JP2000313930A - Aerial wire compression joint sleeve made of aluminum alloy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the manufacturability, compressibility at connection, and connection reliability of a sleeve by incorporating specific amounts of Zr, Fe, Si, and Ti and/or V into an Al alloy. SOLUTION: The aerial wire compression joint sleeve made of Al alloy has a composition consisting of, by weight, 0.01-0.4% Zr, 0.05-0.2% Fe, 0.05-0.2% Si, 0.003-0.05%, in total, of at least either of Ti and V, and the balance Al with inevitable impurities. This sleeve is subjected to aging treatment at about 350-420 deg.C for about 4-72 hr or subjected to solution heat treatment at about 515-550 deg.C and then to aging treatment at about 150-250 deg.C for about 4-36 hr. At this time, Zr in the composition is allowed to enter into solid solution in an Al matrix to impede the motion of dislocation at heating and suppress stress relaxation; Fe is an inevitable impurity element contained in the Al ground metal and is allowed to enter into solid solution or precipitate to contribute to the improvement of heat resistance although its quantity is extremely small; and Si promotes the precipitation of an Al-Fe compound to improve electric conductivity and hot workability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention compresses and connects a stranded aluminum wire (an overhead wire) such as a straight sleeve, an end clamp, a jumper sleeve, each of T, Y, and L type branch sleeves, a repair sleeve, and a compression terminal. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum alloy overhead wire compression connection pipe having improved workability, compression workability during connection, and stress relaxation resistance.

[0002]

2. Description of the Related Art Conventionally, an aluminum alloy overhead wire compression connection pipe is made of pure aluminum JI when conductivity is given priority.
When SA1070 alloy is used and strength is given priority, JIS 6101 alloy, JISA6061 alloy, JIS
Age-hardened aluminum alloys such as A6063 alloy (Al-Mg-Si alloy) have been used, but since these alloys have large stress relaxation, the contact resistance between the compression connection pipe and the aluminum stranded wire due to heat generation during power transmission is high. As a result, abnormal heat generation occurs, and as a result, there is a possibility that the reinforcing steel wire of the aluminum stranded wire is disconnected or the aluminum stranded wire is dropped from the connection pipe.

[0003]

SUMMARY OF THE INVENTION
A composite material in which ceramics are dispersed in a base material has been proposed as a material that is difficult to relieve stress (Japanese Patent Application No. 6-338232). However, this composite material has poor workability and cracks when compressed (compression molding). And the production cost is high. In view of such circumstances, the present inventors have developed a mechanical and electrical method of a metal material necessary for satisfying various properties such as manufacturing workability to a compression connection pipe, compression workability at the time of connection, and stress relaxation resistance. After examining the properties, etc., the tensile strength is 145 N / mm ² or more,
0.2% proof stress 70N / mm ² or more, elongation 5% or more, 24
90% or more of residual strength when heated at 0 ° C for 30 minutes, conductivity 5
It was found that the above properties were satisfied when the IACS was 8% IACS or more. Further, the alloy composition, heat treatment conditions, and the like were extensively studied, and the present invention was completed. An object of the present invention is to provide an inexpensive aluminum alloy overhead wire compression connection pipe that is excellent in manufacturing workability, compression workability during connection, connection reliability, and is inexpensive.

[0004]

According to the first aspect of the present invention,
0.01 to 0.4 wt% of Zr, 0.05 to 0.2 of Fe
wt%, 0.05-0.2wt% of Si.
i, V at least one selected from the group consisting of 0.0
This is an aluminum alloy overhead wire compression connection pipe characterized by containing 0.3 to 0.05% by weight, with the balance being Al and unavoidable impurities.

[0005] According to the second aspect of the present invention, Zr is set to 0.01 to
0.4 wt%, 0.05-0.7 wt% of Fe, and 0.1% of Si.
0.05 to 0.6 wt%, and at least one selected from the group consisting of Be, Sr, and Mg is 0.001 to 0.1 wt% in total.
At least one selected from the group consisting of Ti and V
The seed contains 0.003-0.05wt% in total, and the balance is A
and an aluminum alloy overhead wire compression connection pipe comprising unavoidable impurities, said connection pipe being at 350-420 ° C.
This is an aluminum alloy overhead wire compression connection pipe that has been subjected to aging treatment for up to 72 hours.

