Aluminum alloy and process for producing aluminum alloy extrusions

Abstract

An aluminum alloy has a composition consisting of Si: 0.03 to 0.6 mass %, Fe: 0.1 to 0.7 mass %, Cu: 0.05 to 0.20 mass %, Mn: 1.0 to 1.5 mass %, Mg: 0.01 to 0.1 mass %, Zn: 0 to 0.1 mass %, Ti: 0 to 0.1 mass %, and the balance being Al and inevitable impurities.

Claims

1. An aluminum alloy having a composition consisting of Si: 0.03 to 0.6 mass %, Fe: 0.1 to 0.7 mass %, Cu: 0.05 to 0.17 mass %, Mn: 1.06 to 1.20 mass %, Mg: 0.02 to 0.05 mass %, Zn: 0 to 0.02 mass %, Ti: 0.01 to 0.02 mass %, and the balance being Al and inevitable impurities.

2. A production method of an aluminum alloy extruded member, wherein an aluminum alloy billet having the composition as recited in claim 1 is extruded.

3. The production method of an aluminum alloy extruded member as recited in claim 2, wherein the extruded member is an aluminum alloy extruded tube for a photoconductor drum substrate.

4. A production method of a photoconductor drum substrate, wherein an aluminum alloy extruded tube for a photoconductor drum substrate obtained by the production method of an aluminum alloy extruded member as recited in claim 3 is drawn.

5. A production method of a photoconductor drum substrate, wherein an aluminum alloy extruded tube for a photoconductor drum substrate obtained by the production method of an aluminum alloy extruded member as recited in claim 3 is ironed.

6. An aluminum alloy extruded member having a composition consisting of Si: 0.03 to 0.6 mass %, Fe: 0.1 to 0.7 mass %, Cu: 0.05 to 0.17 mass %, Mn: 1.06 to 1.2 mass %, Mg: 0.02 to 0.05 mass %, Zn: 0 to 0.02 mass %, Ti: 0.01 to 0.02 mass %, and the balance being Al and inevitable impurities.

7. The aluminum alloy extruded member as recited in claim 6, wherein the extruded member is an aluminum alloy extruded tube for a photoconductor drum substrate.

8. A photoconductor drum substrate made of an aluminum alloy having a composition consisting of Si: 0.03 to 0.6 mass %, Fe: 0.1 to 0.7 mass %, Cu: 0.05 to 0.17 mass %, Mn: 1.06 to 1.2 mass %, Mg: 0.02 to 0.05 mass %, Zn: 0 to 0.02 mass %, Ti: 0.01 to 0.02 mass %, and the balance being Al and inevitable impurities.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic cross-sectional view showing an extrusion device used in a production method of an aluminum alloy extruded member according to an embodiment of the present invention in a state in the middle of an extrusion process.

(2) FIG. 2 is a schematic cross-sectional view showing a drawing device used for drawing an aluminum alloy extruded tube as an aluminum alloy extruded member in a state in the middle of a drawing process.

EMBODIMENTS FOR CARRYING OUT THE INVENTION

(3) Next, an embodiment of the present invention will be explained with reference to the attached drawings.

(4) An aluminum alloy according to an embodiment of the present invention has a composition consisting of Si: 0.03 to 0.6 mass %, Fe: 0.1 to 0.7 mass %, Cu: 0.05 to 0.20 mass %, Mn: 1.0 to 1.5 mass %, Mg: 0.01 to 0.1 mass %, Zn: 0 to 0.1 mass %, Ti: 0 to 0.1 mass %, and the balance being Al and inevitable impurities. The aluminum alloy basically has a composition close to aluminum alloy A3003 as defined by JIS (Japanese Industrial Standards) and includes 0.01 to 0.1 mass % of Mg as an essential element.

