JP2005298952A - Damping material and its production method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an easily workable high damping material having damping properties more excellent than that of the conventional one and having high strength. <P>SOLUTION: The high damping material is composed of a Cu-Al-Mn-Ni alloy comprising, by mass 3 to 10% Al, 5 to 20% Mn and 0.2 to 10% Ni, and at least one kind of element selected from the group consisting of Co, Fe, Ti, V, Cr, Si, Nb, Mo, W, Sn, Sb, Mg, P, Be, Zr, Zn, B, C, Ag and misch metal by 0.001 to 10% in total provided that the total of the alloy is defined as 100%, and the balance Cu with inevitable impurities. In particular, the Cu-Al-Mn-Ni alloy has a recrystallized structure composed of an austenite(β) single phase in which crystal orientation is uniformized by thermomechanical treatment, or a (β+α) two phases in which the α phase is precipitated into the austenite (β) phase. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vibration damping material and a manufacturing method thereof.

  It is known that shape memory alloys composed of TiNi alloys and copper-based alloys such as Cu-Sn and Cu-Zn exhibit vibration damping as well as remarkable shape memory effect and superelasticity accompanying the reverse transformation of martensite transformation. It has been. TiNi alloy exhibits excellent shape memory and superelasticity near the living environment temperature, so microwave damper, air conditioner wind direction control member, rice cooker steam pressure regulating valve, architectural vent, mobile phone antenna, glasses It has been put to practical use in a wide range of fields such as frames and brassiere frames. TiNi is superior in many respects, such as repeatability and corrosion resistance, compared to copper-based alloys, but has the disadvantage that the cost is 10 times or more that of copper-based alloys. Accordingly, a lower cost shape memory / superelastic alloy has been desired.

  Under such circumstances, many practical researches have been made on cost-effective copper-based shape memory alloys. However, many existing copper alloys such as Cu—Sn and Cu—Zn have poor cold workability, and cold work of 30% or more is impossible, which has been an obstacle to practical use. . For this reason, the refinement of crystal grains has been actively performed in order to improve the cold working rate and mechanical properties.

  In view of the above circumstances, the present inventors have proposed a Cu—Al—Mn type shape memory alloy having a β single phase structure excellent in cold workability. (See Patent Document 1).

  We also propose Cu-Al-Mn alloys with high shape memory characteristics and superelasticity while maintaining excellent workability, members such as wires, plates and pipes made of this alloy, and methods for producing them. (See Patent Document 2).

Furthermore, the present inventors also proposed a vibration damping material made of a Cu—Al—Mn alloy and a manufacturing method thereof (see Patent Document 3). That is, it is a vibration damping material characterized by having a twin structure and a two-phase structure of an austenite (β) phase and a martensite (M) phase. Although the vibration damping material according to this conventional technique has excellent vibration damping characteristics, a high-strength material cannot be obtained because the crystal cannot be made fine. Further, even if high strength is obtained, there is a problem that the processing rate cannot be increased because of high strength.
Japanese Patent Laid-Open No. 7-62472 Japanese Patent Laid-Open No. 2001-20026 JP 2004-10997 A

  The present invention has been made in order to solve the above-described problems of the prior art, and is an improved invention related to a vibration damping material and a method for manufacturing the same. That is, an object of the present invention is to provide a vibration damping material that is superior in vibration damping properties than conventional ones and that is easy to process with high strength.

  The inventors have discovered that by adding Ni to a conventional Cu—Al—Mn alloy, a damping material having excellent damping properties can be obtained even if the crystal is refined.

  Further, the present inventors greatly improve the strength and vibration damping properties by aligning the crystal orientation of the austenite (β) phase in the crystal structure of the copper-based alloy containing Ni, It has been found that even in the martensite (M) phase state, it has high vibration damping characteristics.

  Furthermore, the present inventors have found that the Ni-containing copper-based alloy exhibits a superplastic phenomenon in a certain temperature range by performing an appropriate heat treatment on the Ni-containing copper-based alloy. The present invention has been completed based on such findings.