[0006] The invention according to claim 3 is that the Zr is 0.01 to
0.4 wt%, 0.2-0.7 wt% Fe, 0.2 Si
-0.6 wt%, 0.35-1.2 wt% of Mg, 0.05-0.4 wt% of Cu, and at least one selected from the group consisting of Ti and V in a total amount of 0.003-0. .05
An aluminum alloy overhead wire compression connection pipe containing wt%, the balance being Al and unavoidable impurities, wherein the connection pipe is solution-treated at 515-550 ° C.
This is an aluminum alloy overhead wire compression connection pipe that has been aged at 50 ° C. for 4 to 36 hours.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The first aspect of the present invention relates to a method for producing Zr, F
An aluminum alloy overhead wire compression connection pipe containing a predetermined amount of at least one selected from the group consisting of e, Si, Ti, and V, respectively, comprising a die casting method, a machining method, a hot working method,
It is processed by a processing method or the like in which these are combined, and the connection pipe after processing does not need to be subjected to a solution treatment or an aging treatment.

In the first aspect of the present invention, Zr is Al
It dissolves in the matrix to prevent the movement of dislocations during heating, thereby suppressing stress relaxation. The content is 0.01-0.4wt
The reason for specifying the percentage is that if the content is less than 0.01 wt%, the effect cannot be sufficiently obtained, and if it exceeds 0.4 wt%, casting cracks and cracks due to compression processing at the time of connection tend to occur.

[0009] Fe is an unavoidable impurity element contained in aluminum ingots, and contributes to improvement in heat resistance by solid solution or precipitation even in a trace amount. The reason for defining the content to be 0.05 to 0.2 wt% is that if it is less than 0.05 wt%, it is uneconomical because it is necessary to use a high-purity metal, and if it exceeds 0.2 wt%, it will be used as a connecting pipe. This is because the required conductivity cannot be obtained.

[0010] Si promotes the precipitation of the Al-Fe-based compound to improve the conductivity and the hot workability. The reason for defining the content to be 0.05 to 0.2 wt% is as follows.
If the content is less than wt%, the effect cannot be sufficiently obtained, and if the content is more than 0.2 wt%, the conductivity required as a connection pipe cannot be obtained.

[0011] Ti and V refine the cast structure and improve the processability of the connection tube and the compression process during connection. The reason that the content is specified as 0.003 to 0.05 wt% in total is that if the content is less than 0.003 wt%, the effect cannot be sufficiently obtained, and if the content exceeds 0.05 wt%, the conductivity is significantly reduced. is there.

According to a second aspect of the present invention, there is provided a compression connecting pipe comprising Zr, F
e, Si each containing a predetermined amount, Be, Sr, Mg,
An aluminum alloy overhead wire compression connecting pipe containing a predetermined amount of at least one selected from the group consisting of Ti and V and further containing a predetermined amount of at least one selected from the group of Ti and V. Process, hot working, or a combination of these processes.The processed connecting pipe is subjected to an aging treatment to precipitate solid-solution elements, and has properties such as strength, conductivity, and stress relaxation resistance. It is enhanced.

In the present invention, the aging treatment is performed in a range of 350 to 42.
The reason why the heating is performed at 0 ° C. for 4 to 72 hours is as follows.
If the temperature is lower than 4 ° C or lower than 4 hours, the effect cannot be sufficiently obtained.
If the temperature exceeds 420 ° C., the precipitates become coarse and improvement in heat resistance cannot be expected, and even if aging is performed for more than 72 hours, the effect is saturated and uneconomical.

In the present invention, Zr partially precipitates in a solid solution form by aging treatment to improve heat resistance.
Some also dissolve in the Al matrix to prevent dislocation movement during heating, thereby suppressing stress relaxation. The content is set to 0.
The reason for defining the content to be 0.01 to 0.4 wt% is that if the content is less than 0.01 wt%, the effect cannot be sufficiently obtained, and if the content exceeds 0.4 wt%, cracks are easily generated by casting cracking and compression processing at the time of connection. It is.

Fe is an unavoidable impurity contained in aluminum ingot, and even in a very small amount, solid solution or precipitation improves heat resistance. The reason for defining the content to be 0.05 to 0.7 wt% is that if the content is less than 0.05 wt%, it is uneconomical due to the necessity of using a high-purity metal, and if it exceeds 0.7 wt%, aging treatment is performed.
This is because the conductivity required for the connection pipe cannot be obtained even if the precipitate is deposited.

Si promotes the precipitation of the Al-Fe compound to improve the electrical conductivity and hot workability. The reason that the content is defined as 0.05 to 0.6 wt% is 0.05 wt%
If it is less than 0.6 wt%, the effect cannot be sufficiently obtained, and if it exceeds 0.6 wt%, even if aging treatment is performed to precipitate Si, the conductivity required for a connection pipe cannot be obtained.

