JPH09104950A - High damping alloy and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a high damping alloy having high damping capacity and high toughness by specifying the compsn. composed of C, Si, Mn, P, S, Cr, Al, N and Fe and the (200) diffraction intensity ratio. SOLUTION: A high damping alloy having a compsn. contg., by weight, <=0.02% C, 0.01 to <0.5% Si, <0.2% Mn, <=0.010%P, <=0.005% S, <0.5% Cr, 0.002 to 0.060% Al and <=0.006% N, furthermore contg., at need, one or more kinds among 0.05 to 2.5% Cu, 0.05 to 2.5% Ni, 0.05 to 4.5% Mo, 0.005 to 0.2% Nb, 0.005 to 0.2% V, 0.005 to 0.1% Ti and 0.0003 to 0.005% B, moreover contg. one or two kinds of 0.001 to 0.05% Ca and 0.001 to 0.1% rare earth metals, and the balance Fe with inevitable impurities, in which the (200) diffraction intensity ratio is regulated to >=2.5 and, preferably, having <=100μm grin size is obtd. This high damping alloy can be obtd. by regulating hot rolling and tempering conditions in the alloy having the prescribed compsn.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a damping alloy having a high damping property, a damping alloy having a high toughness as a structural material for ships, bridges, industrial machines and constructions, and a manufacturing method thereof. .

[0002]

2. Description of the Related Art Recently, ships, bridges, industrial machines and buildings tend to be required at the same time to have high damping properties in addition to toughness which is a basic characteristic of structural materials. That is, for example, the problem of suppressing noise and vibration during high-speed railway running on a bridge, large-scale civil engineering, and construction work by the damping effect of the structural material itself, and having sufficient toughness as a structural member is attempted. To do.

Conventional iron-based materials used as members for the purpose of damping property instead of resin sandwich type damping steel plate are high in hysteresis due to irreversible motion of domain wall movement under the action of alternating stress due to vibration. In order to obtain a damping property, a ferrite former is added to make the structure into a ferrite single phase, and it is divided into two types: a material to which Al and Si are added and a material to which Cr is positively added.

As an example of the former, Japanese Patent Laid-Open No. 4-99148
As described in Japanese Patent Publication, the Al content is up to 7.05% and S
There is a ferromagnetic damping alloy with i added up to 4.5%. An example of the latter is a ferromagnetic damping alloy with 8 to 30% of Cr as described in JP-A-52-73118. There are vibration alloys. Further, in JP-A-6-220583 and JP-A-5-302148, Mn is 0.
There is a ferromagnetic damping alloy containing 1 to 0.2% or less and 1 to 5% of Cr. In addition, the inventors of the present invention filed Japanese Patent Application No. 6-2.
No. 58982 has Mn of 0.2 to 2.5% and Cr of 1 to 5
%, A ferromagnetic damping alloy was proposed.

Also, Ryohei Tanaka, damping material (its function and application), published by Kosaido, March 1992, p.192-197, as a ferromagnetic alloy, external stress induces movement of magnetic domain wall and vibration due to hysteresis loss. It is described that energy is absorbed.

[0006]

However, among the above alloys, the alloy described in JP-A-4-99148 is A
Since the upper limit of the amount of l and Si added is not appropriate, it causes the formation of coarse Al-based and Si-based inclusions, and depending on the use conditions, this acts as a point where fracture occurs, so that there is a problem that toughness decreases.

In addition, since the alloy described in JP-A-52-73118 has an excessive Cr content, the toughness of the Cr-based inclusions may be reduced as described above. Furthermore, JP-A-6-2
In 20583 and Japanese Unexamined Patent Publication (Kokai) No. 5-302148, since toughness improvement measures are not taken positively, low toughness may pose a problem. In addition, Japanese Patent Application Hei 6
It can be said that -258982 is still at an insufficient level in terms of vibration damping because it prioritizes securing toughness.

On the other hand, most of the literature on damping materials describes the mechanism of damping alloys, and there are methods for improving them, specific component systems, manufacturing methods, and methods for simultaneously satisfying toughness in addition to damping characteristics. Nothing has been written about. An object of the present invention is to provide a damping alloy having excellent damping properties, damping properties and high toughness, and a method for producing them.

