JPH09157792A - High damping alloy and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structural material requiring damping property and high toughness by constituting a high damping alloy so that it has a composition containing specific percentages of C, Si, Mn, P, S, Cr, Al, and N and having the balance Fe. SOLUTION: The high damping alloy has a composition consisting of, by weight, <=0.02% C, 0.5-3.5% Si, <0.2% Mn, <=0.01% P, <=0.005% S, 0.5-3.5% Cr, 0.002-0.06% Al, <=0.006% N, and the balance Fe with inevitable impurities. Further, one or more elements among Cu, Ni, Mo, Nb, V, Ti, B, Ca, and REM can be incorporated. The alloy is heated at 1000-1200 deg.C, and draft at <=960 deg.C and rolling finishing temp. are regulated to >=70% and <=860 deg.C, respectively, and tempering is done at 660-960 deg.C. By the procedure, (200) diffraction intensity ratio is regulated to >=3.2. By this method, the high damping alloy having excellent damping property and high toughness can be provided.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a damping alloy having a high damping property and a damping alloy having a high toughness as a structural material for ships, bridges, industrial machines and constructions.

[0002]

2. Description of the Related Art Recently, materials for ships, bridges, industrial machines and buildings tend to be required at the same time to have high vibration damping properties in addition to the basic characteristics of structural materials such as strength and toughness. 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.

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 damping characteristics, it is divided into two types: a material to which Al and Si are added and a material to which Cr is positively added, with the aim of adding a ferrite former to make the structure into a ferrite single phase.

As an example of the former, Japanese Patent Laid-Open No. 4-99148
There is a ferromagnetic alloy containing Al up to 7.05% and Si up to 4.5% as described in JP-A No. 52-73118. 8 to 30% of ferromagnetic damping alloys.

Further, in JP-A-6-220583 and JP-A-5-302148, there is a ferromagnetic damping alloy in which Mn is 0.1 or 0.2% or less and 1 to 5% of Cr is added. . In addition, the present inventors have filed Japanese Patent Application No. 6-258982.
Proposed a ferromagnetic damping alloy containing 0.2 to 2.5% of Mn and 1 to 5% of Cr. In addition, Ryohei Tanaka, Vibration damping material "its function and application", Kosaido, March 1992, P. 1
It is described in 92 to 197 that, as a ferromagnetic alloy, external stress causes the domain wall to move, and the resulting hysteresis loss absorbs vibration energy.

[0006]

However, among these alloys, the alloy described in Japanese Patent Application Laid-Open No. 4-99148 has an inappropriate upper limit regulation of Al and Si addition amounts. This leads to the formation of a substance, which acts as a point of fracture occurrence, resulting in a decrease in toughness. Further, since the alloy described in JP-A-52-73118 is excessively Cr-added, the toughness is lowered by the Cr-based inclusions similarly to the above.

Further, in JP-A-6-220583 and JP-A-5-302148, the toughness is low because there is no positive measure for improving the toughness. In addition, Japanese Patent Application No. 6-
No. 258982 is insufficient in terms of vibration damping because it prioritizes securing toughness. Further, in the literature of damping materials, the mechanism of damping alloy is written, and there is no description about the improvement measures, specific component systems / manufacturing methods, or methods for simultaneously satisfying toughness in addition to damping properties. An object of the present invention is to provide a damping alloy having excellent damping properties and damping properties and high toughness.

[0008]

The gist of the present invention is as follows. (1) C: 0.02% or less by weight%, Si: 0.5
% Or more and 3.5% or less, Mn: less than 0.2%, P: 0.
010% or less, S: 0.005% or less, Cr: 0.5%
Or more, 3.5% or less, Al: 0.002% or more, 0.0
60% or less, N: 0.006% or less, balance Fe
And a (200) diffraction intensity ratio of 3.2 or more, and a damping alloy.