In the present invention, at least one selected from the group consisting of Be, Sr, and Mg promotes precipitation of an Al-Zr compound during aging treatment. The total content is 0.001
The reason for defining the content to be 0.1 wt% is that if the content is less than 0.001 wt%, the effect cannot be sufficiently obtained, and if the content exceeds 0.1 wt%, the conductivity required as a connection pipe cannot be obtained. T
At least one selected from the group consisting of i and V refines the cast structure and improves the formability of the connecting pipe. The reason for specifying the total content to be 0.003 to 0.05 wt% is as follows.
If the content is less than 0.003 wt%, the effect cannot be sufficiently obtained.
If the content exceeds 0.05 wt%, the effect is saturated and the conductivity is significantly reduced.

According to a third aspect of the present invention, Zr, Fe, S
An aluminum alloy overhead wire compression connection pipe containing a predetermined amount of at least one selected from the group consisting of i, Mg, Cu, and Ti and V, respectively, comprising a die casting method, a machining method, a hot working method, It is processed by a processing method that combines these,
The connection pipe after processing is subjected to a solution treatment and an aging treatment to precipitate a solid solution element, thereby enhancing properties such as strength, conductivity, and stress relaxation resistance.

The solution treatment is carried out at a temperature of 515 to 550 ° C. because the alloying element does not form a solid solution at a temperature lower than 515 ° C. and may locally melt at a temperature exceeding 550 ° C. The aging treatment is performed at 150-250 ° C for 4-
The reason why the heating is performed under the condition of heating for 36 hours is that if the temperature is less than 150 ° C. or less than 4 hours, the effect of improving the strength and conductivity by the aging treatment cannot be sufficiently obtained.
This is because, even if the time exceeds 6 hours, overaging occurs, the strength is reduced, and stress relaxation is likely to occur.

In the present invention, Zr forms a solid solution in the Al matrix and inhibits dislocation movement during heating, thereby suppressing stress relaxation. Further, by aging treatment after forming the connection pipe, solid solution Zr
Are partly precipitated to improve heat resistance. The reason for defining the content to be 0.01 to 0.4% by weight is as follows.
If the content is less than wt%, the effect cannot be sufficiently obtained, and if it exceeds 0.4 wt%, casting cracks and compression workability at the time of connection decrease.

Fe forms a solid solution or precipitates and contributes to improvement in strength and heat resistance. 0.2-0.7wt
The reason for specifying in% is that if it is less than 0.2 wt%, sufficient strength cannot be obtained, and if it exceeds 0.7 wt%, even if Fe is precipitated by aging treatment after solution treatment, it is necessary for the conductive pipe to be used as a connection pipe. This is because the rate cannot be obtained.

Si promotes precipitation of the Al-Fe compound to improve strength, conductivity, and hot workability. The reason for defining the content to be 0.2 to 0.6 wt% is that 0.2 wt%
%, The effect cannot be sufficiently obtained, and when it exceeds 0.6 wt%, the conductivity required as a connection pipe cannot be obtained even if Si is deposited by aging treatment after solution treatment.

Mg contributes to improvement in strength. The reason that the content is defined as 0.35 to 1.2 wt% is 0.35 wt%
If it is less than 1.2 wt%, the effect cannot be sufficiently obtained, and if it exceeds 1.2 wt%, cracks occur during quenching after solution treatment or during hot working.

Cu precipitates as a compound by the aging treatment and contributes to the improvement of the strength. The content is 0.05 to 0.1.
The reason for specifying 4 wt% is that if the content is less than 0.05 wt%, the effect cannot be sufficiently obtained, and if the content exceeds 0.4 wt%, the conductivity is significantly reduced.

[0025] Ti and V refine the casting structure and contribute to the improvement of the workability in production and the compression workability at the time of connection. Further, it promotes precipitation of the Al-Zr-based compound during the aging treatment. The reason for defining the content to be 0.003 to 0.05 wt% is that if the content is less than 0.003 wt%, the effect cannot be sufficiently obtained, and if the content exceeds 0.05 wt%, the effect is saturated. In addition, the conductivity is significantly reduced.

[0026]

The present invention will be described below in detail with reference to examples. (Example 1) An alloy having a composition specified in claim 1 of the present invention as shown in Table 1 was melted and cast into a mold, and the obtained ingot was hot forged to form a connecting pipe having the dimensions and shape shown in FIG. (Clamp tube) was manufactured.