[0009]

Means for Solving the Problems The gist of the present invention achieved to solve the above problems is as follows. (1)% by weight, C: 0.02% or less, Si: 0.01
% Or more, less than 0.5%, Mn: less than 0.2%, P: 0.
010% or less, S: 0.005% or less, Cr: 0.5%
Less than, Al: 0.002% or more, 0.060% or less,
N: 0.006% or less, a balance Fe and unavoidable impurities, and a (200) diffraction intensity ratio of 2.5 or more.

(2) Further, in weight%, Cu: 0.05
~ 2.5%, Ni: 0.05-2.5%, Mo: 0.0
5 to 4.5%, Nb: 0.005 to 0.2%, V: 0.
005-0.2%, Ti: 0.005-0.1%, B:
The vibration damping alloy according to (1), wherein the damping alloy has a (200) diffraction intensity ratio of 2.5 or more, and contains 0.0003 to 0.005%.

(3) Further, in weight%, Ca: 0.00
1 to 0.05%, REM: 0.001 to 0.1%, 1
The damping alloy according to (1) or (2), characterized in that the damping alloy has a (200) diffraction intensity ratio of 2.5 or more.

(4) In the alloy according to any one of (1) to (3), the (200) diffraction intensity ratio is 2.5 or more,
A vibration damping alloy having a crystal grain size of 100 μm or less and high toughness. (5) The alloy according to any one of (1) to (3) is hot-rolled at a heating temperature of 1000 to 1150 ° C., a rolling reduction of 30 to 70% at 900 ° C. or less, and a rolling finishing temperature of 800 ° C. or less. After that, it is cooled to room temperature and tempered or annealed at 650 ° C to 950 ° C, and a heat treatment for annealing is performed.

(6) The alloy according to any one of (1) to (3) has a heating temperature of 1000 to 1150 ° C., a rolling reduction of 900 ° C. or less of 30 to 70%, and a rolling finishing temperature of 650 to 8
After hot rolling at 00 ° C, cooled to room temperature, 650 ° C to 95 ° C.
A method for producing a vibration damping alloy, characterized by having high toughness by tempering or annealing heat treatment at 0 ° C. (7) For the alloy according to any one of (1) to (3), the heating temperature is 1000 to 1150 ° C, the rolling reduction at 900 ° C or lower is 30 to 70%, and the rolling finishing temperature is Ar _{1 to} 20 ° C to Ar.
After hot rolling at ₁ + 50 ° C, cool down to room temperature,
A method for producing a vibration damping alloy, characterized by having high toughness by tempering or annealing heat treatment at 950 ° C.

[0014]

The present invention has been made in view of the above circumstances, and has achieved high vibration damping property due to hysteresis due to irreversible motion of domain wall movement under the action of alternating stress due to vibration. Therefore, it is based on pure iron-based components in which various elements, inclusions, and precipitates that are harmful to the domain wall movement are generated, which hinders the domain wall movement and greatly impairs vibration damping properties.

Further, in the past, since the crystal grain boundary hinders the domain wall movement, the vibration damping property was improved only by coarsening the grain. However, as a result of various studies by the inventors, the vibration damping by the coarsening has been performed. As an alternative to the method for improving the vibration resistance, it has been found that if the (200) diffraction intensity is increased to facilitate the domain wall movement, the vibration damping property is significantly improved. By increasing the (200) diffraction intensity, the <100> orientation that is one of the orientations included in the (200) plane and is parallel to the steel sheet surface can be enhanced. That is, the direction of easy magnetization is strengthened in a direction parallel to the steel sheet surface. It is a new discovery that the damping property is improved by strengthening the easy magnetization direction. This (20
0) It was found that the vibration damping property is improved by setting the diffraction intensity ratio to 2.5 or more. (200) Diffraction intensity ratio is 2.5
With the above, the loss factor, which is an index of damping performance, is 0.0
From the viewpoint of vibration damping performance, the higher the (200) diffraction intensity ratio, the better, but from the viewpoint of other steel properties such as toughness, the (200) diffraction intensity ratio is practically 2. The range of 5 to 12.0 is preferable, and as a result, it is preferable to secure the loss factor of 0.02 to 0.05. Here, the (200) diffraction intensity ratio is obtained by measuring the (200) diffraction intensity at a quarter thickness position in the plate thickness direction by X-ray diffraction, and measuring the (200) diffraction intensity of a random sample material in which a specific orientation is not strengthened or controlled. ) The ratio to the diffraction intensity was obtained. As a result of this study, the maximum value of the (200) diffraction intensity ratio was about 15.