(5) In this embodiment, this aluminum alloy is especially suitably used as an extruding material. Specifically, by extruding this aluminum alloy billet, an aluminum alloy extruded member is especially suitably produced. This extruded member is an aluminum alloy extruded tube (extruded blank tube) having a circular cross-section for use as a photoconductor drum substrate. By drawing or ironing the extruded tube, a drawn tube or an ironed tube as a non-machined tube is produced. Subsequently, by subjecting the drawn tube or the ironed tube to a predetermined process, a photoconductor drum substrate is produced.

(6) As shown in FIG. 1, the extrusion device 10 used for extruding an aluminum alloy billet 1 is not specifically limited, and is a known device. That is, the extrusion device 10 is equipped with a container 11, an extrusion die 12, a stem 17, etc. The extrusion die 12 is, for example, a porthole die which is a combination of a male die 13 and a female 14, and includes a forming gap 15 having an annular cross-section formed between a male bearing portion 13a and a female bearing portion 14a disposed facing each other. The male bearing portion 13a and the female bearing portion 14a are configured to form an inner surface and an outer surface of the extruded tube 2, respectively.

(7) A method of extruding the aluminum alloy billet 1 using the extrusion device 10 is not specifically limited, and the extrusion process is performed according to a known method. That is, for example, a heated aluminum alloy billet 1 loaded in the container 11 of the extrusion device 10 is pressurized in the extrusion direction E with the stem 17 to thereby make the material of the billet 1 pass through the forming gap 15 of the extrusion die 12. With this, an aluminum alloy extruded tube 2 circular in cross-section can be obtained. The outer diameter of the extruded tube 2 is, for example, 20 to 50 mm, and the thickness of the extruded tube 2 is, for example, 1.0 to 2.0 mm. The specifically preferred extrusion process conditions to be applied to the extrusion process are a billet temperature of 400 to 550 C. and an extrusion rate of 15 to 60 m/min.

(8) As shown in FIG. 2, a drawing device 20 used to draw the extruded tube 2 is not specifically limited, and is a known device. That is, this drawing device 20 includes a drawing die 21, a pulling portion 23, etc. The drawing die includes a die hole 22 to reduce the diameter of the extruded tube 2. The pulling portion 23 includes a chuck portion 23a.

(9) The method of drawing the extruded tube 2 using the drawing device 20 is not specifically limited, and cold or warm drawing is performed according to a known method. That is, for example, the front end portion of the extruded tube 2 passed through the die hole 22 of the drawing die 21 of the drawing device 20 is chucked with the chuck portion 23a of the pulling portion 23, and then the extruded tube 2 is pulled in the drawing direction D with the pulling portion 23 to draw the extruded tube 2 from the die hole 22. With this, a drawn tube 3 as a non-machined tube can be obtained. The thickness of the drawn tube 3 is, for example, 0.5 to 1.5 mm. The especially preferred drawing process conditions to be applied to the drawing process are a drawing rate of 10 to 70 m/min and a diameter reduction rate of the outer diameter of the extruded tube 2 of 20 to 50%. In this drawing process, the drawing can be performed using a drawing plug (not illustrated) disposed in the hollow portion of the extruded tube 2 to process the inner surface of the extruded tube 2.

(10) Next, the drawn tube 3 is cut into a piece having a length of a photoconductor drum substrate, the end portion of the cut piece is chamfered, the cut piece is cleaned, and dimensional and appearance inspections are performed. Thus, a desired photoconductor drum substrate is obtained.

(11) When obtaining an ironed tube by ironing the extruded tube 2, using a known ironing device (not illustrated), an extruded tube is ironed under normal processing conditions. With this, an ironed tube is obtained.

(12) Next, the ironed tube is cut into a piece having a length of a photoconductor drum substrate, the end portion of the cut piece is chamfered, the cut piece is cleaned, and dimensional and appearance inspections are performed. Thus, a desired photoconductor drum substrate is obtained.

(13) In FIGS. 1 and 2, the billet 1, the extruded tube 2, and the drawn tube 3 are shown by dot-hatching to easily distinguish them from other members.

(14) Next, functions of each element constituting the composition of the aluminum alloy of this embodiment will be explained.

