JP2000119784A - Aluminum alloy material excellent in high temperature creep characteristic and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the bending resistance of an alloy material in use under heating in the case of being applied to a heat roll of a copying machine or the like by composing it of an extruded material of an Al alloy contg. a specified amt. of Mn and controlling its electrical conductivity to the value equal to or below the specified one. SOLUTION: This Al alloy material contains, by weight, 0.5 to l.5% Mn, and the balance Al with impurities. Then, its electrical conductivity is controlled to <=37% IACS. The alloy material is produced by making a billet by an ordinary continuous casting system, thereafter, without executing homogenizing treatment, or executing rapid cooling after the homogenizing treatment, again heating it and executing hot extrusion working. In this way, the content of Mn solid solution in the matrix is controlled and the precipitation and dispersion of Al-Mn compds. are controlled to improve its creep characteristics at a high temp. For forming it into the stock for a heat roll, the material is subjected to port hole extrusion to form into the shape of a pipe, and, after that, for obtaining dimensional precision, preferably, cold drawing is executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum alloy material having an excellent high-temperature creep characteristic and having an excellent high-temperature creep characteristic, and particularly suitable for a heat roll used for fixing toner in a copying machine. It relates to the manufacturing method.

[0002]

2. Description of the Related Art Heat rolls used in copiers and the like are used in a temperature range of 150 to 250 ° C., and therefore are lightweight, non-magnetic, and excellent in heat conductivity as heat roll materials. At the same time, heat-resistant properties are required, and conventionally, 5000- or 6000-based aluminum alloy materials having relatively high high-temperature strength have been used.

However, these aluminum alloy materials have relatively good static strength at high temperatures, but have insufficient creep characteristics at high temperatures. When repeated stress is applied due to paper passage, there is a problem that the sheet is liable to bend and to cause defective fixing of the toner.

In order to solve the above-mentioned problems, the present applicant has previously made an aluminum alloy material for heat rolls having excellent high-temperature creep characteristics and improved bend resistance during heating, which is important in copying machines. Suggested. (Japanese Patent Laid-Open No. 9
No. -170039)

[0005]

SUMMARY OF THE INVENTION The present invention has been proposed in order to further improve the high-temperature creep characteristics and to obtain an aluminum alloy material suitable as a heat roll that can withstand long-term use even in severe use environments. It was made as a result of repeated experiments and studies on the relationship between the alloy composition and the properties of the matrix and the high-temperature creep properties, especially on the basis of the aluminum alloy that was obtained.The purpose was to excel in the high-temperature creep properties, It is an object of the present invention to provide an aluminum alloy material having improved bending resistance during heating when applied to a heat roll of a copying machine or the like, and a method for manufacturing the same.

[0006]

In order to achieve the above object, the present invention provides an aluminum alloy material having excellent high-temperature creep characteristics, which contains 0.5 to 1.5% of Mn, and the balance of aluminum alloy and impurities. An extruded material,
A first feature is that the conductivity is 37% IACS or less, and the cold-drawn material is an aluminum alloy containing Mn: 0.5 to 1.5%, the balance being Al and impurities, and having a conductivity of 37% IACS. The following is a second feature.

[0007] Further, the above-mentioned component further contains Mg: 2.0% or less, further contains Cu: 1.5% or less in addition to Mg, Si: 0.5% or less, and Zn: 0.5% or less. Ni: 2.0% or less; Fe: 1.0% or less; and Cr: 0.3% or less, Zr: 0.3% or less, V: 0.1
% Or less, Ti: 0.3% or less, and B: 0.08% or less.
Fifth, sixth and seventh features.

According to the method of the present invention for producing an aluminum alloy material having excellent high-temperature creep properties, an aluminum alloy ingot having the above composition is quenched without or after homogenization, and then subjected to hot extrusion. This is a first feature, and the second feature is that cold drawing is further performed after extrusion.

The significance of the alloy components in the present invention and the reasons for limiting them will be described. Mn is dissolved in a matrix or an Al-Mn compound is finely precipitated in the matrix to improve the strength of the alloy material. And improve the high temperature creep properties. The preferred content range is 0.5 to 1.5%. If the content is less than 0.5%, the effect is small, and if the content exceeds 1.5%, the extrudability decreases.
A more preferred content range of Mn is 0.7 to 1.3%.