In order to increase the (200) diffraction intensity ratio, it is necessary to carry out low-temperature rolling.
This can be achieved by setting the rolling reduction at 0 ° C. or less to 30% or more. Therefore, the rolling finishing temperature is 800 ° C. or lower. Further, as a result of a detailed study for improving the vibration damping property, it was found that by setting the rolling finishing temperature to Ar ₁ −20 ° C. to Ar ₁ + 50 ° C., the (200) diffraction intensity ratio was further improved and the vibration damping property was further improved. Found out.

Next, in order to improve the toughness, the crystal grain size is set to 10
It is necessary to make it 0 μm or less. When the rolling finishing temperature is lower than 650 ° C. in the manufacturing method for setting the (200) diffraction intensity ratio to 2.5 or higher, the crystal grain size may exceed 100 μ, so the rolling finishing temperature is set to 650 ° C. or higher. After hot rolling, tempering or annealing heat treatment is necessary in order to increase the (200) diffraction intensity ratio and reduce the strain introduced into the steel sheet by rolling. Is lower, the upper limit temperature is 9
50 ° C.

Next, the reasons for limitation of the present invention will be described. Since C acts as an obstacle to the movement of the domain wall even if it is in a solid solution state or is precipitated as a carbide and reduces the vibration damping property, the lower the C is, the more preferable the upper limit is 0.02%. Si is important as a deoxidizer, so 0.01% or more must be added.
If added in excess of 0.5%, it acts as an obstacle to domain wall movement in the solid solution state and reduces the vibration damping property.
0%.

Mn is a solid solution strengthening element and has no effect on improving the vibration damping property and toughness, and the addition thereof increases the cost. Therefore, it is limited to less than 0.2%. P and S form a non-metallic intervening portion in steel and segregate to impede the movement of the magnetic domain wall to lower the vibration damping property. Therefore, P is 0.010% or less, S
Is 0.005% or less.

Al, like Si and Mn, is an important element as a deoxidizing material, and is an important element for improving vibration damping property and strength. It is necessary to secure at least 0.005%, but excessive addition causes inclusions such as Al ₂ O ₃ and compound with N to form precipitates such as AlN, leading to deterioration of vibration damping and toughness. Therefore, the upper limit is limited to 0.060%. Cr is a ferrite former, which is an element that coarsens the crystal grains by adding it, and slightly improves the vibration damping property, but at the same time leads to a decrease in toughness, and since it is an expensive element, the addition amount is reduced as much as possible. Therefore, the upper limit is 0.5.
Limit to less than%.

N, which acts as an obstacle to the movement of the domain wall even if it is in a solid solution state or is precipitated as a nitride, lowers the vibration damping property, so that it is preferably as low as possible, and the upper limit is made 0.006%. Furthermore, Cu, Ni, Mo, Nb, which is added as necessary,
V, Ti, and B are elements effective in increasing strength, and the above amount was set as the lower limit so that the effect is not insufficient, and the above amount was set as the upper limit as the range in which vibration damping and toughness were not reduced.

Further, Ca, R added as necessary
EM is an element effective in improving the toughness, and the above amount was set as the lower limit as a range in which the effect was not insufficient, and the above amount was set as the upper limit as the range in which the toughness was not lowered and the vibration damping property was not lowered. Regarding the manufacturing conditions, the heating temperature is set to 1150 ° C. or lower in order to make the heated austenite grains fine and increase the (200) diffraction intensity ratio, and further set to 1000 ° C. or higher in order to eliminate the temperature deviation in the steel sheet during heating.

