JPS6242984B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is designed to reduce vibrations that are most suitable for preventing pollution caused by the vibrations and noise of various transportation systems and large machines, performance deterioration caused by vibrations of various precision machines and electronic equipment, and the harmful effects of various vibrations and noises that exist in the living environment. This invention relates to an Al-Co-based vibration absorbing alloy with high damping ability and a method for manufacturing the same. Attenuation capacity generally used to compare attenuation capacity
Q ^-1 has a relationship with the vibrational energy ΔE lost during one cycle of vibration and the total vibrational energy E as shown in the following equation. Q ^-1 = 1/2π·ΔE/E In other words, the larger the value of Q ^-1 , the smaller the amplitude becomes in a shorter time and the greater the damping effect. Conventionally known vibration absorbing alloys include Fe-based alloys such as dientalloy, Mn-Cu alloys, and Al-Cu alloys.
-Ni-based alloys and Ni-Ti-based alloys. Fe-based vibration-absorbing alloys such as dientalloy and Mn-Cu-based alloys have a large damping capacity, but their specific gravity is around 8 g/ ^cm3 , making them unsuitable when reducing the weight of equipment. Ni-based alloys and Ni-Ti-based alloys have a drawback in that they have poor cold workability and are completely impossible to cold work. In order to obtain a vibration-absorbing alloy that is lighter than conventional vibration-absorbing alloys, the present invention is based on aluminum, which has a very small specific gravity of 2.7 g/ ^cm3 , and has a weight ratio of 0.1 to
20% cobalt and less than 50% lead, antimony, 40
% or less of cerium, 20% or less of tantalum, 15% or less of iron, niobium, zirconium, 10% or less of titanium, calcium, and 3% or less of boron in a total amount of 0.1 to 50%. The object of the present invention is to provide a vibration-absorbing alloy which has a large damping ability and strong strength by subjecting a multi-component alloy to cold working at a cold working rate of 5% or more to increase dislocations and, through the hysteresis phenomenon, to have a large damping ability and high strength. Next, a method for manufacturing the alloy of the present invention will be explained. First, an alloy with the above composition range is melted in an ordinary melting furnace in air, an inert gas, or a vacuum, and then thoroughly stirred to make a uniform molten metal, which is then cast into a sand mold or metal mold. Make ingots. Next, this ingot is subjected to the following heat treatment. (A) After heating for solution treatment at a temperature as high as possible, for example, at a temperature of 250°C or higher below the melting point of the alloy for 5 minutes or more (preferably 30 minutes or more and 100 hours or less), rapidly cool it or at a rate of 1°C per second or less. Cool slowly. (B) Subsequently, cold working is performed at room temperature by forging, rolling, extrusion, swaging, or drawing at a cold working rate of 5% or more in order to obtain the large damping capacity that is the objective of the present invention. (C) A product that has been cold worked with a cold working rate of 5% or more in (B) is heated at a temperature of 250°C or less for 1 minute or more (preferably 30 minutes or more and 500 hours or less) and then rapidly cooled or cooled every second. Cool slowly at a rate of 1°C or less. When melting, add flux such as MgCl ₂ , borax, CaF ₂ , KCl, etc. in a total amount of 5% or less as a blocking agent, and add metals such as Mg, Be, etc. in a total amount of 0.5% or less as a deoxidizing agent. Good too. The reason why the homogenization treatment is carried out in step (A) is to make the components homogeneous since non-uniformity of components may occur in the ingot. If the heating temperature is high, the heating time can be shortened, and if the heating temperature is low, the heating time must be lengthened. On the other hand, if the weight of the molded object is large, it is necessary to raise the heating temperature and increase the heating time, but if the weight of the molded object is small, it may be heated at a relatively low temperature for a short time. The reason for this is that if homogeneous solution treatment is not performed sufficiently,
This is because product performance such as damping capacity cannot be made uniform. The cold working in step (B) after the homogenization treatment in step (A) is an essential step in order to increase the dislocation density due to processing strain and to obtain a large damping capacity due to the dislocation hysteresis phenomenon. It is also necessary to increase the tensile strength of the molded article. In addition, in order to increase the damping capacity, cold working of 5% or more is enough to achieve the purpose, but if the cold working rate is large or depending on the composition of the alloy, bending,
Some products are difficult to form by deep drawing, punching, etc. Therefore, the cold processed material in step (B)
Heating to a temperature of 250°C or lower makes it easier to form such things as bending, deep drawing, and punching at room temperature. Here, the annealing temperature was set to 250℃ or less because 250
This is because heating to a temperature higher than 0.degree. C. causes a rapid increase in elongation, but a decrease in damping ability. Example 1 Total amount of metal with the composition shown in Tables 1 and 2: 100g
was melted in an alumina crucible using a high-frequency induction electric furnace while passing Ar gas through the surface, and poured into a mold to obtain an ingot with a diameter of 10 mm. Next, this was heated at 500℃ for 5 hours and slowly cooled, and then cold swaged and drawn into a 1.1mm wire.
A mm line was cut and used as a sample. The damping capacity Q ^-1 was measured by the inverted torsion pendulum method at a frequency of about 1 Hz and a maximum strain amplitude γ _n =10×10 ^-6 . Tables 1 and 2 show the values of Q ^-1 when a 95% cold working rate is applied to a multi-component alloy in which one or more of various other elements are added to an Al-Co alloy. be.

