JPS595653B2 - Manufacturing method of vibration damping steel plate for processing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a distributed steel sheet that has a significantly high vibration damping ability after cold working (and has a characteristic that the vibration damping ability does not deteriorate over time) and has excellent workability.

In recent years, vibration and noise have come to be seen as problems from various quarters, and various countermeasures are being considered accordingly.

One of the effective countermeasures is to use materials with high vibration damping ability in the vibration-generating parts, and this is also why so-called vibration damping steel plates with high vibration damping ability are needed.

Generally, the vibration damping ability of an alloy is expressed by the magnitude of internal friction Q-1.

Here, Q-1 is the following formula % formula % by.

This Q-1 represents the amount of energy lost per one cycle of strain amplitude, and means that the larger Q-1 is, the greater the rate at which vibrational energy is converted into heat inside the material.

Mn-Cu alloy is a well-known vibration damping material, but it has a low Young's modulus.
It also has the disadvantage of high manufacturing costs.

In addition, there are two types of vibration damping steels that have different vibration damping methods: (1) ferromagnetic type and (2) inclusion type.

The ferromagnetic type (ii) is a type in which the amount of solute C and N in the steel is reduced to facilitate domain wall movement, and vibration is damped by magnetic-mechanical static hysteresis loss. Examples include ferritic stainless steel containing a large amount of Cr, decarburized steel, and Ti-added steel.

What this format has in common is (1) the Q-
(2) In the low strain range (maximum strain amplitude: 1X10-5 or less), strain relief annealing is required at 700℃ or higher after forming. This means that it has drawbacks such as a small Q-1.

On the other hand, the inclusion type (■) contains a large amount of inclusions, and the pores created by processing absorb vibrations.
One example is cast iron.

Compared to the previous ■, this type has a Q -1 in the low distortion range.
However, due to the presence of inclusions, the workability is extremely poor, making cold working almost impossible, and the strength remains unreliable, so it lacks practically essential requirements.

Method of rapidly heating and short-time annealing of highly clean steel
-142421) also belong to the category of inclusion type, so they are inevitably subject to deterioration of workability due to inclusions, and as time passes after processing, they will eventually become Q-1. It has the property of so-called aging deterioration, and its vibration damping effect in actual use is questionable.

In view of the above circumstances, the present invention has been developed to provide a system which has extremely good vibration damping ability after cold working, which does not deteriorate over time, and which also meets practically essential requirements such as workability and strength. The present invention aims to provide a method for manufacturing a shaken steel plate.

That is, the present invention includes: (1) C: 0.004 to 0.80%, Si: 4% or less, M
n: 0.15-3.0%, S2 0.042-0.
25%, and satisfies Mn (%)/S (%) ≧ 4, and further Sol, Al: 0.015 to 0.20%
steel, with the remainder consisting of Fe and unavoidable impurities.

■ C: 0.004-0.80%, Si: 4% or less, M
n: 0.05-3.0%, Pb: 0.03-0
．． 30%, and further contains Sol, A1: 0.015 to 0.
20%, with the remainder consisting of Fe and unavoidable impurities.

■ C: 0.004-0.80%, Si: 4% or less, M
n: 0.05-3.0%, Pb: 0.03-0
．． 30%, S: 0.042-0.25%, and further S
Steel containing 0.015 to 0.20% of Al, and the remainder consisting of Fe and inevitable impurities.

Using any of the above steels ■, ■, ■, hot rolling,
Alternatively, after further cold rolling, decarburization annealing is performed at a temperature of 650 to 750°C to adjust the C content to 0.003% or less, and if necessary, temper rolling is performed to a C content of 0.3% or more. The gist is the manufacturing method of damping steel plates.

The skin pass rolling in the method of the present invention is required only when cold working is not performed in actual use, in which case the skin pass rolling significantly improves Q-1.

When used after being cold worked by the user, the cold working can be expected to have the same effect as the above-mentioned skin pass rolling, so pressure adjustment at the manufacturing stage is not necessary.