Regarding the rolling conditions, in order to raise the (200) diffraction intensity ratio, it is necessary to roll at 30% or more at 900 ° C. or lower, but if the rolling reduction exceeds 70%, the load on the rolling mill becomes large. Also, the rolling time becomes long and this causes a cost increase, so the upper limit is made 70%. The rolling finishing temperature is 800 ° C. or lower because the rolling is performed at 900 ° C. or lower and 30% or higher. However, if the rolling finish temperature is lower than 650 ° C., ferrite rolling occurs and the grain size may exceed 100 μ, resulting in low toughness. The lower limit is 650 ° C.

Further, the rolling finishing temperature is Ar ₁ -20 ° C.
By setting the temperature to Ar ₁ + 50 ° C., the (200) diffraction intensity ratio is further improved and the vibration damping property is further improved. After hot rolling and cooling to room temperature, tempering or annealing heat treatment is required to further improve the (200) diffraction intensity ratio and reduce the strain introduced into the steel sheet by rolling.
Although heat treatment is performed at 0 ° C or higher, the upper limit temperature is 950 ° C because the (200) diffraction intensity ratio becomes weak when heat treatment is performed at high temperature.
And

[0025]

[Examples] First, matchmaking alloys having the ranges of components shown in Tables 1 and 2 were prepared, and a plate-shaped test piece having an original thickness of 40 mm width and 400 mm length was machined from this, and the vibration damping property was measured by the mechanical impedance method. I went.

[0026]

[Table 1]

[0027]

[Table 2]

Among the alloys shown in Tables 1 and 2, Steels A to E are alloys within the composition range of the present invention, and Steels F to L are alloys outside the composition range of the present invention. The various properties of these steels manufactured under the manufacturing conditions shown in Tables 3 and 4 are also shown in the table.

[0029]

[Table 3]

[0030]

[Table 4]

Each steel sheet was hot-rolled, cooled to room temperature, and then heat-treated. No. 1 to 6 are examples of the present invention, and No. 7
-17 are comparative examples. No. 1-3 and 7-13 are plate thickness 2
5mm, No. 4 is 2.5mm thick, No. 5 and 6 is 50m thick
m, Nos. 14 to 17 have a plate thickness of 40 mm. Invention No. 1
Has a (200) diffraction intensity ratio of 2.5 or more and high vibration damping performance (η ≧ 0.02). In the invention Nos. 2 to 6, the rolling finishing temperature is 650 ° C. or higher, the (200) diffraction intensity ratio is 2.5 or higher, the crystal grain size is 100 μm or less, and high vibration damping performance (η ≧ 0.02 ) And high toughness (≧ 100 J). Since the present invention Nos. 3 and 4 contain a selective element effective for increasing the strength, the present invention Nos. 5 and 6 have higher strength.
Has a higher toughness (≧ 120 J) because it contains a selective element effective for increasing the toughness.

Comparative Example No. 7 has a (200) diffraction intensity ratio of 2.5 or more, but has a crystal grain size of more than 100 μ and a high C,
Vibration damping performance and toughness are low. Comparative Example No. 8 has a (200) diffraction intensity ratio of 2.5 or more and a crystal grain size of 100 μ or less, but has high Si and low vibration damping performance. Comparative Example No. 9, 10
Has a (200) diffraction intensity ratio of 2.5 or more and a crystal grain size of 1
Although it is less than 00μ, Comparative Example No. 9 has a high P and No. 1
0 has high S and low vibration damping performance. Comparative example No. 11 is (2
00) The diffraction intensity ratio is 2.5 or more, and the crystal grain size is 100μ.
Although below, Cr is high and toughness is low. Comparative example No. 1
No. 2 has a (200) diffraction intensity ratio of 2.5 or more and a crystal grain size of 100 μ or less, but has a high Al content and low vibration damping and toughness. Comparative Example No. 13 has a (200) diffraction intensity ratio of 2.5 or more and a crystal grain size of 100 μ or less, but has a high N and a low vibration damping performance. Comparative Example No. 14 has a high heating temperature, Comparative Example No. 15 has a low rolling reduction of 900 ° C. or less, (200)
Diffraction intensity ratio is low, crystal grain size is over 100μ, and vibration damping performance and toughness are low. Comparative example No. 16 has a low heat treatment temperature,
The (200) diffraction intensity ratio is low and the crystal grain size is 100 μ or less, but the vibration damping performance is low. Comparative Example No. 17 has a high heat treatment temperature, a low (200) diffraction intensity ratio, and a grain size of 1
Although it is less than 00μ, the vibration damping performance is low.