[0010] Mg functions as a solid solution in the matrix to improve the strength of the alloy material. The preferred content range is
If it is 2.0% or less, and if it exceeds 2.0%, the extrudability will decrease and porthole extrusion tends to be difficult. The more preferred content of Mg is in the range of 0.9% or less.

Cu is Al-Cu-Mg in the presence of Mg.
It has the effect of precipitating the system compound and improving the creep properties especially at high temperatures. The preferred content is 1.5% or less,
A more preferred content is in the range of 0.1-1.5%,
%, The extrudability decreases. The more preferable content range of Cu is 0.5 to 1.0%.

Si coexists with Mg to form Mg.
Precipitating ₂ Si, it has a function of improving the strength of the alloy. A preferable content range is 0.5% or less. If the content exceeds 0.5%, coarse Mg ₂ Si is precipitated by holding at a high temperature, and the strength and the high-temperature creep characteristics are reduced.

[0013] Zn coexists with Mg to form MgZ.
Precipitates n ₂ and other compounds to improve the strength of the alloy material. The preferred content is in the range of 0.5% or less and 0.1%.
If it exceeds 5%, the strength and creep properties at high temperatures are reduced.

[0014] Ni and Fe are elements that contribute to improving the strength of the alloy, and the preferred content ranges are Ni: 2.0% or less and Fe: 1.0% or less. If the content exceeds the respective upper limits, coarse crystallized substances and precipitates are generated together with other coexisting elements, and the various properties of the alloy material are deteriorated. Ni and F
The more preferred content of e is in the range of 0.01 to 0.5% Ni: 0.01 to 0.5% Fe.

Cr, Zr, V, Ti and B contribute to the refinement of recrystallized grains, and in the crystal structure formed by extrusion, (crystal length in the extrusion direction / crystal in the direction perpendicular to the extrusion direction) Element that improves the high-temperature creep characteristics by reducing the ratio of (length), and the effect can be obtained by including one or more of these elements. The preferred content ranges are respectively Cr: 0.3% or less, Zr: 0.3% or less, V: 0.1% or less, Ti: 0.3% or less, and B: 0.08% or less. And reduces the strength and creep properties of the alloy.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The aluminum alloy material of the present invention
After ingot into billet according to normal continuous casting method,
It is manufactured by performing hot extrusion without performing homogenization processing, or manufactured by quenching after homogenization processing, heating again, and performing hot extrusion processing. In the case of performing the homogenization treatment, the mixture is preferably subjected to a heat treatment at a temperature of preferably 550 to 660 ° C., preferably for one hour or more, and then quenched by a means such as water cooling.
Hot extrusion is performed by heating to a temperature of ° C. In order to obtain a material for a heat roll, after performing porthole extrusion and processing into a pipe shape, cold drawing is performed to obtain dimensional accuracy.

The present invention is to improve the creep characteristics at high temperatures by controlling the amount of solid solution of Mn in the matrix and controlling the precipitation and dispersion of the Al-Mn compound. Conductivity 37% IACS
This is achieved by adjusting the following. Conductivity 37%
When it exceeds IACS, the solid solution amount of Mn in the matrix is small, and the high-temperature creep characteristics deteriorate.

[0018]

EXAMPLE 1 A billet (diameter: 90 mm) of an aluminum alloy having the composition shown in Table 1 was cast by continuous casting, and homogenized under the conditions shown in Table 2, and then a porthole die was used. At a temperature of 400 ° C., hot extrusion is performed at an extrusion speed applied in ordinary extrusion molding, and a diameter of 20 m
A cylindrical extruded tube having a thickness of 3 mm and a thickness of 3 mm and a round bar were manufactured, and the conductivity was measured to evaluate the extrudability.

Further, the extruded rod is heated to a temperature of 200 ° C. at 80 M
A creep test in which a constant load of Pa was applied and held for 100 hours was performed to investigate high-temperature creep characteristics. 20mm diameter
Was subjected to cold drawing to a diameter of 16 mm (workability: 36%), and a similar creep test was performed to evaluate the creep characteristics. Table 2 shows the results. In Table 2, the evaluation of the extrudability and the evaluation of the creep characteristics are as follows.

Extrusion: Investigation was made on whether or not porthole extrusion was possible, and ポ ー ト indicates that porthole extrusion was possible and X indicates that porthole extrusion was not possible. Creep characteristics: 破 断 indicates that no rupture occurred in the creep test, and × indicates that rupture occurred.