(15) <Si (Silicon)>

(16) Si enhances castability and also contributes to improvement of strength. The effect is assuredly exerted when the Si content is 0.03 mass % or more. On the other hand, when the Si content exceeds 0.6 mass %, rough crystallized products are formed in the aluminum alloy, which deteriorates the surface roughness of the outer surface of the extruded tube. Therefore, it is preferable that the Si content is set within a range of 0.03 to 0.6 mass %. The especially desired range of the Si content is 0.03 to 0.3 mass %.

(17) <Fe (Iron)>

(18) Fe refines crystallized products and also contributes to improvement of strength. The effect is assuredly exerted when the Fe content is 0.1 mass % or more. On the other hand, when the Fe content exceeds 0.7 mass %, rough crystallized products are formed in the aluminum alloy, which deteriorates the surface roughness of the outer surface of the extruded tube. Therefore, it is preferable that the Fe content is set within a range of 0.1 to 0.7 mass %. The especially desired range of the Fe content is 0.1 to 0.5 mass %.

(19) <Cu (Copper)>

(20) Cu contributes to improvement of strength by the solid-solution strengthening effect. The effect is assuredly exerted when the Cu content is 0.05 mass % or more. On the other hand, when the Cu content exceeds 0.20 mass %, corrosion resistance decreases. Therefore, it is preferable that the Cu content is set within a range of 0.05 to 0.20 mass %. The especially desired range of the Cu content is 0.1 to 0.20 mass %.

(21) <Mn (Manganese)>

(22) Mn forms minute intermetallic compounds together with Fe, etc., contained in the aluminum alloy to raise the recrystallization temperature and also contributes to improvement of strength. The effect is assuredly exerted when the Mn content is 1.0 mass % or more. On the other hand, when the Mn content exceeds 1.5 mass %, there is a possibility to cause deterioration of corrosion resistance. Therefore, it is preferable that the Mn content is set within a range of 1.0 to 1.5 mass %. The especially desired range of the Mn content is 1.0 to 1.3 mass %.

(23) <Mg (Magnesium)>

(24) Mg forms a thin Mg film on the bearing portions 13a and 14a of the extrusion die 12 during an extrusion process, and the die mark originating portion formed on the bearing portions 13a and 14a is coated with the thin Mg film, which contributes to prevention of forming a die mark on the outer surface of the extruded tube. The effect is assuredly exerted when the Mg content is 0.01 mass % or more. On the other hand, when the Mg content exceeds 0.1 mass %, rough crystallized products are formed in the aluminum alloy, which deteriorates the surface roughness of the outer surface of the extruded tube 2. Therefore, it is preferable that the Mg content is set within a range of 0.01 to 0.1 mass %. The upper limit of the especially desired range of the Mg content is 0.05 mass %.

(25) In this specification, the die mark originating portion refers to a portion that causes a die mark on the surface of the extruded tube 2 (outer surface and inner surface) and is formed on the bearing portions 13a and 14a of the extrusion die 12. Specifically, they are normally constituted by scratches formed on the bearing portions 13a and 14a or deposits adhered to the bearing portions.

(26) <Zn (Zinc)>

(27) Zn is an arbitrary element contained as needed, which slightly contributes to improvement of strength. When the Zn content exceeds 0.1 mass %, there is a possibility to decrease corrosion resistance. Therefore, it is preferable that the Zn content is set within a range of 0 to 0.1 mass %. The especially desired range of the Zn content is 0 to 0.05 mass %.

(28) <Ti (Titanium)>

(29) Ti is an arbitrary element contained as needed, and refines crystallized products of the billet 1 to thereby contribute to prevention of ingot cracking during a casting process. When the Ti content exceeds 0.1 mass %, there is a possibility that the extrusion workability deteriorates and large intermetallic compounds that adversely affect the workability are formed. Therefore, it is preferable that the Ti content is set within a range of 0 to 0.1 mass %. The especially desired range of the Ti content is 0.01 to 0.05 mass %.

(30) Furthermore, the aluminum alloy of this embodiment contains Cr as an arbitrary element contained as needed, and it is preferable that the Cr content is set within a range of 0 to 0.05 mass %. The reason is as follows.