Next, various characteristics of the steels P, Q, and R of the alloys in the composition range of the present invention shown in Table 5 are shown together with those produced under the production conditions of the present invention shown in Table 6.

[0034]

[Table 5]

[0035]

[Table 6]

The invention Nos. 18, 19 and 20 are examples in which the rolling finishing temperature is in a more desirable range. All plate thickness is 2
It is 0 mm. Ar ₁ of steels P, Q and R is 675 respectively
C, 680 C and 670 C. Invention No. 18, 1
In 9 and 20, the rolling finishing temperature is Ar ₁ + 50 ° C. to Ar ₁ -2.
Within the range of 0 ° C., the (200) diffraction intensity ratio is 4 or more, the vibration damping performance is good (η ≧ 0.03), and the rolling finishing temperature is Ar ₁ + 50 ° C. to Ar ₁ −20 ° C. It has better vibration damping performance than those of the present invention Nos. 21 to 23, which are not within the range.

[0037]

EFFECTS OF THE INVENTION According to the present invention, a ship, a bridge, an industrial machine, which is required to have damping performance and high toughness and damping performance at the same time,
Supply of structural materials for construction becomes possible, and the effect on the industrial world is extremely large.

Claims (7)

[Claims] 1. By weight%, C: 0.02% or less, Si: 0.01% or more and less than 0.5%, Mn: less than 0.2%, P: 0.010% or less, S: 0. 0.005% or less, Cr: less than 0.5%, Al: 0.002% or more, 0.060% or less, N: 0.006% or less, and the balance Fe and inevitable impurities, (2
00) A damping alloy having a diffraction intensity ratio of 2.5 or more. 2. Further, in weight%, Cu: 0.05 to 2.5%, Ni: 0.05 to 2.5%, Mo: 0.05 to 4.5%, Nb: 0.005. 0.2%, V: 0.005 to 0.2%, Ti: 0.005 to 0.1%, B: 0.0003 to 0.005%, and one or more kinds are contained, (200) The damping alloy according to claim 1, wherein the diffraction intensity ratio is 2.5 or more. 3. Further, by weight, Ca: 0.001 to 0.05% and REM: 0.001 to 0.1% are contained in one or two kinds, and a (200) diffraction intensity ratio is 2. 5
It is above, The damping alloy of Claim 1 or 2 characterized by the above-mentioned. 4. An alloy according to claim 1, which has a (200) diffraction intensity ratio of 2.5 or more, a crystal grain size of 100 μ or less, and high toughness. alloy. 5. The alloy according to claim 1 is hot-rolled at a heating temperature of 1000 to 1150 ° C., a rolling reduction of 30 to 70% at 900 ° C. or less, and a rolling finishing temperature of 800 ° C. or less. After that, it is cooled to room temperature and tempered or annealed at 650 ° C to 950 ° C, and a heat treatment for annealing is performed. 6. The alloy according to claim 1, wherein the heating temperature is 1000 to 1150 ° C., the rolling reduction at 900 ° C. or less is 30 to 70%, and the rolling finishing temperature is 650 to 800.
After hot rolling at ℃, cool to room temperature, 650 ℃ ~ 950 ℃
A method for producing a vibration-damping alloy, characterized by having high toughness after being subjected to tempering or annealing heat treatment in. 7. The alloy according to any one of claims 1 to 3.
At a heating temperature of 1000 to 1150 ° C. and 900 ° C. or less
The rolling reduction is 30 to 70%, and the rolling finishing temperature is Ar. ₁-20 ° C
~ Ar₁After hot rolling at + 50 ° C, cool to room temperature,
High temperature after tempering or annealing heat treatment at 0 ℃ -950 ℃
A method for producing a vibration damping alloy having toughness.