As can be seen from Table 2, all of the test materials according to the present invention can be extruded through a porthole,
It shows excellent high-temperature creep characteristics without breaking in a creep test at 100 ° C. for 100 hours.

[0022]

[Table 1]

[0023]

[Table 2] << Table Note >> Homogenization treatment A: No homogenization treatment B: 8h at 630 ° C → water cooling

Comparative Example 1 A billet (diameter: 90 mm) of an aluminum alloy having the composition shown in Table 3 was cast by continuous casting, homogenized under the conditions shown in Table 4, and then subjected to a 400 hole mill using a porthole die. At a temperature of 0 ° C., hot extrusion is performed at an extrusion speed applied in ordinary extrusion molding, and a diameter of 20 m
A cylindrical extruded tube having a thickness of 3 mm and a thickness of 3 mm and a round bar were manufactured, and the conductivity was measured to evaluate the extrudability.

Further, as in Example 1, the extruded rod was
A creep test in which a constant load of 80 MPa was applied at a temperature of ° C. and held for 100 hours was performed to investigate high-temperature creep characteristics. An extruded round bar having a diameter of 20 mm was cold-drawn to a diameter of 16 mm (working rate: 36%), and a similar creep test was performed on these to evaluate creep characteristics. Table 4 shows the results. In Tables 3 and 4, those outside the conditions of the present invention are underlined.

[0026]

[Table 3]

[0027]

[Table 4] << Table Note >> Homogenization treatment A: No homogenization treatment B: 8h at 630 ° C → water cooling C: 10h at 600 ° C → air cooling D: 10h at 500 ° C → furnace cooling

As shown in Table 4, test materials Nos. 22 to 33
Has a high electrical conductivity and a small amount of Mn solid solution in the matrix, and thus has a poor high-temperature creep property.
Test material No. 34 and No. 34. In No. 38, since the content of Mn was large, the extrudability was reduced and porthole extrusion could not be performed. Test material No. 36 and No. 36. No. 40 has a large amount of Mg. 37 and no. In No. 41, since the amount of Cu was large, the extrudability was reduced, and porthole extrusion could not be performed.

Test material No. No. 35 and No. 35. 39 is M
Since the content of n is small, Al-
Precipitation and dispersion of Mn-based compounds are reduced, and as a result,
Poor high temperature creep strength properties.

[0030]

According to the present invention, high-temperature creep characteristics are excellent, and when applied to a heat roll, the bending resistance during use by heating is improved, and the extrudability is good, so that high-speed porthole extrusion can be performed. In particular, an aluminum alloy material suitable as a material for a heat roll and a method for producing the same are provided.

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Claims (9)

[Claims] 1. Mn: 0.5 to 1.5% (% by weight, hereinafter the same)
An aluminum alloy extruded material comprising aluminum and the balance of Al and impurities, having an electrical conductivity of 37% IACS or less and having excellent high-temperature creep properties. 2. A cold drawn material of an aluminum alloy containing Mn: 0.5 to 1.5%, the balance being Al and impurities, having an electrical conductivity of 37% IACS or less. Excellent aluminum alloy material. 3. Mg: 2.0% or less (excluding 0%,
The aluminum alloy material having excellent high-temperature creep properties according to claim 1 or 2, wherein the same applies hereinafter. 4. The aluminum alloy material having excellent high-temperature creep properties according to claim 3, further comprising Cu: 1.5% or less. 5. The aluminum alloy material having excellent high-temperature creep properties according to claim 1, further comprising one or two of Si: 0.5% or less and Zn: 0.5% or less. 6. The aluminum alloy material having excellent high-temperature creep characteristics according to claim 1, further comprising one or two of Ni: 2.0% or less and Fe: 1.0% or less. 7. The composition further comprises one or more of Cr: 0.3% or less, Zr: 0.3% or less, V: 0.1% or less, Ti: 0.3% or less, and B: 0.08% or less. The aluminum alloy material having excellent high-temperature creep properties according to claim 1. 8. A high-temperature creep characteristic wherein the aluminum alloy ingot having the composition according to claim 1 is subjected to hot extrusion without or after homogenization. Method of manufacturing aluminum alloy material with excellent quality. 9. The method for producing an aluminum alloy material having excellent high-temperature creep characteristics according to claim 8, wherein cold drawing is further performed after the hot extrusion.