JPH0327620B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides vibration damping that is ideal for preventing pollution caused by vibration and noise from various transportation systems and large machinery, performance deterioration caused by vibration from various precision machines and electronic equipment, and the harmful effects of various vibrations and noises that exist in the living environment. This paper concerns an Al-Ni vibration absorbing alloy with high performance. Attenuation capacity generally used to compare attenuation capacity
Q ^-1 has a relationship with the vibrational energy ΔE lost during the vibration cycle 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
After applying homogeneous solution heat treatment to an alloy containing 20% nickel at a temperature below the melting point of 250°C or higher, cold working is performed at a rate of 5% or higher to increase dislocations, and if necessary, the temperature is reduced to 250°C or lower. The object of the present invention is to provide a vibration-absorbing alloy which is heat-treated at a temperature of 100 to 100 mm and has a large damping capacity due to the hysteresis phenomenon and at the same time has 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 sufficiently stirred to form a uniform molten metal.Then, the alloy is poured into a sand mold or metal mold, and an ingot is poured into an ingot. Build. Next, this ingot is subjected to the following heat treatment. (A) For homogeneous solution treatment, heat at a temperature as high as possible, e.g., below the melting point of the alloy, at a temperature of 250°C or higher, for 5 minutes to 100 hours (preferably 30 minutes or more), and then rapidly cool it or heat it at 1°C per second.
Cool slowly at the following speed. (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 processed with a cold working ratio of 5% or more in (B) at a temperature of 250℃ or less for 1 minute or more (preferably
(30 minutes to 500 hours) and then rapidly cooled, or slowly cooled at a rate of 1°C per second or less. In addition, when dissolving, a flux of 5% or less of the total amount of MgCl ₂ , borax, CaF ₂ , KCl, etc. is added as a blocking agent, and a total amount of Mg, Be, etc. is added as a deoxidizing agent.
0.5% or less may be added. The reason why homogeneous solution treatment is carried out in step (A) is because the inhomogeneity of components may occur in the ingot due to the temperature difference in each part of the ingot during solidification of the molten metal and the comparative difference between the solid and liquid phases. This is to make the ingredients homogeneous. 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,
Although it is necessary to raise the heating temperature and lengthen the heating time, if the weight of the molded product is small, it may be heated at a relatively low temperature for a short time. The reason for this is that unless the solution treatment is sufficiently performed, the performance of the product, such as the damping capacity, cannot be made uniform. The solution treatment process (A) followed by the cold working process (B) is an essential process in order to increase the dislocation density due to processing strain and obtain a large damping capacity due to the hysteresis phenomenon. , is also necessary to increase the tensile strength of the molded article. In order to increase the damping capacity, cold working of 5% or more is enough to achieve the objective, but when the cold working rate is as high as 70 to 95% or when alloys with a large amount of Ni are added. Some materials are difficult to form by bending, deep drawing, punching, etc. For this reason, if the product after cold working in step (B) is heated to a temperature of 250℃ or less in the next step (C), the damping capacity and strength will not deteriorate significantly and it can be bent, deep drawn, punched, etc. at room temperature. Molding becomes easier. In this case, when the heating temperature is set to 250℃ or higher, the elongation increases rapidly to 24% or higher, but the damping capacity
This is not preferable because Q ^-1 decreases to 4×10 ^-3 or less. Next, examples of the present invention will be described. Example A total of 100 g of metal having the composition shown in Table 1 was melted in an alumina crucible in a high-frequency induction electric furnace while passing argon gas to the surface, and cast into an iron mold.
A 10 mm ingot was obtained. Next, this was heated at 500° C. for 5 hours and slowly cooled, then cold swaged and drawn into a 1.1 mm wire, and a 150 mm long wire was cut from this to serve 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 . The damping capacity Q ^-1 and tensile strength of Al-based alloys depend on the cold working rate. As an example, Figures 1 and 2 show the damping capacity Q ^-1 and Tensile strength σ _t
The relationship between and the cold working rate is shown respectively. Both the damping capacity Q ^-1 and the tensile strength σ _t increase with increasing cold working rate, which is a result of the dislocation density increasing with increasing working strain. By this, the attenuation capacity Q ^-1 which is the object of the present invention
= 5% to obtain 6×10 ^-3 or more (γ _n =10×10 ^-6 )
It can be seen that it is necessary to perform the above cold working. Next, Table 1 shows the relationship between cold working rate and damping capacity Q ^-1 for Al-Ni binary alloys.