(31) Cr has an effect of refining crystallized products, but when the Cr content exceeds 0.05 mass %, there is a possibility that large intermetallic compounds that adversely affect the workability are formed. Therefore, it is preferable that the Cr content is set within a range of 0 to 0.05 mass %. The upper limit of the especially preferred range of the Cr content is 0.03 mass %.

(32) In the aluminum alloy of this embodiment, since the content of each element constituting the composition is set within the predetermined range, when the aluminum alloy billet 1 is extruded, the outer surface of the extruded tube 2 can be formed into a high smooth surface. Specifically, in this aluminum alloy, since the Mg content is set within the range of 0.01 to 0.1 mass %, the outer surface of the extruded tube 2 can be assuredly formed into a high smooth surface. That is, because the Mg content is 0.01 mass % or more, the die mark originating portion formed on the bearing portions 13a and 14a of the extrusion die 12 are coated by the thin Mg film during the extrusion process. As a result, a die mark can be prevented from being formed on the outer surface of the extruded tube 2. Further, because the Mg content is 0.1 mass % or less, rough crystallized products can be prevented from being formed in the aluminum alloy during the extrusion process. Therefore, by setting the Mg content within the range of 0.01 to 0.1 mass %, the outer surface of the extruded tube 2 can be assuredly formed into a high smooth surface.

(33) By drawing or ironing the extruded tube 2, the outer surface of the drawn tube 3 or the ironed tube can be assuredly formed into a high smooth surface. Therefore, by producing a photoconductor drum substrate from the drawn tube 3 or the ironed tube, a photoconductor drum substrate having a high smooth outer surface can be obtained.

(34) Although an embodiment of the present invention was explained above, the present invention is not limited to that. The present invention allows various design-changes falling within the claimed scope of the present invention unless it deviates from the spirits of the invention.

(35) Further, in the present invention, an extruded member obtained by extruding an aluminum alloy billet is especially preferred to be used for a photoconductor drum substrate, but is not excluded from being used for other use applications. Further, the extruded member can be a tube (that is, a hollow member) as described in the aforementioned embodiment, or can be a solid member.

EXAMPLES

(36) Next, specific examples of the present invention will be described. It should, however, be noted that the present invention is not limited to these examples.

(37) TABLE-US-00001 TABLE 1 Surface Evaluation Composition (mass %) roughness of surface Si Fe Cu Mn Mg Zn Ti Al Ry (m) property Ex. 1 0.09 0.38 0.14 1.07 0.01 0.00 0.01 Balance 6.0 Ex. 2 0.12 0.50 0.16 1.30 0.01 0.05 0.02 Balance 5.8 Ex. 3 0.10 0.41 0.14 1.12 0.02 0.00 0.01 Balance 5.0 Ex. 4 0.03 0.10 0.17 1.06 0.02 0.01 0.01 Balance 4.9 Ex. 5 0.09 0.38 0.14 1.09 0.03 0.01 0.01 Balance 4.8 Ex. 6 0.30 0.70 0.15 1.20 0.03 0.00 0.02 Balance 4.7 Ex. 7 0.10 0.38 0.13 1.10 0.05 0.00 0.01 Balance 4.3 Ex. 8 0.60 0.40 0.05 1.20 0.05 0.02 0.02 Balance 4.6 Ex. 9 0.11 0.39 0.10 1.00 0.07 0.10 0.01 Balance 5.2 Ex. 10 0.12 0.42 0.17 1.14 0.08 0.01 0.02 Balance 5.1 Ex. 11 0.12 0.42 0.20 1.50 0.10 0.02 0.01 Balance 5.5 Comp. Ex. 1 0.10 0.40 0.14 1.14 0.00 0.01 0.01 Balance 6.9 X Comp. Ex. 2 0.62 0.08 0.13 0.04 0.00 0.00 0.01 Balance 7.1 X Comp. Ex. 3 0.09 0.38 0.17 1.06 0.12 0.00 0.02 Balance 6.7 X Comp. Ex. 4 0.20 0.73 0.20 1.10 0.15 0.12 0.01 Balance 7.1 X Comp. Ex. 5 0.12 0.40 0.21 1.51 0.20 0.05 0.02 Balance 8.6 X

