JPH04347A - Aluminum alloy high damping material and its production - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is an aluminum alloy vibration damping material that has excellent vibration damping properties and is used as a structural member that dislikes vibrations in audio equipment, precision equipment, automobiles, etc. The present invention relates to a manufacturing method thereof.

[Conventional technology]

Generally, when an object is vibrated, the amplitude increases at a certain frequency (fr) (Figure 1). This frequency is called the resonant frequency. If the maximum amplitude at the resonance frequency is Ao, this energy is 172 because the amplitude is AO/12
(-3 dB in dB representation). If this frequency width (half width, 3 dB value width) is Δf, the loss coefficient η is expressed by the following equation.

η-Δf/fr A material with a large value of this loss coefficient η has excellent vibration damping properties, and vibrations are rapidly damped when external force is removed. The loss coefficient η of ordinary metal materials is 0.001 or less.

Conventionally, Fe-
Cr-based, Mn-Cu-based, Zn-Al-based, Ni-
Alloys such as Ti-based alloys are known.

Furthermore, Mg and Mg-Zr based cast materials are also known as vibration damping materials.

[Problem to be solved by the invention] Fe-Cr system, Mn-Cu system, Zn-An system, Ni
Alloys such as -Ti-based alloys have high vibration damping properties, but have a common drawback of high specific gravity, making them unsuitable when attempting to reduce the weight of equipment. On the other hand, Mg and Mg-Zr based cast materials also exhibit great vibration damping properties and have the advantage of having a low specific gravity, but have the disadvantage that they cannot be cold worked at all.

(Means for Solving the Problems) In view of this, and as a result of various studies, the present invention has developed a method for producing an aluminum alloy vibration damping material that has a low specific gravity and is easy to cold work.

That is, the invention according to claim 1 contains 0.1 to 20 wt% of Ni, and further contains a total of 0.05 to 10 wt% of one or more of Cu, Mn, Mg, Cr, and Hf, with the balance remaining. It is an aluminum alloy vibration damping material characterized by consisting of AN and inevitable impurities, and the invention according to claim 2 contains 0.1 to 20 wt% of Si, and further contains Cu,
An aluminum alloy vibration damping material comprising a total of 0.05 to 10 wt% of one or more of Mn, Mg, Cr, and Hf, with the remainder consisting of Al and unavoidable impurities. In the invention described in item 3, Ni0.1 to 2
Contains 0 wt%, and further contains Cu, Mn, Mg, Cr, H
A total of 0.05 to 10 of one or more of f.
Including iit%, remaining AI! A method for producing an aluminum alloy vibration damping material, characterized in that an aluminum alloy ingot consisting of unavoidable impurities is subjected to plastic working with an area reduction rate of 30% or more, so that the loss coefficient η is 0.006 or more, The invention according to claim 4 contains 0.1 to 20 wt% of Si,
Furthermore, it contains one or more of Cu, Mn, Mg, Cr, and Hf in a total of 0.05 to 15 wt%, and the balance is A! A method for producing an aluminum alloy vibration damping material, characterized in that an aluminum base metal ingot consisting of unavoidable impurities is subjected to plastic working with an area reduction rate of 30% or more, so that the loss coefficient η is 0.006 or more. be.

Here, the area reduction rate is a value expressed by the following equation from the cross-sectional area (So) of the material and the cross-sectional area (S) of the product in plastic working such as rolling and extrusion.

S.

[Function] Damping materials are classified into dislocation type, composite phase type, ferromagnetic type, and twin type depending on their vibration damping mechanism, and the vibration damping material according to the present invention falls under the dislocation type.

When Ni or Si is added to aluminum, fine Al-Ni
System or A/! -3i-based compounds are uniformly distributed in the aluminum matrix. When vibration is applied to such a material,
The dislocations introduced by plastic working are An-Ni system or A
/! -3I repeats temporary attachment/detachment to the i-based compound and absorbs vibrational energy. Due to this effect,
It dampens vibrations applied to the material extremely quickly. Addition of Ni or Sl is sufficient to exhibit this effect, but in addition Cu, Mn, Mg,
When one or more of Cr and Hf is added,
These also form respective fine compound phases, and dislocations are repeatedly temporarily attached to and detached from these compounds, and vibration energy is absorbed, so that vibration damping properties can be further improved.

