wheel according to the second embodiment. It is the schematic which shows the 2nd wheel precursor and wheel in the manufacturing method of this
  • (c) is the schematic which shows the 3rd processed body in the manufacturing method of the wheel which concerns on 3rd Embodiment, a 3rd wheel precursor, and a wheel.
  • (D) is a schematic diagram showing a fourth processed body, a fourth wheel precursor, and a wheel in the method for manufacturing a wheel according to the fourth embodiment
  • (e) is a wheel according to the fifth embodiment. It is the schematic which shows the 5th wheel precursor and wheel in the manufacturing method of.
  • the first processed body 4 is formed by forging, the first wheel precursor 54 is formed by warm spinning, and the machine The wheel 100 is formed by machining.
  • the second wheel precursor 53 is formed by section forging, and the wheel 100 is formed by machining.
  • the third workpiece 6 is formed by forging, the third wheel precursor 55 is formed by warm spinning, and machining.
  • a wheel 100 is formed.
  • the fourth processed body 7 is formed by casting, the fourth wheel precursor 56 is formed by warm spinning, and machining.
  • a wheel 100 is formed.
  • the length of the inner rim of the fourth processed body 7 is slightly shorter than the length of the inner rim of the completed wheel 100 and is extended by warm spinning. When it is extended, plastic deformation is performed to produce a forging effect, the structure is refined, and the material strength is improved. Therefore, the rim can be formed thinner, so that there is an advantage that the weight can be reduced.
  • the fifth wheel precursor 8 is formed by casting, and the wheel 100 is formed by machining.
  • FIG. 20 is a schematic view showing a modification of the method for manufacturing a wheel according to the third embodiment.
  • a modified example of the wheel manufacturing method according to the third embodiment shown in FIG. 20 is different in that swing forging is performed instead of closed forging.
  • Example 1 A cylindrical cast billet made of 7475 (diameter 204 mm, height 219 mm, weight 20 kg) was prepared. The components shown in 7475 are shown in Table 2.
  • the casting billet was homogenized at a temperature of less than 480 ° C. (preferably 450 ° C.) for about a day and night to homogenize the metal composition (homo processing step S1).
  • forging is performed in two stages with a press machine having a thrust of 7000 tons with a casting billet temperature of 413 ° C. to 490 ° C. and a mold temperature of 350 ° C. to 420 ° C.
  • the body 6 was obtained (see the second forging step S2b, FIGS. 12A and 12B).
  • the forged strain was removed from the third processed body 6 with a press under heating conditions (see the strain removing step S11, (a) and (b) of FIG. 14). Then, the temperature of the third workpiece 6 was heated to 150 to 200 ° C., and the third workpiece 6 was warm-spun to obtain a third wheel precursor (spinning step S3).
  • the third wheel precursor is subjected to solution treatment at a temperature of 450 ° C. for 2 hours (solution treatment step S4), and then quenched with hot water at 50 to 60 ° C. for 4 to 5 minutes (quenching step).
  • solution treatment step S4 solution treatment step
  • quenching step quenching step
  • step S5 aging at room temperature for 24 hours, heating again to gradually raise the temperature, applying a first overaging treatment at a temperature of 100 ° C. to 130 ° C. for 6 hours (first aging step S7), followed by a temperature of 150
  • the second overaging treatment was performed for 9 to 24 hours at a temperature of from 180 ° C. to 180 ° C. (second aging step S8).
  • the forging margin 6c of the obtained third wheel precursor was removed by cutting, and the entire wheel was cut out to adjust the shape, thereby forming a disk portion, an inner rim portion, and an outer rim portion (second). Machining step S9b). After air cooling, notch-like steps on the entire surface were removed, and shot blasting was applied to the corners for R chamfering (surface treatment step S10).
  • a wheel as shown in FIGS. 1A and 1B was obtained.
  • the obtained wheel had a spoke part width of 7.4 mm and an average height of 24.8 mm.
  • the weight was 7.9 kg.
  • the wheel using the conventional 6151 is 9.8 kg, the weight of about 20% is reduced.
  • Example 2 7204 was prepared. The components shown in 7204 are shown in Table 3.
  • a wheel having the same shape was obtained in the same manner as in Example 1 except that a cylindrical cast billet made of 7204 aluminum alloy of the same size was used instead of the cylindrical cast billet made of 7475 aluminum alloy.
  • Example 3 In the quenching step, a wheel was obtained in the same manner as in Example 2 except that quenching by forced air cooling that gave a strong air current to the whole while maintaining the room temperature was performed instead of quenching with warm water.
  • Example 4 7204 was melted at 700 to 750 ° C. to obtain a molten raw material, and poured into a casting mold by a continuous casting method. Then, it was naturally cooled until the temperature reached 300 ° C., and a fourth processed body was obtained in the manner shown in FIG. 16 (see the first casting step S12a, (a) to (e) of FIG. 16).
  • the subsequent spinning step, solution treatment step, quenching step, normal temperature aging step, first aging step, second aging step, first machining step and surface treatment step were performed in the same manner as in Example 1 to obtain a wheel. .
  • quenching with hot water of 50 to 60 ° C. is performed.
  • Example 5 In the quenching step, a wheel was obtained in the same manner as in Example 4 except that quenching by forced air cooling that gave a strong air current to the whole while maintaining the room temperature was performed instead of quenching with warm water.
  • Example 1 A wheel having the same shape was obtained in the same manner as in Example 1 except that a cylindrical cast billet made of 2014 having the same size was used instead of the cylindrical cast billet made of 7475.
  • Table 4 shows a list of wheels obtained in Examples 1 to 5 and Comparative Examples 1 to 3. (Table 4)
  • Example 5 As shown in Table 5, in the strength test according to JIS-Z2241, it was found that the wheel using 7475 of Example 1 was the most excellent. In particular, the air-cooled wheel of Example 3 showed a high numerical value even in the spoke portion where distortion remained easily. From this result, it is considered that a fine grain superplasticity phenomenon exceeding plastic deformation occurs in the 7000 series.
  • the above elongation and Charpy value are considered to be improved by further miniaturizing the metal structure.
  • a method of refining the metal structure low-pressure casting is performed, the cooling effect after casting is accelerated, the effect of forced air cooling is enhanced by increasing the amount of Zr component added and improving the hardenability,
  • the elements include using Ti and B as additives.
  • Example 3 The wheel obtained in Example 1 was subjected to a rotating bending fatigue test according to JIS-D4103 (applied to ECE124). Since it is for light vehicles, the bending moment was 1170 N ⁇ m. The specified value under the condition of VIA690KG is 100,000 times as the maximum load in the passenger car. As a result, the wheel of Example 1 achieved 9.40 million times, which is 90 times the specified value. Also, no defects such as cracks have occurred.
  • the wheels obtained in Examples 4 and 5 were subjected to a rotating bending fatigue test according to JIS-D4103 (applied to ECE124). Since it is for light vehicles, the bending moment was 1170 N ⁇ m. As a result, the wheels of Examples 4 and 5 achieved 1 million times. Also, no defects such as cracks have occurred.
  • Table 7 shows the maximum value, the minimum value, and the average value of the 14 material strength test results collected from the rim portion, the inner flange portion, the spoke portion, the outer flange portion, the hub portion, and the like in the wheel of Example 3.
  • the wheel of the present invention is suitably used for applications such as vehicles for vehicles, aircraft vehicles, and railway vehicles using linear motors currently being developed for practical use.
  • the vehicle when used for a vehicle, the vehicle can be reduced in weight by reducing the unsprung weight. For this reason, the environmental load by gasoline etc. can be reduced.
  • the wheel rim or disc during traveling even if an impact occurs on the wheel rim or disc during traveling, it can be prevented from being damaged. Does not grow. When a crack occurs, the tire air pressure gradually decreases, so that it is possible to provide a highly safe wheel such that the operator notices abnormally and does not lead to a major accident.
  • Solution treatment step S5 ... quenching step S6 ... normal temperature aging step S7 ... first aging step S8 ... second aging step S9a ... first machining step S9b ... second machining step S9c ... -3rd machining process S9d ... 4th machining process S10 ... Surface treatment process S11 ... Distortion removal process S12a ... 1st casting process S12b ... 2nd casting process