  That is, the damping material of the present invention is a total of 3 to 10% Al, 5 to 20% Mn, 0.2 to 10% Ni, and the whole alloy as 100% in terms of mass percentage. 0.001 to 10% of Co, Fe, Ti, V, Cr, Si, Nb, Mo, W, Sn, Sb, Mg, P, Be, Zr, Zn, B, C, Ag, and misch metal It is characterized by comprising a Cu—Al—Mn—Ni alloy composed of at least one element selected from the group and the balance of Cu and inevitable impurities.

  In particular, the Cu—Al—Mn—Ni alloy preferably has a recrystallized structure composed of an austenite (β) single phase whose crystal orientation is aligned by a thermomechanical treatment. Moreover, it is preferable that the existence frequency in the said process direction of the crystal orientation of the said austenite ((beta)) single phase measured by the electronic backscattering pattern method is 2.0 or more.

  In the vibration damping material of the present invention, it is desirable that 50% or more of the volume fraction of the austenite (β) phase is transformed into a martensite (M) phase. Furthermore, a two-phase structure in which an α phase is precipitated in the recrystallized structure is preferable.

  In the vibration damping material made of such a Cu—Al—Mn—Ni alloy, the crystal grain size d of the austenite (β) phase is 0.001 <d / w <5 or 0.005 <d / D <10. The tensile strength at room temperature is preferably 300 to 1200 MPa. Note that w is the plate width and D is the wire diameter of the wire (hereinafter, d / w or d / D is referred to as the relative crystal grain size).

  The vibration damping material of the present invention can exhibit a superplastic phenomenon at 350 to 600 ° C. In order to develop the superplastic phenomenon, it is desirable that the crystal grain size of the damping material is 10 μm or less.

  The manufacturing method of the vibration damping material of the present invention as described above includes an ingot forming step in which a raw material containing Cu, Al, Mn and Ni as main components is prepared and melted to form an ingot, and this ingot is hot worked Then, a rough material forming step of obtaining a rough material of a predetermined size by a heat treatment that repeatedly repeats cold working and annealing, and this rough material is subjected to solution treatment (β single phase treatment), quenching treatment and aging treatment. A heat treatment step for obtaining a heat treatment material in which the austenite (β) phase is fixed, or (β + α) biphasic treatment, quenching treatment and aging treatment are performed on the rough material, so that the α phase is 0.1 in the austenite (β) phase. And a heat treatment step of obtaining a heat treatment material deposited by 50% by volume. Here, it is preferable that the total heat treatment after the final annealing is 30% or more in the heat treatment in the coarse material forming step.

  Moreover, it is desirable to further have a strain imparting step for imparting permanent strain to the obtained heat treated material, and the strain imparting step is preferably any one of wire drawing, rolling, and shot peening.

(Cu-Al-Mn-Ni alloy)
The damping material of the present invention has a mass percentage of 3 to 10% Al, 5 to 20% Mn, 0.2 to 10% Ni, and 100% of the whole alloy in total. .001 to 10% Co, Fe, Ti, V, Cr, Si, Nb, Mo, W, Sn, Sb, Mg, P, Be, Zr, Zn, B, C, Ag, and Misch metal It is characterized by comprising a Cu-Al-Mn-Ni alloy having at least one selected element and the balance of Cu and inevitable impurities.

  Here, the reason why the content of Al is 3 to 10% by mass is that if it is less than 3% by mass, an austenite (β) single phase cannot be formed, and if it exceeds 10% by mass, it becomes extremely brittle. . Although more preferable content of Al changes with content of Mn and Ni, it is 6-9 mass%.

  By containing Mn, the composition range in which the austenite (β) phase can exist is expanded to the low Al side, and the cold workability can be remarkably improved. If the Mn content is less than 5% by mass, satisfactory workability cannot be obtained, and an austenite (β) single-phase region cannot be formed. If the Mn content exceeds 20% by mass, dislocation occurs inside the structure. This is because it becomes easy to be introduced, so that the elongation at break is remarkably lowered and the martensitic transformation temperature is lowered at the same time. A preferable Mn content is 7 to 15% by mass.