(2) C: 0.02% or less by weight%,
Si: 0.5% or more, 3.5% or less, Mn: 0.2% or more, 2.5% or less, P: 0.010% or less, S: 0.0
05% or less, Cr: 0.5% or more, 3.5% or less, A
1: 0.002% or more, 0.060% or less, N: 0.0
A vibration-damping alloy, which contains not more than 06%, consists of the balance Fe and unavoidable impurities, and has a (200) diffraction intensity ratio of 3.2 or more.

(3) Cu: 0.05-2.
5%, Ni: 0.05 to 2.5%, Mo: 0.05 to
4.5%, Nb: 0.005-0.2%, V: 0.00
5 to 0.2%, Ti: 0.005 to 0.1%, B: 0.
The vibration damping alloy according to (1) or (2), characterized in that it contains 0003 to 0.005% by one kind or two or more kinds.

(4) Ca: 0.001% by weight
0.05% and REM: 0.001-0.1% are contained 1 type or 2 types, The damping alloy in any one of (1)-(3) characterized by the above-mentioned. (5) The damping alloy according to any one of (1) to (4), characterized in that high toughness is ensured by setting the crystal grain size to 120 μm or less.

(6) The heating temperature is 1000 to 1200
℃, 960 ℃ or less rolling reduction of 70% or more, rolling finishing temperature is 860 ℃ or less after hot rolling, cooled to room temperature, 660
The method for producing a vibration-damping alloy according to any one of (1) to (5), which comprises performing a tempering or an annealing heat treatment at ˜960 ° C. (7) The method for producing a vibration-damping alloy according to (6), characterized in that hot rolling is performed at a rolling finishing temperature in the range of 710 to 860 ° C. (8) Rolling finishing temperature range is Ar ₁ + 50 ° C. to Ar ₁
The method for producing a vibration damping alloy according to (6) or (7), characterized in that hot rolling at + 100 ° C. is performed.

[0013]

The present invention has been made in view of the above circumstances, and in order to obtain high damping characteristics due to hysteresis due to irreversible motion of domain wall movement under the action of alternating stress due to vibration, the It is based on pure iron-based components in which the elements that cause harmful harmful elements, inclusions, and precipitates, interfere with domain wall movement, and greatly impair vibration damping are minimized.

Further, in the past, since the crystal grain boundaries hinder 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 achieved. As an alternative to the method for improving the vibration resistance, it has been found that the vibration damping property is significantly improved by increasing the (200) diffraction intensity. By increasing the (200) diffraction intensity, the <100> orientation parallel to the steel sheet surface is strengthened.

That is, the easy magnetization direction is strengthened in the direction parallel to the steel plate surface. It is a new discovery that the damping property is improved by strengthening the easy magnetization direction. This (200)
It was found that the damping property is improved by setting the diffraction intensity ratio to 3.2 or more.

When the (200) diffraction intensity ratio is set to 3.2 or more, the loss coefficient, which is an index of vibration damping property, can be secured to be 0.03 or more, and from the viewpoint of vibration damping performance only (200).
The higher the diffraction intensity ratio, the better, but in consideration of other steel material properties such as toughness, the practical (200) diffraction intensity ratio is 3.2.
A range of 1 to 12.5 is preferred, resulting in 0.0
It is preferable to ensure a loss factor of 3 to 0.06.

Here, the (200) diffraction intensity ratio is (200) at a quarter thickness position in the plate thickness direction by X-ray diffraction.
The diffraction intensity was measured and the ratio to the (200) diffraction intensity of the random sample material in which the specific orientation was not strengthened or controlled was determined. 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, and as a result of examination, 960
It can be achieved by setting the rolling reduction at 70 ° C or lower to 70% or higher.
Therefore, the rolling finishing temperature is 860 ° C. or lower. Furthermore,
As a result of a detailed study for improving the vibration damping property, by setting the rolling finishing temperature to Ar ₁ + 50 ° C. to Ar ₁ + 100 ° C., (2
It has been found that the 00) diffraction intensity ratio is further improved and the vibration damping property is further improved.

