JPH05271872A - Steel excellent in damping capacity - Google Patents

Abstract

PURPOSE:To provide steel provided with high strength and excellent damping capacity. CONSTITUTION:The objective damping steel has a chemical compsn. contg. 0.1 to 1.5% Mn and 1.2 to 6% V or furthermore contg. one or more kinds among 0.1 to 1.0% Si, 0.01 to 9% sol.Al, <=8.0% Cr, <=1.0% Ni and <=2.0% Mo, and the balance Fe with inevitable impurities, and in which the content of C, P, S, N and 0 in the impurities is respectively regulated to <=0.03%, <=0.2%, <=0.05%, <=0.01% and <=0.005%.

Description

Detailed Description of the Invention [Industrial applications]

In recent years, vibrations generated by industrial machines and machine tools, and noise and vibrations generated by transportation facilities on railway bridges, road bridges for automobiles, etc., have become a frequent social pollution problem. As a general method, a "material that absorbs or shields sound" is used or a "structure that does not easily resonate with vibration" is devised to reduce noise and vibration.

In recent years, the tendency toward comfortable living above the conventional level has become stronger, so that a quieter room is desired, for example, in automobiles, and driving noises are limited to various electric products at home. No reduction is required.

The present invention relates to steel having excellent ability to damp noise and vibration when applied to members such as building structures, automobiles and electric appliances, that is, "vibration damping".

[0004]

2. Description of the Related Art As a steel material having excellent vibration damping property, a "composite vibration damping steel plate in which a polymer viscoelastic substance is sandwiched between two steel plates" has been conventionally known. Since the viscoelastic substance has a low heat resistant temperature, it cannot be used at high temperatures, and welding is also difficult.

On the other hand, it is known that "graphite cast iron" exists as a single iron-based material having vibration damping properties. However, since graphite cast iron has a high carbon content, it has insufficient workability and toughness. It was a material that could not be used as a rolled material.

Separately from this, "steel material containing high Cr or high Al" is known as a single rolled steel material having vibration damping property (Japanese Patent Laid-Open No. 52-73118).
See JP-A-58-2262, etc.). However, the strength of these steel materials is low and the vibration damping characteristics cannot be said to be sufficient.

Therefore, the object of the present invention was to provide a steel having high strength and excellent vibration damping property.

[0008]

Therefore, the present inventors have
The following findings were obtained through intensive research to achieve the above object. That is, "pure iron", which has low strength and poor workability in hot working, is not suitable as a structural material, but it is known that it is a ferromagnetic material and has excellent vibration damping properties. Therefore, the inventors of the present invention seek a way to improve the properties required for structural materials such as strength without deteriorating the good vibration damping property of pure iron, and study from various viewpoints such as devising the component system. By repeating the above, the following items could be confirmed.

A) In order not to impair the good vibration damping property found in pure iron or to further improve it, the content of C, P, S, N and O as impurities should be reduced as much as possible. Is important, b) It is effective to add an appropriate amount of Mn to improve the hot workability without deteriorating the vibration damping property of pure iron, c) Furthermore, an appropriate amount of V is added to the above materials. Then, the ferrite single phase can be maintained even in the high temperature region, and the strength increase and the further vibration damping property improving effect can be achieved.

D) Further, the combined addition of Si and Al is also effective in improving the vibration damping property of the above-mentioned materials, and in order to secure the superior vibration damping property, addition of these appropriate amounts can be a preferable means.

