JPH0328342A - Aluminum alloy having excellent extrudability and cold workability - Google Patents

Abstract

PURPOSE:To improve the extrudability, cold formability, machinability and heat resistance in the Al alloy by specifying the contents of Fe, Cu, Mn, Mg and Zr without substantially incorporating Ni and Si thereto. CONSTITUTION:The compsn. of the alloy is formed from, by weight, 0.2 to 0.6% Fe, 0.15 to 0.6% Cu, 0.6 to 1.5% Mn, 0.7 to 1.3% Mg, 0.05 to 0.2% Zr and the balance Al with inevitable impurities. The Al alloy is excellent in heat resistance, extrudability, reduction workability and machinability. The alloy is suitable as the material for products formed into a tube shape and used as a heating roller for a copying machine, etc.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides extrudability and cold workability suitable for use in the manufacture of products molded into tubular shapes, particularly heat rollers for copying machines, etc. Regarding aluminum alloys with excellent properties.

[Conventional Technology The constituent materials of heat rollers for copiers are required to be lightweight and non-magnetic due to their usage, and are required to have excellent machinability in manufacturing.

Also, the temperature of the heat roller during use is 180 to 20℃.
Since the temperature reaches 0°C, it is necessary to have high heat resistance and high temperature strength. Furthermore, since the heat roller is tubular, the material for the heat roller must have excellent extrudability and cold workability such as cold forgeability and drawability in order to be formed into a tubular shape.

Conventionally, this heat roller for copying machines conforms to JIS 8063,
It is molded from an aluminum alloy such as GO6l or 5052. In addition, JP-A-63-1 discloses improved heat resistance or surface smoothness of these alloys.
1840. 83-11842, G3-179041
The proposed method is as disclosed in No.

[Problems to be Solved by the Invention] However, the above-described conventional aluminum alloy for heat rollers has the following drawbacks. First, JIS S
Ol? 3 alloy and JIS 8081 alloy have excellent extrudability and cold formability, but are inferior in heat resistance.

Therefore, if a thin-walled Nojito roller is manufactured using these alloys, the roller will be deformed during use at high temperatures.

Therefore, with the above-mentioned types of aluminum alloys, there is a problem that the rollers must be formed into thick rollers and cannot be made thinner and lighter.

Further, although the JIS 5052 alloy has relatively excellent heat resistance strength, it has poor extrudability. For this reason, extrusion processing using a welding type die called a porthole die is not possible, making multi-hole extrusion processing and thin-wall extrusion processing difficult. Further, since this alloy undergoes large work hardening during drawing, it is necessary to set a large number of annealing cycles. Therefore, when a heat roller is manufactured using this alloy, there is a problem in that the manufacturing cost is high.

Furthermore, after rollers such as heat rollers are formed by extrusion processing and drawing processing, finish cutting is performed in the final process, but JIS 5052 alloy, JIS 8081 alloy, and JIS 6083 alloy all have insufficient machinability. Therefore, it is difficult to obtain high-quality heat roller products.

Furthermore, the aluminum alloy described in the above-mentioned publication has N
Since it contains a large amount of i or Si, it has the disadvantage of insufficient extrudability.

The present invention has been made in view of such problems, and includes:
Our objective is to provide an aluminum alloy with excellent extrudability, cold-opening formability, machinability, and heat resistance strength, and which is suitable for use in parts formed into tubular shapes. purpose.

[Means for Solving the Problems] The aluminum alloy having excellent extrudability and cold workability according to the present invention has Fe +0.1 of 0.2 to 0.6% by weight.
5 to 0.8 wt.% Cu, 0.8 to 1.5 wt.% Mn*0. 7 to 1.3% by weight Mg and 0.
It is characterized by containing 0.05 to 0.2% by weight of Zr, with the remainder consisting of aluminum and unavoidable impurities.

[Function] The present invention substantially does not contain Ni or St, and contains F e +
By appropriately setting the content of each component of C u + M n *M g and Zr, the extrudability, cold-open formability, machinability, and heat-resistant strength of the aluminum alloy are improved.

Next, the reason for adding each component of the aluminum alloy according to the present invention and the reason for limiting the composition will be explained.

Like Mn, LtFe has the effect of improving machinability and strength. Further, Fe improves the drawability and cold formability of the aluminum alloy. When the Fe content is less than 0.2% by weight, these effects are insufficient, and 0.66% by weight
If it exceeds the above, bulky products will be produced, which will cause a decrease in strength and formability.

Therefore, the Fe content should be 0.2 to 0.6% by weight.

Cu has the effect of improving the strength of aluminum alloys. If the Cu content is 0.15% by weight and no grooves are formed, a sufficient strength improvement effect cannot be obtained. Further, as the Cu content increases, the strength increases, but the extrudability decreases. Therefore, if the Cu content exceeds 0.6% by weight, extrusion processing using a porthole die becomes difficult, making it difficult to extrude a welded type tube. Therefore, the Cu content is set to 0.15 to 0'% by weight.