Comparative Example 1 A connection pipe (clamp pipe) having the dimensions and shape shown in FIG. 1 was manufactured in the same manner as in Example 1 except that the comparative composition alloy of claim 1 shown in Table 1 was used.

Each of the samples produced in Example 1 and Comparative Example 1
Various test pieces are cut out from the connecting pipe to provide strength and stress relaxation resistance.
Properties and conductivity were measured. The stress relaxation resistance characteristics of the test piece
After pre-straining 5wt%, and then heated at 240 ° C for 30 minutes
Then, it is subjected to a tensile test and a 0.2% proof stress T_TwoSeeking and heating
0.2% proof stress T before₁Strength residual ratio [(T₁-T _Two)
/ T₁] Was calculated and evaluated. Strength and conductivity are determined by standard methods
It was measured. Table 2 shows the results.

[0029]

[Table 1] (Note) Unit: wt%.

[0030]

[Table 2] (Note) TS: tensile strength, YS: 0.2% proof stress.

As is evident from Table 2, No. 1
Each of 1, 2 has a tensile strength of 145 N / mm ² or more,
0.2% proof stress 70N / mm ² or more, elongation 5% or more, 24
The residual strength ratio after heating at 0 ° C. for 30 minutes satisfies 90% or more, and the conductivity is 58% IACS or more. Also, the tensile strength and the residual strength ratio were high, and the electrical conductivity and the elongation were at the same level. For this reason, Nos. 1 and 2 of the present invention examples have no problem in the manufacturing processability and the compression processability at the time of connection, and a 410 mm ² ACSR was compression-connected to the connection pipe to conduct an electric current test. However, no abnormal heat generation occurred and the connection reliability was excellent. The reason why the strength residual ratio (stress relaxation resistance) of No. 3 of the comparative example is low is that Zr is small. No. 4 of the comparative example could not be produced due to a large number of casting cracks due to a large amount of Zr. No. 5 had a lot of Fe, so N
No. 7 had a large amount of Si, and No. 8 had a large amount of Ti and V, so that the electrical conductivity decreased in all cases. In No. 6, the hot workability and the electrical conductivity were reduced due to the small amount of Si. Thus, Nos. 3, 5, 6, 7, and 8 of Comparative Examples have tensile strength, 0.2% proof stress,
Elongation, strength remaining rate, or conductivity is poor, so abnormal heat generation occurs in the current test, manufacturing processability is poor,
Or cracks occurred during the compression processing at the time of connection.

Example 2 An alloy having the composition specified in claim 2 of the present invention shown in Table 3 was melted and cast into a mold, and the obtained ingot was hot forged and processed into a straight sleeve shape. This was subjected to a heat treatment (aging treatment) under various conditions to produce a connection pipe (clamp pipe) having the dimensions and shape shown in FIG.

Comparative Example 2 A connecting pipe having the dimensions and shape shown in FIG. 1 was manufactured in the same manner as in Example 2 except that the comparative composition alloy of claim 2 shown in Table 3 was used.

Various test pieces were cut out from each of the connection tubes manufactured in Example 2 and Comparative Example 2, and the strength, stress relaxation characteristics, and conductivity were measured in the same manner as in Example 1. The results are shown in Tables 4 and 5.

[0035]

[Table 3] (Note) Unit: wt%.

[0036]

[Table 4]

[0037]

[Table 5]

As is clear from Tables 4 and 5,
No.11~14 are both tensile strength 145N / mm ² or more, 0.2% 70N / mm ² or more, elongation more than 5%,
The strength retention after heating at 240 ° C. for 30 minutes was 90% or more, and the conductivity was 58% IACS or more. No. 15 of Comparative Example
In all cases, the conductivity, tensile strength, and residual strength ratio were higher than (conventional materials corresponding to JISA1070). For this reason, all of Nos. 11 to 14 of the examples of the present invention had no problem in manufacturing workability and compression workability at the time of connection, and were subjected to an electric current test by compressing and connecting 410 mm ² ACSR to the connection pipe. No abnormal heat generation occurred and the connection reliability was excellent. Nos. 16 to 28 of the comparative examples have tensile strength, 0.2% proof stress, elongation,
Either the residual strength ratio or the electrical conductivity was inferior, which caused abnormal heat generation in the energization test, inferior manufacturing workability, or cracking in the compression processing during connection.