According to the method of the present invention, Q-1 after the above-mentioned pressure adjustment or cold working and aging at room temperature for one month is the maximum strain amplitude of the plate surface of about 0.
It is possible to produce vibration-damping steel plates with excellent properties such as 5X10-5 and 2X10-3 or more, and the elongation (G, L = 50 mm) of 40% or more (in the case of cold-rolled steel sheets).

The root cause of the drawbacks of the conventional ferromagnetic type and inclusion type described above can be said to lie in the vibration damping method itself of each type.

Therefore, the inventors of the present invention have conducted various experimental studies with the intention of developing a new vibration damping steel plate with a vibration damping method different from those of the conventional ferromagnetic type and inclusion type.

As a result, the MnS phase, Pb
If a phase such as PbS phase exists and solid solution C1 and solid solution N are removed as much as possible, only in that case can a significantly high Q-1 be secured by cold working, and this Q-1 is We discovered a new fact that it does not deteriorate over time, that is, due to aging.

The details of the vibration damping mechanism in this case have not yet been fully elucidated, but it is likely that <MnS phase, Pb phase, PbS phase
It is considered that the vibration of dislocations introduced into the interface between the phase and the Fe phase by cold working exhibits an excellent vibration damping function.

It is understood that such a vibration damping function does not deteriorate over time if there is no solid solution C or solid solution N that tends to collect on dislocation lines.

According to detailed experiments by the present inventors, in order not to reduce the vibration damping function, the solid solution C1 and the solid solution N should each be reduced to 0.
It was confirmed that the ratio should be adjusted to 0.003% or less.

By the way, it is actually not easy to stably keep the C and N amounts themselves within the extremely low range as mentioned above in the melting stage, and a significant cost increase is unavoidable.

However, as in the present invention, the amount of C is normally set at the melting stage,
According to a method in which a steel plate is decarburized and annealed in a wet hydrogen atmosphere, a solid solution C content of 0.003% can be easily achieved at low cost.

In this case, there is no problem as long as the thickness of the steel plate is 3.0 mm or less.

On the other hand, N can be removed by long-term annealing in dead hydrogen, but this method requires a long time and is not a good idea.

If the N in the steel is fixed as AIN by adding 0.015% or more of AI as in the present invention, there will be no solid solution N even if the amount of N in the steel is high, and this method is the most advantageous in terms of cost. ,
Moreover, it can be said to be an effective method for removing solid solution N.

The reasons for limiting each requirement in the present invention will be explained below.

C: The amount of C in molten steel does not affect the vibration damping ability.

However, if it is less than 0.004%, the melting cost increases.

On the other hand, if it exceeds 0.8%, a large amount of cold rolling power is required, making production difficult in practice.

Si: Although it is not necessarily necessary to add Si, the higher the content, the easier decarburization becomes, and it is also preferable in terms of strength.

However, if it exceeds 4%, hardening will be significant and cracks will easily occur during manufacturing.

When attempting to secure a high Q-1 using the Mn:MnS phase, a high Q-1 cannot be obtained unless the content is 0.15% or more.

This is because if it is less than 0.15%, MnS is easily dissolved.

When using a Pb phase or a PbS phase with the expectation of the same effect as the MnS phase, the content must be 0.05% or more to prevent hot embrittlement.

However, if the content exceeds 3.0%, melting becomes difficult.

S: has the effect of improving vibration damping ability through the formation of a MnS phase or a PbS phase, but the effect is insufficient if it is less than 0.042%.

However, if it exceeds 0.25%, workability will deteriorate.

Pb: Effective in improving vibration damping ability, but if it is less than 0.03%, the effect is insufficient.

However, if it exceeds 0.3%, workability deteriorates, which is not preferable.

The above s and pb may be added alone or in combination.

Mn/S: If Pb is not added, the ratio must be 4 or more to prevent hot embrittlement.

Sol, Al: has the effect of fixing N as AIN, but if it is less than 0.015%, this effect cannot be expected sufficiently.

On the other hand, if the content exceeds 0.2%, it will only increase the cost.

Decarburization annealing Generally, if the plate thickness is 3.0 mm or less, decarburization to C≦0.003% in wet hydrogen is sufficiently possible5.

A suitable temperature is 650 to 750°C.