(38) Aluminum alloy billets having the compositions as shown in Table 1 were extruded to thereby produce extruded tubes for photoconductor drum substrates. The outer diameter of the extruded tube was 32 mm, and the thickness of the extruded tube was 1.5 mm. The extrusion process conditions applied to the extrusion process were a billet temperature of 500 C. and an extrusion rate of 30 m/min.

(39) Then, the surface roughness Ry of the outer surface of the extruded tube was measured according to JIS B0601-1994 to evaluate the surface properties of the outer surface. The results are shown in Table 1. In the column of surface property in Table 1, each symbol means as follows. The surface roughness Ry denotes a maximum height.

(40) : Ry is 0 m or more, but 5 m or less

(41) : Ry exceeds 5 m, but is 6 m or less

(42) x: Ry exceeds 6 m

(43) As it can be understood from Table 1, in Examples 1 to 11, extruded tubes having high smooth outer surfaces were obtained.

(44) Therefore, by drawing or ironing the extruded tubes obtained in Examples 1 to 11, drawn tubes or ironed tubes having high smooth outer surfaces can be obtained, which in turn can obtain photoconductor drum substrates having high smooth outer surfaces can be obtained.

(45) The present invention claims priority to Japanese Patent Application No. 2011-147331 filed on Jul. 1, 2011, the entire disclosure of which is incorporated herein by reference in its entirety.

(46) The terms and descriptions used herein are used only for explanatory purposes and the present invention is not limited to them. The present invention allows various design-changes falling within the claimed scope of the present invention unless it deviates from the spirits of the invention.

(47) While the present invention may be embodied in many different forms, a number of illustrative embodiments are described herein with the understanding that the present disclosure is to be considered as providing examples of the principles of the invention and such examples are not intended to limit the invention to preferred embodiments described herein and/or illustrated herein.

(48) While illustrative embodiments of the invention have been described herein, the present invention is not limited to the various preferred embodiments described herein, but includes any and all embodiments having equivalent elements, modifications, omissions, combinations (e.g., of aspects across various embodiments), adaptations and/or alterations as would be appreciated by those in the art based on the present disclosure. The limitations in the claims are to be interpreted broadly based on the language employed in the claims and not limited to examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive. For example, in the present disclosure, the term preferably is non-exclusive and means preferably, but not limited to. In this disclosure and during the prosecution of this application, means-plus-function or step-plus-function limitations will only be employed where for a specific claim limitation all of the following conditions are present in that limitation: a) means for or step for is expressly recited; b) a corresponding function is expressly recited; and c) structure, material or acts that support that structure are not recited. In this disclosure and during the prosecution of this application, the terminology present invention or invention may be used as a reference to one or more aspect within the present disclosure. The language present invention or invention should not be improperly interpreted as an identification of criticality, should not be improperly interpreted as applying across all aspects or embodiments (i.e., it should be understood that the present invention has a number of aspects and embodiments), and should not be improperly interpreted as limiting the scope of the application or claims. In this disclosure and during the prosecution of this application, the terminology embodiment can be used to describe any aspect, feature, process or step, any combination thereof, and/or any portion thereof, etc. In some examples, various embodiments may include overlapping features. In this disclosure and during the prosecution of this case, the following abbreviated terminology may be employed: e.g. which means for example; and NB which means note well.

INDUSTRIAL APPLICABILITY

(49) The present invention is applicable to an aluminum alloy, a production method of an aluminum alloy extruded member, a production method of a photoconductor drum substrate, an aluminum alloy extruded member, and a photoconductor drum substrate.

DESCRIPTION OF THE REFERENCE NUMERALS

(50) 1: aluminum alloy billet 2: aluminum alloy extruded tube (aluminum alloy extruded member)