  Ni is an element that is particularly effective for sufficiently aligning the crystal orientation. If the Ni content is less than 0.2% by mass, the crystal orientation is insufficient, and if it exceeds 10% by mass, the martensitic transformation temperature is remarkably lowered, which is not preferable. A more preferable Ni content is 0.2 to 3.5% by mass.

Furthermore, at least selected from the group consisting of Co, Fe, Ti, V, Cr, Si, Nb, Mo, W, Sn, Sb, Mg, P, Be, Zr, Zn, B, C, Ag, and Misch metal A total of 0.001 to 10% by mass of one kind of element, based on 100% by mass of the entire alloy, has no effect of grain refinement when the content is less than 0.001% by mass, and 10% by mass. This is because if the content exceeds 50%, the martensitic transformation temperature is lowered.
(Damping characteristics)
The structure of the Cu—Al—Mn—Ni alloy is preferably a recrystallized structure composed of an austenite (β) single phase whose crystal orientation is aligned by thermomechanical treatment.

  Since the vibration damping material of the present invention has a recrystallized structure composed of a single phase of austenite (β) with a uniform crystal orientation, the crystal grains can be refined and have high strength and excellent vibration damping properties. Can do.

  The vibration damping material comprising the Cu—Al—Mn—Ni alloy of the present invention is a twin-type vibration damping material, and an interface between the thermoelastic martensite (M) contributing to the shape memory effect and the parent phase. , Or the internal twin boundaries generated in the martensite (M) phase, or the internal friction associated with the movement of the martensite variant (brother phase) phase, etc. Material.

  FIG. 10 shows the relationship between the tensile strength and logarithmic decay rate δ of various materials. In FIG. 10, the horizontal axis is a logarithmic value of tensile strength (MPa), and the vertical axis is a logarithmic decay rate δ.

As can be seen from FIG. 10, the Cu—Al—Mn—Ni alloy of the present invention has a tensile strength in the range of 100 to 1000 MPa as compared with other vibration damping alloys, for example, conventional Cu—Al—Mn alloys. It can be seen that it has an excellent logarithmic decay rate δ (damping ability).
(Production method)
The method for manufacturing a vibration damping material of the present invention includes a step of preparing a raw material containing Cu, Al, Mn, and Ni as main components and melting to form an ingot, followed by hot working the ingot, A rough material forming step for obtaining a rough material of a predetermined size by a heat treatment that repeats cold working and annealing, and the rough material is subjected to β single phase treatment, quenching treatment and aging treatment to fix the austenite (β) phase. Heat treatment step for obtaining a heat treatment material, or heat treatment material obtained by subjecting a coarse material to (β + α) biphasic treatment, quenching treatment and aging treatment to precipitate 0.1 to 50% by volume of α phase in austenite (β) phase And a heat treatment step for obtaining
(A) Thermomechanical treatment (cold working + annealing)
The Cu-Al-Mn-Ni alloy having the above composition is melt cast and formed into a desired shape by a processing method such as hot working, cold working, pressing, etc. It is desirable to perform cold working such as cold rolling or cold drawing. By performing cold working a plurality of times, a wire, plate, pipe, or the like having austenite (β) single-phase crystal orientation aligned in the working direction can be obtained. Moreover, the orientation of the crystal orientation of the austenite (β) single phase can be improved by performing the β single phase treatment at least once, preferably twice or more after the cold working.

In order to increase the crystal orientation, it is better to increase the cold working rate of the cold working. In particular, the total processing rate after final annealing is preferably 30% or more. Taking a case where cold working and annealing are repeated several times as an example, the cold working rate is expressed by (t ₀ −t ₁ ) / t ₀ × 100 (%), and t ₀ : plate thickness before cold working, t ₁ : plate thickness after cold working.