Further, when a high strength of 400 MPa or more is required, Mn was found as an element capable of significantly increasing the strength without impairing the vibration damping property and the toughness. By adding 0.2% or more of Mn, both the vibration damping property of loss factor (= η) of 0.03 or more and the strength of 400 MPa or more, or the vibration damping property of η of 0.03 or more and 4
It is possible to satisfy all of the strength of 00 MPa or more and the high toughness of the absorbed energy at 0 ° C. in the V notch Charpy impact test of 80 J or more.

Next, in order to improve the toughness, the crystal grain size is set to 12
It is necessary to make it 0 μm or less. In the manufacturing method for setting the (200) diffraction intensity ratio to 3.2 or more, if the rolling finishing temperature is less than 710 ° C., the crystal grain size may exceed 120 μ, so the rolling finishing temperature is set to 710 ° C. or more. 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
60 ° C.

As described above, the damping property is improved by introducing the texture even in the fine grain structure, and further improvement of the damping property was examined. As a result, it was found that by adding the ferrite formers Si and Cr, some coarse grains were achieved in the process of strain relief heat treatment after hot rolling, and the vibration damping property was further improved. The strength is also increased by adding Si and Cr.

Next, the reasons for limitation of the present invention will be described. C
Is not preferable because it acts as an obstacle to domain wall movement even if it is in a solid solution state or is precipitated as a carbide, and reduces the vibration damping property. Therefore, the upper limit is 0.02%. In addition to being important as a deoxidizing material, Si is an important ferrite former and solid solution strengthening element, so Si is indispensable for improving vibration damping properties.
Addition of 5% or more is required. On the other hand, if added in excess of 3.5%, inclusions such as SiO ₂ are generated, which acts as a point of occurrence of fracture, resulting in a significant decrease in toughness. Therefore, the range of addition of Si is 0.5% or more and 3.5% or less.

Mn is a solid solution strengthening element, has no effect on improving vibration damping property and toughness, and if added, the cost increases. Therefore, Mn is less than 0.2% unless high strength of 400 MPa or more is required. It is good to limit to However,
Especially when high strength of 400 MPa or more is required, Mn is an essential element for securing the strength, and for this purpose, it is necessary to add 0.2% or more, but more than 2.5%. Since the vibration damping property will be deteriorated when added as Mn, the upper limit of the amount of Mn is 2.5%.

P and S form non-metallic inclusions in the steel and segregate to exert a detrimental effect on the movement of the magnetic domain wall, and reduce the vibration damping property. Therefore, P is set to 0.010% or less and S is set to 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. Although it is necessary to secure at least 0.002%, excessive addition causes inclusions such as Al ₂ O ₃ and compounding with N to form precipitates such as AlN, resulting in deterioration of vibration damping and toughness. Therefore, the upper limit is limited to 0.060%.

Cr is a ferrite former, and is an element that causes the crystal grains to become slightly coarse when added.
0.50% or more is added to improve the vibration damping property.
At the same time, the toughness is lowered, and since it is an expensive element, it is preferable to reduce the added amount as much as possible. Therefore, the upper limit is 3.5.
% Or less. N 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, and lowers the vibration damping property, so that it is preferably as low as possible, and the upper limit is made 0.006%.

Further, Cu, N added as necessary
i, Mo, Nb, V, Ti, and B are elements effective for increasing strength, and the above amount is set as the lower limit as a range in which the effect is not insufficient, and as a range in which vibration damping and toughness are not deteriorated. The upper limit was the amount. Further, Ca and REM added as necessary are elements effective for improving the toughness, and the above amount is set as the lower limit as a range in which the effect is not insufficient, and a range in which the toughness rather decreases and the vibration damping property does not decrease. As
The above amount was made the upper limit.

Regarding the manufacturing conditions, the heating temperature is 1200 ° C. or lower in order to make the heated austenite grains fine and the (200) diffraction intensity ratio high, and further 1000 ° C. or higher in order to eliminate the temperature deviation in the steel sheet during heating. And Regarding the rolling conditions, in order to increase the (200) diffraction intensity ratio,
70% or more rolling is required at 960 ° C or less.