As mentioned above, Ni or Si is added to form a compound that is extremely effective in improving vibration damping properties.
The content was limited to 1 to 20 wt%.
If it is less than ht%, the amount of the compound distributed in the matrix is small and the vibration damping effect is insufficient. If it exceeds 20 wt%, the effect will be saturated, the distribution of the compound will become non-uniform, and cold working will become difficult.

Cu, Mn, Mg,
One or more of Cr and Hf is added,
The reason for limiting the total content to 0.05 to 1Qwt% is that if it is less than 0.05wt%, the amount of the compound distributed in Matri Nox is small and the vibration damping property improvement effect is insufficient, and if it exceeds 10wt%. This is because the effect becomes saturated and the workability decreases.

Note that Ti and B, which are usually added as refiners for the casting structure,
is preferably added in an amount of 0.05 wt% or less. Also, normal AI such as Fe! The impurities contained in the metal are 0.
If it is 5 wt% or less, the effects of the present invention will not be impaired.

The Af gold alloy with the above composition was melted and cast using conventional methods to produce A! It is made into an alloy ingot. This aluminum alloy ingot is subjected to homogenization treatment if necessary. This homogenization treatment is performed to make the distribution state of the added elements more uniform, but the
It may be heated at a temperature of 600°C for several hours. The Al alloy ingot in this state has excellent vibration damping properties compared to normal AN ingot, but the area reduction rate of this Aff alloy ingot is 3.
Vibration damping properties are greatly improved by applying plastic working of 0% or more. That is, by adding plastic working, the dislocation density increases, and as mentioned above, the effect of absorbing vibration energy by repeatedly releasing 7 m of temporary fixation of dislocations from the compound is exhibited, and the vibration damping property is improved.

The plastic working may be performed by hot working, cold working, or cold working after hot working, and may be performed by any means such as rolling, extrusion, drawing, and forging.
The area reduction rate should be 30% or more, and the loss coefficient η should be 0.006 or more. If the loss coefficient η is less than 0.006, the vibration damping property is insufficient, and the necessary characteristics as a vibration damping material cannot be obtained. The loss coefficient improves as the amount of plastic working increases, and a higher loss coefficient can be obtained with cold working than with hot working, but the area reduction rate from the ingot to the final processed product is 30% or more. If so, a loss coefficient η of 0.006 or more can be obtained regardless of hot working or cold working, and sufficient vibration damping properties can be obtained as a vibration damping material.

In addition, annealing is commonly performed to adjust strength and elongation.
Even if it is applied after hot working or during cold working, the effects of the present invention will not be impaired. Similarly, temper annealing, which is applied to the final processed product to adjust strength and elongation, tends to deteriorate vibration damping properties because it reduces dislocations introduced by plastic working, but at 400°C There is no particular problem if it is kept at the following temperature for about 24 hours or less.

〔Example〕

Next, the present invention will be explained in detail with reference to Examples.

Example 1 An Al alloy having the composition shown in Table 1 was melted and cast to a thickness of 50 mm.
The ingot had a width of 120 m and a length of 300 mm.

After drilling, a homogenization treatment was performed at 500°C for 10 hours, and a plate material with a thickness of 5 m was obtained by hot rolling and cold rolling (area reduction rate due to plastic working was 90%). A test piece with a thickness of 2 m, a width of 10Il11, and a length of 250iIL11 was cut out from this, and its vibration damping property (loss coefficient η) was evaluated by the cantilever vibration method.

That is, one end of the test piece is chucked and random vibration is forcibly applied using an oscillator, and the vibration of the test piece is detected. The input/output amplitude ratio in the frequency range of this input vibration and the detected (output) vibration is determined using a two-channel fast Fourier transform (FFT).