  The existence frequency of the crystal orientation of the crystal structure measured by the electron backscattering pattern method or the X-ray diffraction method (representing the degree of alignment of the crystal orientation) is 2.0 or more in the processing direction, preferably 2.5 or more. is there. The crystal orientation frequency f (g) is expressed by the following formula: f (g) · V = dV / dg (where V is the volume of all crystal grains, g is the crystal orientation, and dV / dg is the crystal This is the volume of crystal grains contained in the minute orientation space dg in the orientation g). For example, the presence frequency of <110> in the processing direction is “0” when there is no processing direction, and “1” when the crystal orientation is completely random, and is completely aligned with the processing direction. The case is represented by “∞”, which is represented by a ratio in which the <110> crystal orientation exists in the processing direction. As the value of the crystal orientation existence frequency is larger, the crystal orientation is aligned in a specific direction. When the presence frequency of the crystal orientation in the processing direction is less than 2.0, the copper-based alloy does not have excellent shape memory characteristics and superelasticity.

  In order to make the austenite (β) single phase crystal orientation frequency in the processing direction 2.0 or more, for example, Cu 80.3% by mass, Al 8.1% by mass, Mn 8.5% by mass, Ni 3.1% by mass In the case of the vibration damping material having the composition, when the cold working and annealing are repeated several times to cold work the plate material, the total working rate after the final annealing is preferably 30% or more. If the total processing rate is less than 30%, the crystal orientation of the alloy structure is not uniform and excellent vibration damping cannot be obtained. More preferably, it is 50% or more.

  The cold working is preferably performed after the Cu—Al—Mn—Ni alloy is made into a crystal structure in which an α phase exists. By the presence of the α phase having good workability, a high cold working rate can be realized, and thereby the crystal orientation is easily aligned. The Cu—Al—Mn—Ni alloy to be cold worked preferably has an α phase volume fraction of 50% by volume or more. Specifically, the crystal structure in which the α phase exists is a β + α two-phase structure, and can be obtained by annealing treatment. The annealing treatment condition is a heating temperature of 450 to 800 ° C., and cooling after the annealing treatment may be air cooling. Outside this heating temperature range, the α phase does not sufficiently precipitate.

For a Cu—Al—Mn—Ni alloy, the processing rate obtained by one cold processing is 20% or less at most, so it is necessary to perform cold processing a plurality of times in order to obtain a high processing rate. . In that case, an annealing treatment is performed before cold working to obtain a crystal structure in which an α phase exists. Thus, by repeating the cycle consisting of multiple times of cold working and annealing treatment two or more times, it can be formed into a desired shape, but at least the cold working rate after final annealing should be 30% or more. Thus, high strength and excellent vibration damping properties can be obtained.
(B) β single-phase treatment β single-phase treatment is a heat treatment in which a cold-worked crude material is heated to a temperature range that becomes an austenite (β) single phase, and the crystal structure is transformed into an austenite (β) single phase. is there.

  It is desirable to maintain the β single phase treatment after cold working at a heating temperature of 800 ° C. or more for 0.1 to 20 minutes. The austenite (β) single phase temperature is approximately 800 to 950 ° C., although it varies depending on the alloy composition. Further, the holding time in this temperature range may be 0.1 minutes or more, and it is usually preferably less than 20 minutes in consideration of the influence of oxidation. However, since the crystal grains tend to grow and become coarse as the holding time increases, in order to obtain fine crystal grains, the shorter holding time is desirable and less than 2 minutes is preferable. More preferably, it is less than 1 minute.

The austenite (β) single phase state is frozen by rapidly cooling the Cu—Al—Mn—Ni alloy after the β single phase treatment. The rapid cooling can be performed by putting it in a refrigerant such as water, or by mist cooling or forced air cooling. If the cooling rate is low, the α phase is precipitated, and the austenite (β) single phase structure cannot be maintained. The cooling rate is desirably 200 ° C./sec or more, and more preferably 230 to 10000 ° C./sec.
(C) (β + α) two-phase treatment (β + α) two-phase treatment is performed by heating a cold-worked crude material to a temperature range that becomes (β + α) two phases or (β) a temperature range that becomes a single phase. This is a heat treatment that transforms the crystal structure into a (β + α) 2 phase by cooling.