MJ-Mn contributes to improving the strength and cold-opening formability of the aluminum alloy. If the Mn content is 0'' wt% and no grooves are formed, these effects are insufficient, strength equivalent to that of JIS 5052 alloy cannot be obtained, and seizure is likely to occur during cold-open forming. Furthermore, if the Mn content exceeds 1.5% by weight, there is a possibility that giant crystallized substances will be generated, and the effect of improving strength and cold formability will be saturated. Therefore, the Mn content is set to 0.6 to 1.5% by weight.

MJL Mg is the most important element in maintaining strength. Mg
If the content is 0.7% by weight, it is impossible to maintain strength equal to or higher than that of JIS5052 alloy. Although the strength improves as the Mg content increases, if the Mg content exceeds 1.3% by weight, extrusion processing using a porthole die becomes difficult.

Therefore, the Mg content is set to 0.7 to 163% by weight.

Ego Zr is an important additive element of the aluminum alloy according to the present invention, and has the effect of improving strength by making crystal grains finer. In order to obtain such a strength-improving effect, the zr content needs to be 0.05% by weight or more. On the other hand, even if Zr is contained in an amount exceeding 0.2% by weight, the effect is saturated. Therefore, the Zr content is 0.
05 to 0.2% by weight.

In addition to the above ingredients, in order to refine the grains of the ingot,
0.005 to 0.1% by weight of Ti may be contained.

[Example] Next, examples of the present invention will be described.

First, each aluminum alloy having the composition shown in Table 1 below was melted by a conventional method, and a billet having an outer diameter of 200 m was cast.

Note that Examples 1 to 4 fall within the composition range defined by the present invention, and Comparative Examples 1 to 7 fall outside of this composition range. In particular, Comparative Example 5 is JIS 6063 alloy, Comparative Example 6 is JIS 6081 alloy, and Comparative Example 7 is JIS 50 alloy.
52 alloy. The obtained billet ingot was subjected to homogenization treatment under predetermined conditions and cut into lengths of 400 mm. Next, this billet was hot extruded using a porthole die at an extrusion temperature of 500°C, and the outer diameter was reduced to 35.
．． , two tubes with a wall thickness of 31 mm were manufactured. Furthermore, by subjecting this extruded tube to a drawing process, the outer diameter becomes 34mm. ．． A final raw tube with a wall thickness of 2wit was manufactured.

In the manufacturing process of the raw pipes according to Examples 1 to 4 and Comparative Examples 1 to 7 thus obtained, their extrudability and drawability were evaluated. In addition, each of the raw pipes after manufacture was cut, and the quality of the cutting performance was compared and evaluated based on the state of division of the chips.

Table 1 These results are summarized in Table 2 below. Note that the yield strength is the tensile strength after heating the raw pipe to 400° C. for 1 hour, and indicates the resistance to deformation at high temperatures. Extrudability is ○ if extrusion was possible even at a high extrusion speed of 10 m/min in the extrusion process using a porthole die, Δ if extrusion was possible only at a low speed of 1 m/min. Cases in which extrusion was not possible are indicated by x. The drawing property was evaluated by the degree of seizure during the drawing process, and 0 indicates no seizure, Δ indicates slight seizure, and × indicates large seizure. Moreover, the machinability is shown as 0 when the chips of the raw pipe are finely divided, Δ when they are slightly connected, and × when they are continuous.

Table 2 As is clear from this Table 2, Comparative Examples 1, 2, 3, 5
and No. 6 have low yield strength and poor heat resistance strength, and often have insufficient extrudability, drawability, and machinability. Furthermore, Comparative Examples 4 and 7 have drawbacks in extrudability, drawability, and cuttability.

On the other hand, the aluminum alloys according to Examples 4 to 4 of the present invention exhibit yield strength equal to or higher than that of the conventional JIS 5052 alloy (Comparative Example 7), which has excellent heat resistance strength. In addition, the aluminum alloys of Examples 1 to 4 meet the JIS G standards, which are said to have excellent extrudability and drawability.
It shows extrudability and drawability equivalent to or better than O[i3 alloy (Comparative Example 5) and JIS 60ft1 alloy (Comparative Example 8). Furthermore, the machinability of each of the example alloys is extremely superior to that of the comparative example alloys.

Therefore, the aluminum alloy according to this example is extremely excellent in both productivity and heat resistance properties.

Note that the method of manufacturing a tube such as a heat roller using the aluminum alloy of the present invention is not limited to the case of drawing after extrusion as in the above-mentioned embodiments, but also cold forging of a cast bar, for example. It can also be formed into a tube shape.

[Effects of the Invention] As explained above, according to the present invention, not only the heat resistance strength is excellent, but also the extrudability, drawing property and cutting property are excellent.
An aluminum alloy that is excellent in both productivity and properties such as strength and heat resistance can be obtained. Therefore, if this aluminum alloy is used as a material for products that are formed into tubular shapes, such as heat rollers for copying machines, products with high heat resistance and easy thinning can be easily manufactured through a simple process. can be manufactured.

Claims (1)

[Claims] (1) 0.2-0.6% by weight of Fe, 0.15-0
．． 6% by weight Cu, 0.6-1.5% by weight Mn, 0
．． Aluminum with excellent extrudability and cold workability, characterized by containing 7 to 1.3% by weight of Mg and 0.05 to 0.2% by weight of Zr, with the remainder consisting of aluminum and unavoidable impurities. alloy.