The rolling finishing temperature is 860 ° C. or lower because the rolling finish temperature is 960 ° C. or lower and 70% or more is rolled, but 710 ° C.
If the temperature is less than the lower limit, the ferrite region may be rolled, and the crystal grain size may exceed 120 μ, which may lower the toughness. Therefore, the lower limit is 710 ° C.
And Furthermore, the rolling finishing temperature is Ar ₁ + 50 ° C. to Ar ₁
By setting the temperature to + 100 ° C., the (200) diffraction intensity ratio is further improved and the vibration damping characteristics are further improved.

After hot rolling and cooling to room temperature, (20
0) In order to further improve the diffraction intensity ratio and reduce the strain introduced into the steel sheet by rolling, tempering or annealing heat treatment is required, and heat treatment at 660 ° C. or higher is performed, but the (200) diffraction intensity ratio is The upper limit temperature is set to 960 ° C., because heat treatment weakens it at high temperature.

[0031]

Example First, a matchmaking alloy having the composition range shown in Table 1 was prepared, and a plate-like test piece having an original thickness of 40 mm width and a length of 400 mm was processed from this, and the vibration damping property was measured by the mechanical impedance method. Among the alloys shown in Table 1, steel Nos. A to F are alloys within the composition range of the present invention, and steels No. G to O are alloys outside the composition range of the present invention. Table 2 also shows various characteristics of these steels manufactured under the manufacturing conditions shown in Table 2. Each steel sheet having a thickness of 6 mm or more was heat-rolled, then cooled to room temperature and then heat-treated. A sheet having a thickness less than that was hot-rolled, wound, and then heat-treated.

[0032]

[Table 1]

[0033]

[Table 2]

Examples 1 to 7 are examples of the present invention, and Examples 8 to 20 are comparative examples. Examples 1-4 and 8-14 have a plate thickness of 23 mm, Example 5
Is 1.7 mm in thickness, Examples 6 to 7 are 45 mm in thickness, Examples 15 to 20
Has a plate thickness of 22 mm. The inventive example of Example 1 has a (200) diffraction intensity ratio of 3.2 or more and high vibration damping performance (η ≧ 0.03).
0), but the strength is 3 because Mn is less than 0.2%.
It remains at 54 MPa. In Examples 2 to 7, the rolling finishing temperature is 710 ° C. or higher, the (200) diffraction intensity ratio is 3.2 or higher, the crystal grain size is 120 μm or lower, and Mn is added at 0.2% or higher. With strength (≧ 400 MPa),
High damping performance (η ≧ 0.030) and high toughness (≧ 80J)
Having.

Since Examples 4 and 5 contain the selective element effective for increasing the strength, the strength is higher (≧ 430 MPa), and Examples 6 and 7 contain the selective element effective for increasing the toughness.
Further, it has high toughness (≧ 100 J).

Comparative Example 8 has a (200) diffraction intensity ratio of 3.2.
However, the crystal grain size exceeds 120 μm, the C content is high, and the vibration damping performance and toughness are low. Example 9 has a (200) diffraction intensity ratio of 3.2.
As described above, although the crystal grain size is 120 μ or less, Si is low and strength and vibration damping performance are low. In Example 10, the (200) diffraction intensity ratio is 3.2 or more and the crystal grain size is 120 μ or less, but Si is high and the vibration damping performance is low. Examples 11 and 12 are (2
00) The diffraction intensity ratio is 3.2 or more, and the crystal grain size is 120μ.
As follows, Example 11 has a high P, Example 12 has a high S,
Vibration control performance is low. Example 13 has a (200) diffraction intensity ratio of 3.
If it is 2 or more, the crystal grain size is 120 μ or less, but Cr is low, and the strength and vibration damping performance are low.

In Example 14, the (200) diffraction intensity ratio is 3.2 or more and the crystal grain size is 120 μ or less, but Cr is high,
Low toughness. In Example 15, the (200) diffraction intensity ratio is 3.2 or more and the crystal grain size is 120 μ or less, but Al is high,
Low toughness. In Example 16, the (200) diffraction intensity ratio is 3.2 or more and the crystal grain size is 120 μ or less, but N is high and the vibration damping performance is low.