  The (β + α) biphasic treatment after cold working is desirably held at a heating temperature of 500 ° C. or more for 0.1 to 30 minutes. The (β + α) two-phase temperature varies depending on the alloy composition, but is generally 800 ° C. or lower, preferably 600 to 800 ° C. In addition, the holding time in this temperature range may be 0.1 minutes or longer, and it is usually preferably less than 30 minutes in consideration of the influence of oxidation. As the retention time increases, the volume fraction of the α phase precipitated in the (β) phase increases. Therefore, heat treatment materials containing α phases having various volume fractions can be obtained by changing the retention time.

The (β + α) two-phase state is frozen by rapidly cooling the Cu—Al—Mn—Ni alloy after the (β + α) biphasic treatment. The rapid cooling can be performed by putting it in a refrigerant such as water, or by mist cooling or forced air cooling. The cooling rate is desirably 200 ° C./sec or more, and more preferably 230 to 10000 ° C./sec.
Further, by cooling the Cu—Al—Mn—Ni alloy to room temperature at an appropriate cooling rate such as air cooling after the (β) single phase treatment, the α phase is precipitated in the austenite (β) phase (β + α ) A two-phase state can be obtained. The cooling rate at this time is preferably less than 200 ° C./sec.
(D) Aging treatment It is preferable to perform an aging treatment after quenching. The aging temperature is less than 300 ° C, preferably 100 to 250 ° C. If the aging treatment temperature is too low, the austenite (β) phase is unstable, and if left at room temperature, the martensitic transformation temperature may change. On the contrary, if the aging temperature exceeds 250 ° C., bainite transformation occurs and becomes brittle.

The aging treatment time varies depending on the alloy composition, but is preferably 1 to 300 minutes, more preferably 5 to 200 minutes. If the aging treatment time is less than 1 minute, sufficient aging effect cannot be obtained, and if it exceeds 300 minutes, bainite transformation occurs and becomes brittle.
(E) Strain imparting In order to improve the damping property, it is preferable to impart a permanent strain to the damping material subjected to the aging treatment. The strain imparting method can be wire drawing, rolling, shot peening, or the like.

  When the permanent strain is applied by wire drawing or rolling, the processing rate is desirably 1 to 8%. If the processing rate is less than 1%, the effect of improving the vibration damping property by applying the strain is not recognized. On the other hand, if it exceeds 8%, the damping capacity is lowered, which is not preferable. More preferably, it is 2 to 5%.

Usually, shot peening is a processing method that improves the fatigue strength of the spring by hitting a small metal ball or cut wire on the surface of the spring at a high speed to generate compressive residual stress on the spring surface. It is a process applied accordingly. In the present invention, shot peening is suitably performed using a shot having a particle size of 100 μm or more and a shot speed of 30 to 80 m / sec. If shot peening is too weak, the effect of imparting strain is not recognized. On the other hand, if the strength is too strong, the damping capacity is lowered, which is not preferable.
(F) Superplasticity The vibration damping material of the present invention can exhibit superplastic properties in the temperature range of 350 to 600 ° C. In order to obtain such superplastic characteristics, cold working and annealing are repeatedly performed in the state of β + α two-phase structure in the above-described heat treatment, and the heat treatment after the cold work is replaced with the above solution treatment. Perform at low temperature.

  It is preferable that annealing is performed with a total cold working rate of about 30 to 80%, and this cold working + annealing cycle is repeated. If the cold working rate is less than 30%, fine crystal grains cannot be obtained, and if it exceeds 80%, cracks may occur, which is not preferable.

  The heat treatment after processing is preferably performed at a heating temperature of 400 to 800 ° C. for a holding time of 5 to 60 minutes. If the heat treatment temperature is less than 400 ° C., a recrystallized structure cannot be obtained, and if it exceeds 800 ° C., the crystal grains are coarsened. A more preferable temperature is 500 to 600 ° C. Further, if the holding time is less than 5 minutes, a (β + α) two-phase recrystallized structure in which a superplastic phenomenon occurs cannot be obtained, and if it exceeds 60 minutes, the crystal grains may be coarsened.