That is, below 650°C, the diffusion rate of C is slow, resulting in low decarburization efficiency (and above 750°C, an austenite phase is generated, so decarburization slows down).

If the temper rolling after decarburization annealing does not exceed 0.3%, Q
1 cannot be expected to improve sufficiently.

As mentioned earlier, when cold working is performed by the user, skin pass rolling is not required.

The higher the rolling reduction ratio in skin-pass rolling, the better the Q-1 will be, but the upper limit value will change depending on the capacity of the rolling mill and the degree of change in mechanical properties due to skin-pass rolling, so the upper limit value should be particularly limited. isn't it.

Hereinafter, the present invention will be explained in detail based on Examples.

Example 1 Steel having the components shown in Table 1 was melted in a converter, made into a 210 mm thick slab by continuous casting, and then made into a 210 mm thick slab in a heating furnace.
It was heated to 0°C and hot rolled at a final finishing temperature of 860°C.

After pickling, it was cold rolled to a thickness of 1.0 mm and heated at 700°C.
Normal annealing or decarburization annealing was performed.

The annealing atmosphere is normally 10% H2 + 90% N2, with a dew point of about -10°C, and in the case of decarburization annealing, it is 15% H2 +
The atmosphere was 85% N2 and the dew point was about +20°C.

Note that a loose coil was used in decarburization annealing.

The soaking time was 10 hours in all cases.

Annealed product, pressure adjusted to 1.0%, left at room temperature for 1 month,
A tensile test according to JI85 was conducted in a direction perpendicular to the rolling direction: T direction, and at the same time, Q-1 was measured.

The measurement of Q-1 was performed at a frequency of about 280 Hz using a capacitive transverse vibration method.

The maximum strain amplitude on the plate surface at this time is 0.2 to 1.0X10
-5.

The Q-1 measurement specimen size is 1.0mm thick x 10mm wide x 1207117M long, and measurements were taken as-is, immediately after 2% tensile processing, and after aging at 50°C for 3 days.
This was done in the seed state.

This assumes press molding during experimental use and subsequent changes over time.

These results are summarized in Table 2.

In addition, when we analyzed the C content of each test steel sheet, the normally annealed sheet remained the same as the molten steel shown in Table 1, but the decarburized annealed material decreased to 0.001 to 0.002%. Was.

In Table 2, the decarburized steel sheets A1 and B1, in which S or pb is within the range of the present invention, have a satisfactory value of Q-1 in any state.

On the other hand, although S or PB is within the range of the present invention, the steel plates A2 and B2 which have been subjected to normal annealing have particularly significant aging deterioration in Q-1.

Furthermore, if both s and pb are out of the range of the present invention, Q-1 will not be high as shown by C2 even if it is a decarburized steel sheet.

The results of the tensile test showed that there was no significant difference between the two, and it was revealed that there was no concern about workability and strength even with the present invention.

Example 2 Regarding steels A and B in Table 1, hot-rolled plates with a thickness of 1.8 mm manufactured in the same manner as in Example 1 were heated to 15% H2 + 85% N2.
, dew point +20℃, soaking time at 700℃ for 30 minutes ~
Decarburization annealing was performed for 10 hours.

From this hot rolled steel plate, 1.0mm thickness x 10mm width x 12O
A test piece of length ii was taken and Q-1 was measured after aging at 2% tension + 50°C for 3 days.

Figure 1 shows the C analysis value of the annealed plate and the Q-
1 is shown.

From the same figure, it can be seen that a significantly high Q' can be obtained when C≦0.003% or less.

Example 3 Steel having the composition shown in Table 3 was melted into a 20mm thick steel billet, heated to 1150°C, hot rolled to 3.2mm at a finishing temperature of 830°C or higher, and immediately cooled in air. did.

After pickling, it was cold rolled to 1.0 mm, and then decarburized annealed at 700° C. for 10 hours.

The atmosphere was 15% H285% N, and the dew point was about 30°C.

After pressure adjustment, aging treatment was performed at 50° C. for 3 days, and Q-1 was measured. The final C amount varied from 0.001 to 0.002%.

The results are shown in Table 4.