The resonance frequency (fr) showing the maximum amplitude ratio and the frequency width (8f) that is 3 dB lower than the maximum amplitude ratio were measured, and the loss coefficient η was determined by the following equation.

η=Δf/fr The value of this loss coefficient η is also listed in Table 1.

As is clear from Table 1, barriers 1 to 6 of the alloy composition of the present invention
has a large loss coefficient η and excellent vibration damping properties. On the other hand, the loss coefficient η
The value of N0. No. 8 to 9 could not be subjected to plastic working.

Example 2 An AI2 alloy having the composition shown in N113 in Table 1 was melted and cast to form an ingot with a diameter of 300 m and a length of 400 mm.
A homogenization process was carried out for 10 hours at °C. This was extruded into a round bar having the diameter shown in Table 2. From this, Example 1
Similarly, a strip-shaped test piece with a thickness of 2 m, a radius of 10 circles, and a length of 250 mm was cut out, and the vibration damping property (loss coefficient η) was evaluated by the cantilever vibration method. The results are also listed in Table 2.

The vibration damping properties (loss coefficient η) were evaluated using the cantilever vibration method in the same manner as in Example 1. The results are also listed in Table 3.

As is clear from Table 2, M11-1 by the method of the present invention
No. 4 has a large loss coefficient η and excellent vibration damping properties.

On the other hand, the comparative method NCL15, which has a low area reduction rate, had a loss coefficient η of 0.006.

Example 3 A2 alloy having the composition shown in Table 3 was melted and cast to a thickness of 50 mm.
The ingot was 120 meters wide and 300 meters long.

This was homogenized before and after the surface at 500°C for 10 hours, and then hot rolled and cold rolled into a plate with a thickness of 5 mm (
The area reduction rate due to plastic working is 90%), and the thickness is 2m +
As is clear from Table 3, a test piece with a width of 10 am and a length of 250 am was cut out.
26) all exhibit a loss coefficient η of 0.006 or more,
Has excellent vibration damping properties. On the other hand, the comparative alloy material (N0.27), which deviates from the alloy composition of the present invention, had a low loss coefficient η, and the comparative alloy material (N0.28.29) could not be subjected to plastic working.

Example 4 An Af alloy ingot with a diameter of 300 m and a length of 400 plates was prepared by melting and casting an Affi alloy having the composition shown in N023 in Table 3, and was extruded under the conditions shown in Table 4 to form a round bar. was created.

From this, as in Example 1, the thickness is 2 (goods), the width is 100w,
A test piece with a length of 250+ma was cut out, and the loss coefficient η was determined in the same manner as in Example 1. The results are also listed in Table 4.

No. table FIG. 1 is a vibration resonance curve diagram.

Claims (4)

[Claims] (1) Contains 0.1 to 20 wt% of Ni, and further contains Cu,
An aluminum alloy vibration damping material comprising a total of 0.05 to 10 wt% of one or more of Mn, Mg, Cr, and Hf, with the remainder being Al and inevitable impurities. (2) Contains 0.1 to 20 wt% of Si, and further contains Cu,
An aluminum alloy vibration damping material comprising a total of 0.05 to 10 wt% of one or more of Mn, Mg, Cr, and Hf, with the remainder being Al and inevitable impurities. (3) Contains 0.1 to 20 wt% of Ni, and further contains Cu,
Plastic working with an area reduction rate of 30% or more on an aluminum alloy ingot containing a total of 0.05 to 10 wt% of one or more of Mn, Mg, Cr, and Hf, and the balance being Al and unavoidable impurities. A method for producing an aluminum alloy vibration damping material, characterized in that the loss coefficient η is set to 0.006 or more. (4) Contains 0.1 to 20 wt% of Si, and further contains Cu,
Plastic working with an area reduction rate of 30% or more on an aluminum alloy ingot containing a total of 0.05 to 15 wt% of one or more of Mn, Mg, Cr, and Hf, and the balance being Al and unavoidable impurities. A method for producing an aluminum alloy vibration damping material, characterized in that the loss coefficient η is set to 0.006 or more.