【table】

[Table] As is clear from these tables, the cold working rate is 95%.
Aluminum treated with aluminum has a damping capacity Q ^-1 of 4 × 10 ^-3 and is unsuitable as a vibration absorbing material for the purpose of the present invention. When 0.1% or more ^of the total amount ^of
It can be seen that larger values can be obtained. In short, the value of the damping capacity Q ^-1 of the alloy of the present invention is several tens of times larger than the value of the damping capacity Q ^-1 =1×10 ^-3 of general metals. Example 2 A total of 100g of Al-1.0%Co-0.5%Fe alloy was melted in an alumina crucible using a high-frequency induction electric furnace while passing Ar gas to the surface, and cast into an iron mold to form a diameter of 10.
An ingot of mm was obtained. Next, this was heated at 500° C. for 5 hours, slowly cooled, and then cold swaged and drawn into a 1.1 mm wire at a cold working rate of 71%.
This cold processed material was heated to 150℃ for 60 minutes each.
After annealing for 180 minutes, it is slowly cooled and then the length
A 150 mm wire was cut and used as a sample. Attenuation capacity Q ^-1
The measurement was performed using an inverted torsional pendulum method at a frequency of approximately 1 Hz.
The experiment was carried out at a maximum strain amplitude γ _n =10×10 ^-6 . The results are shown in Table 3.

[Table] As described above, in the present invention, as the cold working rate increases from 5% to 95%, the damping capacity increases, but the elongation decreases, the brittleness decreases, and the workability decreases.
It is necessary to anneal at a temperature below 250℃. When annealing at a temperature of 250°C or lower, the elongation increases by at least three times, making it easier to process, and the damping ability decreases slightly, but this is not a problem. This is because the number of dislocations increased by processing is annealed by annealing, resulting in fewer dislocations. Note that when the annealing temperature is raised to 250° C. or higher, the elongation increases rapidly to 25% or higher, but the damping capacity Q ⁻¹ becomes 4×10 ⁻³ or lower, and the object of the present invention cannot be obtained. From the results of the above tests, the ingot of the alloy of the present invention (A)
After cold working with a cold working ratio of 5% or more, heating at a temperature of 250°C or less for 1 minute or more and 500 hours or less increases the elongation El, making it difficult to form by bending, deep drawing, punching, etc. becomes easier. The relationship between cold working, heating temperature, heating time, elongation El, and damping capacity Q ^-1 for the Al-1.0%Co-0.5%Fe alloy in Example 2 is as shown in Table 3. The lower the temperature, the longer the heating time needs to be.
Furthermore, the upper limit of the heating temperature was set at 250°C because if the heating temperature is higher than 250°C, the elongation El becomes very large by 25% or more, but the damping capacity Q ^-1 suddenly decreases to 4 × 10 ^-3 or less, so this invention This is because it is insufficient for the purpose of Furthermore, the specific gravity ρ of the alloy of the present invention is considerably smaller than that of ordinary metals, and the tensile strength σ _t is considerably larger than that of cold-worked aluminum, which is 10 Kg/mm ² .
For example, sample No. 6 in the example has σ _t = 18Kg/mm ² and ρ = 2.8
g/cm ³ , sample No. 9 has σ _t = 25Kg/mm ² , ρ = 2.8g/
cm ³ , sample No. 16 has σ _t = 20Kg/mm ² , ρ = 3.0g/cm ³
It shows. Finally, the reason for limiting the composition of the alloy of the present invention will be described. First, in multi-component alloys, Co and other additive elements Pb, Sb, Ce, Ta, Fe, Nb, Zr, Ti,
Both Ca and B not only contribute to improving the damping capacity Q ^-1 but also strengthen the alloy except for Pb. Co 0.1 to 20% by weight, Pb and Sb 50% or less,
Ce: 40% or less, Ta: 20% or less, Fe, Nb, Zr: 15%
% or less, Ti, Ca 10% or less, and B 3% or less. This is because sufficient strength cannot be obtained with Pb when the above upper limit of the composition is exceeded, and cold working is impossible with other elements. Table 4 shows the general tendency that the component range of each component element in the vibration absorbing alloy of the present invention has on damping ability, mechanical strength, workability, etc.