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Forging (AREA)

Abstract

[Problème] L'invention vise à concevoir une roue qui est d'un faible poids et qui possède une excellente résistance mécanique ainsi qu'un procédé de fabrication de celle-ci. [Solution] La présente invention concerne une roue (100) ayant : une section disque (20) ; et une section jante qui est mise en œuvre sur une périphérie de la section disque (20) de manière continue et intégrale ou par assemblage et qui est configurée à partir d'une section jante extérieure et d'une section jante intérieure agencée à la verticale sur la section jante extérieure, la roue (100) étant réalisée à partir d'un alliage d'aluminium de la série 7000 du système international de désignation pour les alliages. Quand la roue (100) est réalisée à partir d'un alliage d'aluminium de la série 7475 du système international de désignation pour les alliages, il est préférable que la roue (100) soit moulée par un procédé de forgeage. Quand la roue (100) est réalisée à partir d'un alliage d'aluminium de la série 7204 du système international de désignation pour les alliages, il est préférable que la roue (100) soit moulée par un procédé de forgeage ou de moulage.
PCT/JP2011/007368 2011-01-10 2011-12-28 Roue et procédé de fabrication de celle-ci WO2012095940A1 (fr)

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CN110508737A (zh) * 2019-08-26 2019-11-29 南京理工大学 一种轮毂挤压成形方法
US11103919B2 (en) 2014-04-30 2021-08-31 Alcoa Usa Corp. 7xx aluminum casting alloys, and methods for making the same
CN114289587A (zh) * 2021-12-31 2022-04-08 兰天车轮(连云港)有限公司 一种农业车轮的制造工艺及装置
CN116516189A (zh) * 2023-06-28 2023-08-01 中北大学 一种镁合金车轮铸锻成形方法
CN117549013A (zh) * 2024-01-10 2024-02-13 江苏凯特汽车部件有限公司 一种新能源汽车铝车轮铸造旋压制造方法

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11103919B2 (en) 2014-04-30 2021-08-31 Alcoa Usa Corp. 7xx aluminum casting alloys, and methods for making the same
CN110508737A (zh) * 2019-08-26 2019-11-29 南京理工大学 一种轮毂挤压成形方法
CN110508737B (zh) * 2019-08-26 2021-09-21 南京理工大学 一种轮毂挤压成形方法
CN114289587A (zh) * 2021-12-31 2022-04-08 兰天车轮(连云港)有限公司 一种农业车轮的制造工艺及装置
CN114289587B (zh) * 2021-12-31 2022-09-23 兰天车轮(连云港)有限公司 一种农业车轮的制造工艺及装置
CN116516189A (zh) * 2023-06-28 2023-08-01 中北大学 一种镁合金车轮铸锻成形方法
CN116516189B (zh) * 2023-06-28 2023-10-20 中北大学 一种镁合金车轮铸锻成形方法
CN117549013A (zh) * 2024-01-10 2024-02-13 江苏凯特汽车部件有限公司 一种新能源汽车铝车轮铸造旋压制造方法
CN117549013B (zh) * 2024-01-10 2024-03-26 江苏凯特汽车部件有限公司 一种新能源汽车铝车轮铸造旋压制造方法

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