[Table] As is clear from Table 1, aluminum subjected to 95% cold working has a damping capacity Q ^-1 of 4 x 10 ^-3 , making it unsuitable as a vibration absorbing material for the purpose of the present invention.
It can be seen that when 0.1% or more of nickel is added to aluminum, a large value of Q ⁻¹ =6×10 ⁻³ or more, which is the object of the present invention, 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. 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 and the workability decreases due to brittleness.
It is necessary to anneal at a temperature below ℃. When annealing at a temperature below 250℃, the elongation increases, making it easier to process, and the damping capacity 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. In addition, when the annealing temperature is raised to 250°C, the elongation increases rapidly to 25% or more, but the damping capacity Q ^-1 becomes 4 x 10 ^-3 or less, and the object of the present invention cannot be obtained. Furthermore, the specific gravity ρ of the alloy of the present invention is 7 to 7 of that of general metals.
The tensile strength σ t is considerably smaller than 9 g/cm ³ , and the tensile strength σ _t is considerably higher than 10 Kg/mm ² for cold-worked aluminum. For example, sample No. 1 of the example has σ _t =19
Kg/mm ² , ρ=2.8g/cm ³ . Finally, the reason for limiting the composition of the alloy of the present invention will be described. First, in the Al--Ni vibration absorbing alloy of the present invention, Ni not only contributes to improving the damping capacity Q ^-1 but also strengthens the alloy. The reason for limiting the Ni content to 0.1 to 20% by weight is that if the lower limit of the composition is not met, sufficient damping ability for the purpose of the present invention cannot be obtained, and if the upper limit of the composition is exceeded, the damping ability deteriorates. This is also because cold working becomes impossible. In addition, in order to obtain the required damping ability, strength, and workability, sufficient homogeneous solution treatment is performed by heating at a temperature of 250°C or higher and lower than the melting point for a long time of 100 hours or less for homogeneous solution treatment. Absolutely necessary. Note that performing cold working at a cold working rate of 5% or more is an absolutely necessary condition for increasing 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 homogeneous solid solution treatment is performed by heating at higher temperatures and for a longer period of time, the state of dispersion of Ni particles in the aluminum matrix becomes homogeneous. When this is subjected to cold working at a cold working rate of 5% or more, Ni particles are finely dispersed.
Dislocation density increases. When this dislocation density increases, when vibration is applied from the outside, the applied external force (vibration, impact, torsion, compression, tension, etc.) disappears as thermal energy etc., causing vibration damping. be. Therefore, in order to increase the attenuation capacity, it is necessary to
Long-term heating at higher temperatures and cold working of 5% or more are sufficient to achieve the objective, but when the cold working ratio is increased to 70% to 95%, and when alloys with a large amount of Ni are added. Depending on the composition of the
Some products are difficult to form by deep drawing, punching, etc. For this reason, when reheated for a long time at a low temperature of 250°C or lower, 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, the reheating process is
If the temperature exceeds 250°C, 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 synthesis of the present invention can be applied to various transportation systems, internal combustion engines for automobiles, large machines, moving parts of electronic equipment, 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.

[Brief explanation of drawings]

Figure 1 is a characteristic curve diagram showing the relationship between damping capacity Q ^-1 and cold working rate when an Al-5%Ni alloy is heated at 500℃ for 5 hours, slowly cooled, and then cold worked. 2 is a characteristic curve diagram showing the relationship between the tensile strength σ _t and the cold working rate of the same alloy as in FIG. 1. FIG.

Claims (1)

[Claims] 1. Consists of 0.1 to 20% nickel and the balance aluminum by weight, and has a damping capacity Q ^-1 of 6 with an increased dislocation density due to cold working at a cold working rate of 5% or more.
An Al-Ni vibration-absorbing alloy characterized by having a resistance of ×10 ^-3 or more. 2. An alloy consisting of 0.1 to 20% nickel and the balance aluminum by weight is heated at a temperature of (A) below the melting point of the alloy or above 250°C for 5 minutes to 100 hours and then rapidly cooled or at a rate of 1°C per second or below. (B) A method for producing an Al-Ni vibration absorbing alloy, characterized in that the damping capacity Q ^-1 is made to be 6×10 ^-3 or more by performing slow cooling at a cold working rate of 5% or more. 3 An alloy consisting of 0.1 to 20% nickel and the balance aluminum by weight is heated at a temperature of (A) below the melting point of the alloy or above 250°C for 5 minutes or more and 100 hours or less, and then rapidly cooled or at a rate of 1°C per second or less. After slow cooling, (B) Processing with a cold working rate of 5% or more (C) Processing of (B) with a cold working rate of 5% or more at a temperature of 250°C or less for 1 minute or more 500°C The damping capacity Q ^-1 can be reduced to 6 by applying heat treatment in the order of heating for less than 1 hour and rapid cooling, or slow cooling at a rate of 1°C or less per second.
A method for producing an Al-Ni vibration absorbing alloy, characterized in that it has a vibration absorbing alloy of ×10 ^-3 or more. 4. MgCl ₂ , borax,
A method for producing an Al-Ni vibration absorbing alloy according to any one of claims 2 and 3, in which a total amount of 5% or more of flux selected from CaF ₂ and KCl is added. 5 During dissolution, the total amount selected from Mg and Be is 0.5
% or less of a deoxidizing agent is added.