EXAMPLE 3 An alloy having the composition specified in claim 3 of the present invention shown in Table 6 was melted and cast into a linear sleeve-shaped mold. After solidification, the surface was blasted, and then heat-treated under various conditions. (Solution treatment → aging treatment) was performed to produce a connecting pipe having the dimensions and shape shown in FIG.

Comparative Example 3 A connecting pipe having the dimensions and shape shown in FIG. 1 was manufactured in the same manner as in Example 3 except that the comparative composition alloy of claim 3 shown in Table 6 was used.

Various test pieces were cut out from each of the connection tubes manufactured in Example 3 and Comparative Example 3, and the strength, stress relaxation characteristics, and conductivity were measured in the same manner as in Example 1. The results are shown in Tables 7 and 8.

[0042]

[Table 6] (Note) Unit: wt%.

[0043]

[Table 7]

[0044]

[Table 8] (Note) Alloy Nos. U and zz suffered casting cracks, so subsequent processing was stopped.

As is apparent from Tables 7 and 8,
No.31~34 are both tensile strength 145N / mm ² or more, 0.2% 70N / mm ² or more, elongation more than 5%,
90% or more strength residual ratio when heated at 240 ° C, conductivity 58
% IACS or more. Also, compared to No. 43 of the comparative example (conventional material equivalent to JISA6063), the No. 43 of the present invention example.
31 to 34 all had high electrical conductivity, tensile strength, and strength retention. Therefore, Nos. 31 to 34 of the present invention examples are all
There was no problem in the workability of the manufacturing process and the compression workability at the time of connection, and an electric current test was performed by compressing and connecting 410 mm ² of ACSR to the connection pipe, but no abnormal heat generation occurred and the connection reliability was excellent. . Nos. 35 to 42 and 44 to 50 of the comparative examples are inferior in tensile strength, 0.2% proof stress, elongation, strength remaining rate, or conductivity, so that abnormal heat generation occurs in the current test.
Either the manufacturing processability was poor, or cracks occurred during compression processing at the time of connection.

[0046]

As described above, the compression connection pipe of the present invention has a good balance of properties such as tensile strength, 0.2% proof stress, elongation, residual strength at 240 ° C. heating, and electrical conductivity. Therefore, it is excellent in various properties required for the compression connection pipe, such as manufacturing workability, compression moldability, and connection reliability. It is also cheaper than a composite connection pipe. Therefore, an industrially remarkable effect is achieved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an aluminum alloy overhead wire compression connection pipe.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (reference) // C22F 1/00 602 C22F 1/00 602 626 626 630 630A 630K 661 661A 682 682 691 691B 691C (72) Inventor Susumu Tomita 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. (72) Inventor Hirotaka Hashi 1-3-1, Uchisaiwaicho, Chiyoda-ku, Tokyo F-term (reference) 5E085 BB03 BB30 CC03 CC04 CC08 DD13 EE11 EE24 EE32 HH40 JJ06 JJ38 JJ46 JJ50 5G301 AA03 AA09 AA12 AA19 AA24 AB20 AD10

Claims (3)

[Claims] 1. An alloy containing 0.01 to 0.4 wt% of Zr, 0.05 to 0.2 wt% of Fe, 0.05 to 0.2 wt% of Si, and at least one selected from the group consisting of Ti and V. One type contains 0.003-0.05wt% in total, and the balance is Al
And an aluminum alloy overhead wire compression connection pipe, comprising: 2. It contains 0.01 to 0.4 wt% of Zr, 0.05 to 0.7 wt% of Fe, 0.05 to 0.6 wt% of Si, and is selected from the group consisting of Be, Sr, and Mg. At least one
Seeds in a total content of 0.001-0.1 wt%,
i, V at least one selected from the group consisting of 0.0
An aluminum alloy overhead wire compression connection pipe containing 0.3 to 0.05 wt% and the balance being Al and inevitable impurities, wherein the connection pipe has been aged at 350 to 420 ° C. for 4 to 72 hours. Aluminum alloy overhead wire compression connection pipe. 3. Zr 0.01 to 0.4 wt%, Fe 0.2 to 0.7 wt%, Si 0.2 to 0.6 wt%, Mg
0.35 to 1.2 wt%, Cu 0.05 to 0.4 wt%
At least one selected from the group consisting of Ti and V
The seed contains 0.003-0.05wt% in total, and the balance is A
and aluminum alloy overhead wire compression connecting pipe comprising unavoidable impurities, said connecting pipe being solution-treated at 515-550 ° C., and then at 150-250 ° C. for 4-36 hr.
An aluminum alloy overhead wire compression connection pipe characterized by being aged.