E) On the other hand, Cr, Mo and Ni have the effect of increasing the strength of the above materials without significantly reducing the vibration damping properties thereof, and the addition of appropriate amounts of these is a very effective means for improving the strength of the materials. obtain,

The present invention has been completed based on the above-mentioned findings and the like. "The chemical composition of steel is: Mn: 0.1 to 1.5% (hereinafter,% representing a component ratio shall be% by weight), V : 1.2 to 6% or Si: 0.1 to 1.0%, sol.Al: 0.01 to 9%, Cr:
It also contains one or more of 8.0% or less, Ni: 1.0% or less, Mo: 2.0% or less, and the balance is Fe and unavoidable impurities, and the content of C, P, S, N and O in the impurities is respectively. C: 0.03% or less, P: 0.2% or less, S: 0.
It has a major feature in that it has excellent vibration damping properties and sufficient strength as a structural material by being regulated to 05% or less, N: 0.01% or less, O: 0.005% or less ”. ing.

[0013]

In general, a so-called "magnetostriction phenomenon" is observed in pure iron and steel, which are generally ferromagnetic materials at room temperature, when they are magnetized, they are distorted in the direction of magnetization. On the contrary, in such a material, when a stress is applied from the outside, the spontaneous magnetization rotates so as to relieve the stress, and the domain wall moves. Therefore, when the material as described above is hit or vibrated, the vibration becomes a sound and propagates in the substance, but the vibration causes the direction of the spontaneous magnetization to rotate and induce the movement of the domain wall. Then, elastic energy is consumed at that time, and the vibration is damped at an early stage.

According to the present invention, the energy of vibrational waves or sound waves is easily converted into magnetic energy according to the above mechanism, and by devising the composition system of steel so that high strength can be obtained, high strength and good control can be obtained. Although the steel having the vibrating property has been realized, the reason why the chemical composition of the steel is numerically limited as described above in the present invention will be described in more detail together with its action.

Mn Mn has an effect of improving hot workability and strength without adversely affecting the good vibration damping property of iron, but if the content is less than 0.1%, the desired effect due to the above effect is exerted. The effect is not obtained, while if the content exceeds 1.5%, the adverse effect on the vibration damping property cannot be ignored.
The content was set to 0.1-1.5%. Of course, it is desirable that the Mn content is small from the viewpoint of vibration damping property.
It can be said that it is preferable to limit the Mn content to 0.5% or less.

When V V is added in an appropriate amount, the ferrite single phase is maintained even in a high temperature range, and the vibration damping characteristics are remarkably improved.
However, if the V content is less than 1.2%, its effect is small, while if it exceeds 6%, the toughness deteriorates. Therefore, the V content is set to 1.2 to 6%.

C solid solution C suppresses the movement of the domain wall and significantly reduces the vibration damping property. Therefore, in order to secure the desired characteristics, it is necessary to suppress the carbon content to an extremely low carbon content of 0.03% or less.

Although P P has an action of increasing strength, its content is
If it exceeds 0.2%, the toughness is noticeably reduced. Therefore,
In order to secure the desired characteristics, it is necessary to suppress the P content to 0.2% or less.

S S is an element that reduces hot workability and toughness, and it is necessary to reduce the S content to 0.05% or less in order to secure desired hot workability and toughness.

Like N C, it is an element that suppresses the movement of the domain wall and significantly reduces the vibration damping ability. Therefore, it is necessary to suppress the N content to 0.01% or less in order to obtain a desired good vibration damping property.

O 2 O is also an element that markedly reduces vibration damping and toughness. Therefore, in order to secure the desired good vibration damping and toughness,
It is necessary to reduce the O content to 0.005% or less.

Si and sol.Al The combined addition of Si and Al exerts a more preferable effect for improving the vibration damping property of steel, and therefore it is a preferable means to carry out the addition as necessary. However, if the Si content is less than 0.1%, or the Al content is less than 0.01% in sol.Al amount, the desired effect cannot be obtained, while the Si content exceeds 1.0%, On the contrary, if the Al content exceeds 9% in sol.Al content, vibration damping property and toughness decrease will be caused. Therefore, Si content is 0.1 to 1.0%, Al content is sol.Al content. At 0.01-9%
And decided respectively.