The heating temperature is high in Example 17, and 960 in Example 18.
Low rolling reduction below ℃, low (200) diffraction intensity ratio,
If the crystal grain size exceeds 120μ, vibration damping performance and toughness are low. Example 1
No. 9 has a low heat treatment temperature and a low (200) diffraction intensity ratio,
The crystal grain size is 120 μ or less, but the vibration damping performance is low. In Example 20, the heat treatment temperature is high, the (200) diffraction intensity ratio is low, and the crystal grain size is 120 μm or less, but 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 3 are shown together with those produced under the production conditions of the present invention shown in Table 4. Examples 1, 2,
No. 3 is an example in which the rolling finishing temperature is in a more desirable range.
The plate thickness is all 25 mm. Ar ₁ of the steels P, Q and R are 725 ° C., 730 ° C. and 720 ° C., respectively.

[0040]

[Table 3]

[0041]

[Table 4]

In Examples 1, 2, and 3, the rolling finishing temperature was Ar ₁ +5.
Within the range of 0 ° C. to Ar ₁ + 100 ° C., the (200) diffraction intensity ratio is 4.5 or more, and further excellent vibration damping performance (η ≧
0.040) and the rolling finishing temperature is Ar ₁ + 50 ° C.
It has better vibration damping performance as compared with Examples 4 to 7 which are not within the range of Ar ₁ + 100 ° C.

[0043]

Industrial Applicability According to the present invention, it becomes possible to supply a ship, a bridge, an industrial machine, a structural material for construction, etc., which are required to have vibration damping performance and high toughness and vibration damping performance at the same time. large.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication C22C 38/54 C22C 38/54 38/58 38/58

Claims (8)

[Claims] 1. By weight%, C: 0.02% or less, Si: 0.5% or more, 3.5% or less, Mn: less than 0.2%, P: 0.010% or less, S: 0 0.005% or less, Cr: 0.5% or more, 3.5% or less, Al: 0.002% or more, 0.060% or less, N: 0.006% or less, balance Fe and unavoidable impurities Consists of (2
00) A damping alloy having a diffraction intensity ratio of 3.2 or more. 2. By weight%, C: 0.02% or less, Si: 0.5% or more, 3.5% or less, Mn: 0.2% or more, 2.5% or less, P: 0.010. % Or less, S: 0.005% or less, Cr: 0.5% or more, 3.5% or less, Al: 0.002% or more, 0.060% or less, N: 0.006% or less, The balance consists of Fe and unavoidable impurities.
00) A damping alloy having a diffraction intensity ratio of 3.2 or more. 3. By weight%, Cu: 0.05 to 2.5%, Ni: 0.05 to 2.5%, Mo: 0.05 to 4.5%, Nb: 0.005 to 0. 2%, V: 0.005-0.2%, Ti: 0.005-0.1%, B: 0.0003-0.005%, 1 type (s) or 2 or more types are contained, It is characterized by the above-mentioned. The vibration damping alloy according to item 1 or 2. 4. A weight percentage of Ca: 0.001 to 0.05% and REM: 0.001 to 0.1% are contained in one or two kinds.
The damping alloy according to any one of 3 above. 5. The vibration damping alloy according to claim 1, wherein a high toughness is ensured by setting the crystal grain size to 120 μm or less. 6. A heating temperature of 1000 to 1200 ° C., 96
Rolling rate of 0% or less is 70% or more, rolling finishing temperature is 860
After hot rolling at ℃ or less, cool to room temperature, 660-960
The method for producing a vibration damping alloy according to any one of claims 1 to 5, characterized by performing a tempering or an annealing heat treatment at a temperature of ° C. 7. A rolling finishing temperature range of 710 to 860 ° C.
The method for producing a vibration-damping alloy according to claim 6, wherein hot rolling is performed. 8. The rolling finishing temperature range is Ar ₁ + 50 ° C.
The method for producing a vibration damping alloy according to claim 6, wherein hot rolling at Ar ₁ + 100 ° C. is performed.