【table】

[Table] For homogeneous solution treatment, heating at a temperature of 250℃ or higher and lower than the melting point for a long time (100 hours or less) and sufficient solution treatment will reduce the required attenuation capacity.
It is absolutely necessary to obtain strength and workability. Note that performing cold working at a cold working rate of 5% or more is an absolutely necessary condition because it increases the damping capacity by increasing the working strain and dislocation density. The alloy molded body is heated to 250℃ below the melting point of aluminum.
When the homogeneous solid solution treatment is performed by heating at the above high temperature for a long time, the state of dispersion of Co and subcomponent element particles in the aluminum matrix becomes homogeneous. When cold working is performed at a cold working rate of 5% or more, Co and subcomponent element particles are finely dispersed, and the dislocation density becomes large. When this dislocation density increases, the external force (vibration, shock, torsion, compression, tension, etc.) that is applied when vibration is applied from the outside
is annihilated as thermal energy and other energy, resulting in vibration damping. Therefore, in order to increase the attenuation capacity, it is necessary to
Long-term heating at higher temperatures and cold working of 5% or higher are enough to achieve the purpose; however, if the cold working rate is large or depending on the composition of the alloy, bending, deep drawing, punching, etc. Some products are difficult to mold. For this reason, when annealing is performed by reheating at a low temperature of 250°C or lower for a long period of time, the damping capacity and strength do not deteriorate significantly, and forming processes such as bending, deep drawing, and punching become extremely easy. In this case, if the reheating treatment is carried out at a temperature of 250° C. or higher, the attenuation ability will decrease, which is not preferable. As mentioned above, the alloy of the present invention is characterized by having a large damping capacity, being lightweight, having good cold workability, high strength, and being non-ferromagnetic. Therefore, the alloy of the present invention can be applied to various transportation systems, internal combustion engines for automobiles, large machinery, moving parts of electronic devices, parts operated by magnetic fields, various household goods, and structural materials for buildings, etc., and can be used to prevent vibration and noise, Very suitable for weight reduction.

Claims (1)

[Scope of Claims] 1. Cobalt 0.1 to 20%, one or both of lead and antimony 50% or less, cerium 40% or less, tantalum 20% or less, iron, niobium, and zirconium in terms of weight ratio. Any one or more than 15%,
Damping capacity Q ^-1 with increased dislocation density, consisting of 10% or less of one or both of titanium and calcium, 3% or less of boron, a total amount of 0.1 to 50% of one or more of these, and the balance aluminum. An Al-Co-based vibration-absorbing alloy characterized in that the is 6×10 ^-3 or more. 2 By weight, 0.1 to 20% cobalt, 50% or less of one or two of lead and antimony, 40% or less of cerium, 20% or less of tantalum, and one or two of iron, niobium, and zirconium. More than species and less than 15%,
An alloy consisting of 10% or less of one or both of titanium and calcium, 3% or less of boron, a total amount of 0.1 to 50% of one or more of them, and the balance aluminum, (A) 250% below the melting point of the alloy. After heating at a temperature of 5 minutes or more and 100 hours or less at a temperature of 100°C or higher and cooling rapidly or gradually cooling at a rate of 1°C or less per second, (B) Attenuation ability Q ^- A method for producing an Al-Co-based vibration absorbing alloy, characterized in that ¹ is 6×10 ^-3 or more. 3 In terms of weight ratio, an alloy consisting of 0.1 to 20% cobalt and the balance aluminum, with lead as a subcomponent,
50% or less of any one or both of antimony, 40% or less of cerium, 20% or less of tantalum, iron, niobium,
15% or less of any one or more of zirconium, one or more of titanium and calcium10
(A) At a temperature of 250°C or higher below the melting point of the alloy for 5 minutes or more.
After heating for 100 hours or less and rapidly cooling or slowly cooling at a rate of 1°C per second or less, (B) cold working with a cold working rate of 5% or more (C) (B) with a cold working rate of 5% or more Damping capacity Q ^-1 can be achieved by heating the processed material at a temperature of 250°C or less for 1 minute or more and 500 hours or less, and then rapidly cooling it, or slowly cooling it at a rate of 1°C or less per second. 6×
A method for producing an Al-Co-based vibration-absorbing alloy, characterized in that it has a vibration absorbing alloy of 10 ^-3 or more.