Cr, Ni, and Mo all of these elements have the effect of improving the strength of the steel by solid solution strengthening, so one or more kinds of them are added as necessary. However, if added excessively, the vibration damping property will be deteriorated. Therefore, the upper limit is 8.0% for Cr content, the upper limit is 1.0% for Ni content, and the upper limit is for Mo content.
2.0% each.

Next, the effects of the present invention will be described more specifically by way of examples.

EXAMPLES First, steels having respective chemical compositions shown in Tables 1 and 2 were melted.

[0025]

[Table 1]

[0026]

[Table 2]

Next, each of these steels was finished at a temperature of 110.
Hot rolled to a thickness of 10 mm at 0 ° C, then "1000 ° C x 1"
A round bar tensile test piece having a diameter of 4 mm and a vibration damping test piece having a thickness of 50 mm, a width of 50 mm and a length of 300 mm were cut out from the material subjected to the heat treatment for "time", and the tensile strength and the vibration damping property were investigated.

The vibration-damping property was evaluated by attaching a steel ball having a diameter of 11 mm to the tip of a pendulum having a length of 300 mm and causing the test piece to collide with the test piece from a position of 90 degrees.
“Maximum sound pressure” collected by a measurement microphone installed at a remote location
And "the time from the maximum sound pressure to 20 dB attenuation" were measured. The results are shown in Table 3.

[0029]

[Table 3]

From the results shown in Table 3, the steel of the present invention has higher strength than the conventional steel, and further, the maximum sound pressure of the collision noise is small and the impact sound is attenuated in an extremely short time. Can be confirmed to be good. On the other hand, the comparative steel has a large maximum sound pressure and a long damping time and is inferior in vibration damping property. In addition, the conventional steel has good vibration damping property but low strength. I understand.

[0031]

[Summary of Effects] As described above, according to the present invention, it is possible to provide a steel having high strength and excellent vibration damping property, and to be used as a member for industrial machinery, transportation equipment, household electric appliances and the like. By applying it, it is possible to significantly reduce the generation of noise and vibration and bring about extremely useful effects in industry.

Claims (4)

[Claims] 1. A weight ratio of Mn: 0.1 to 1.5%, V: 1.2 to 6%, the balance being Fe and inevitable impurities, and the content of C, P, S, N and O in the impurities. Are C: 0.03% or less, P: 0.2% or less, S: 0.
Steel with excellent vibration damping characteristics, characterized by having a content of 05% or less, N: 0.01% or less, and O: 0.005% or less. 2. By weight ratio, Mn: 0.1 to 1.5%, V: 1.2 to 6%, Si:
0.1 to 1.0%, sol.Al: 0.01 to 9%, the balance consisting of Fe and unavoidable impurities, and the content of C, P, S, N and O in the impurities is C: 0.03% or less, P : 0.2% or less, S: 0.
Steel with excellent vibration damping characteristics, characterized by having a content of 05% or less, N: 0.01% or less, and O: 0.005% or less. 3. A weight ratio of Mn: 0.1 to 1.5%, V: 1.2 to 6%, Cr: 8.0% or less, Mo: 2.0% or less, Ni:
It also contains one or more of 1.0% or less and the balance is Fe and inevitable impurities, and the content of C, P, S, N and O in the impurities is C: 0.03% or less, P: 0.2% or less, respectively. S: 0.
Steel with excellent vibration damping characteristics, characterized by having a content of 05% or less, N: 0.01% or less, and O: 0.005% or less. 4. The weight ratio of Mn: 0.1 to 1.5%, V: 1.2 to 6%, Si:
0.1 to 1.0%, sol.Al: 0.01 to 9%, Cr: 8.0% or less, Mo: 2.0% or less, Ni:
It also contains one or more of 1.0% or less and the balance is Fe and inevitable impurities, and the content of C, P, S, N and O in the impurities is C: 0.03% or less, P: 0.2% or less, respectively. S: 0.
Steel with excellent vibration damping characteristics, characterized by having a content of 05% or less, N: 0.01% or less, and O: 0.005% or less.