The following is clear from Table 4:

That is, /161 has too low S, so Q-1 is small, and /I63 and /I6.7 have low Sol and AI, so they also do not have sufficient Ql.

Further, /16.6 has Mn/S<4 and has cracks due to hot rolling.

On the other hand, Steels No. 2, /I64, No. 5, and No. 8 to No. 10 have the steel composition of the present invention, and all exhibit high Ql.

Among them, in /i6.5, in which Pb and S are added in combination, there is no cracking even when Mn / S < 4, and Q -
1 is the highest.

In addition, B, Cr, Cu, etc. are added to /I68-10, but this is aimed at improving strength and corrosion resistance, and such additions do not interfere with securing Q-1. .

As is clear from the above explanation, according to the present invention, the vibration damping ability after cold working (temper rolling) is extremely high, and furthermore, this does not deteriorate due to aging, and there are no problems in terms of workability and strength. It is possible to manufacture damping steel plates, and these damping steel plates can be used in vibration-generating parts of machinery and building structures to reduce vibrations and
It is extremely effective for noise prevention.

[Brief explanation of drawings]

FIG. 1 is a chart showing an example of the relationship between the amount of C and Q −1 after annealing a hot rolled sheet.

Claims (1)

[Claims] IC: 0.004 to 0.80%, Si: 4% or less,
Mn: 0.15-3.0%, S: 0.042
~0.25%, and Mn (%)/S (%) ≧4
and further Sol, Al: 0.015~0
．． After hot rolling or further cold rolling, a steel containing 20% Fe and the remainder consisting of Fe and unavoidable impurities is heated to
A method for producing a damping steel plate for processing, which comprises decarburizing and annealing at a temperature of ~750°C to adjust C to 0.003% or less. 2 C: 0.004 to 0.80%, Si: 4% or less,
Mn: 0.15-3.0%, S: 0.042
Contains ~0.25%, and Mn (%)/S (%)〉4
and further Sol, At: 0.015~0
．． After hot rolling or further cold rolling, the steel contains 20% and the balance is Fe and unavoidable impurities.
A method for producing a vibration damping steel plate for processing, which comprises decarburizing and annealing at a temperature of 50° C. to adjust the C content to 0.003% or less, and then temper rolling to a C content of 0.3% or more. 3 C: 0.004 to 0.80%, Si: 4% or less,
Mn: 0.05-3.0%, Pb: 0.03
~0.30%, further Sol, Al: 0.0
C: 0.00 by hot rolling or further cold rolling and decarburizing and annealing the steel at a temperature of 650 to 750°C to obtain a C: 0.00.
A method for manufacturing a vibration damping steel plate for processing, characterized by adjusting the vibration damping steel plate to 3% or less. 4 C: 0.004 to 0.80%, Si: 4% or less,
Mn: 0.05~3.0%, Pb: 0.03~
Included in 0.30% and further Sol, AI: 0.0
C: 0.00 by hot rolling or further cold rolling and decarburizing annealing at a temperature of 650 to 750°C.
A method for manufacturing a damping steel plate for processing, characterized by adjusting the vibration damping steel plate to 3% or less, and further performing temper rolling to 0.3% or more. 5 C: 0.004 to 0.80%, Si: 4% or less,
Mn: 0.05~3.0%, Pb: 0.03~
0.30%, S: 0.042-0.25%,
Further, the steel containing 0.015 to 0.20% of Sol and Al, with the remainder consisting of Fe and unavoidable impurities, is hot rolled or further cold rolled and then decarburized and annealed at a temperature of 650 to 750°C. A method for manufacturing a damping steel plate for processing, characterized in that C: is adjusted to 0.003% or less. 6 C: 0.004 to 0.80%, Si: 4% or less,
Mn: 0.05~3.0%, Pb: 0.03~
0.30%, S: 0.042-0.25%,
Furthermore, it contains Sol, Al: 0.015 to 0.20%,
The remainder consists of Fe and unavoidable impurities. After hot rolling or further cold rolling, the steel is decarburized and annealed at a temperature of 650 to 750°C to adjust the C content to 0.003% or less, and further to 0.003% or less of C.
A method for manufacturing a damping steel plate for processing, characterized by performing temper rolling of 3% or more.