As described above, an ultrafine crystal grain structure of 10 μm or less can be obtained, and superplastic characteristics can be exhibited in a temperature range of 350 to 600 ° C.
(Crystal structure)
The vibration damping material of the present invention substantially consists of an austenite (β) single phase, and the crystal orientation of <110>, <100>, etc. of the austenite (β) single phase is aligned with the cold working direction such as rolling or wire drawing. It has a recrystallized structure. The existence frequency of the crystal orientation of the crystal structure measured by the electron backscattering pattern method or the X-ray diffraction method is 2.0 or more in the processing direction, preferably 2.5 or more. As the value of the crystal orientation existence frequency is larger, the crystal orientation is aligned in a specific direction. If the frequency of the crystal orientation in the processing direction is less than 2.0, the vibration damping material does not have excellent vibration damping properties.

  In addition, the relative crystal grain size d / w of the austenite (β) phase in the plate material is preferably 0.001 to 5. If d / w is less than 0.001, the vibration damping property is low. On the other hand, if d / w exceeds 5, the strength decreases, which is not preferable. The relative crystal grain size in the plate material is defined as the ratio between the crystal grain size and the plate width. If d / w is defined, the relative crystal grain size relative to other sample shapes, for example, d / t (t: plate This is because the thickness is also determined. The relative crystal grain size d / D of the austenite (β) phase in the wire is preferably 0.005 to 10. If d / D is less than 0.005, the vibration damping property is low. On the other hand, if d / D is more than 10, the strength decreases, which is not preferable.

  In the vibration damping material of the present invention, it is desirable that 50% or more of the volume fraction of the austenite (β) phase is transformed into the martensite (M) phase.

  The Cu—Al—Mn—Ni alloy exhibits excellent vibration damping properties even in the austenite (β) single phase, but the damping characteristics can be further improved by applying permanent strain. In other words, the martensite (M) phase generated by processing exhibits the effect of further improving the vibration damping properties, and if the volume fraction is less than 50%, the effect of improving the vibration damping properties is small. Preferably it is 60% or more.

  Furthermore, in the vibration damping material of the present invention, the structure is preferably a two-phase structure having an α phase in the recrystallized structure of austenite (β). By precipitating α phase in the recrystallized structure of austenite (β) by thermomechanical treatment, the strength and fatigue characteristics of the vibration damping material can be improved. In this case, in order to make the crystal grain size in the (β + α) two-phase structure fine, the heat treatment temperature is preferably set to 700 ° C. or lower. A remarkable improvement in fatigue properties can be expected when the crystal grain size is 30 μm or less.

The damping material having such a crystal structure desirably has a tensile strength at room temperature of 300 to 1200 MPa. If the tensile strength is less than 300 MPa, it is not suitable as a high-strength vibration damping material, and if it exceeds 1200 MPa, the vibration damping performance is significantly lowered.
(Spring with excellent vibration control)
The vibration damping material of the present invention is suitable for use in various springs. For example, a knit mesh spring or metal wire that is used to hold a ceramic carrier in a catalyst device or to be used as an anti-vibration cushioning material that absorbs vibrations. Examples of the coil spring include a coil spring, a spring washer used for bolt tightening and screw tightening, a thin plate spring that eliminates vibrations such as chatter, and a clamp spring.

  Among these springs, in particular, in a thin plate spring or a clamp spring made of a plate material, it is desirable to use a 45 ° direction as the longitudinal direction of the spring with respect to the rolling direction of the plate-shaped damping material. The characteristics of the plate-like spring obtained by rolling differ depending on the angle with respect to the rolling direction. For example, as shown in FIG. 5, in a low temperature tensile test at −100 ° C., a large elongation can be obtained with a low stress in the 45 ° direction relative to the rolling direction.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.
(Sample adjustment)
(Example 1)
An alloy containing Al: 8.0% by mass, Mn: 9.5% by mass, and Ni: 2.1% by mass with the balance being Cu and inevitable impurities is solidified by high-frequency melting in an argon atmosphere, and the cross section is A square member of 30 mm × 20 mm was produced. Subsequently, it is hot-rolled to a thickness of 2 mm at 800 ° C., and a cycle consisting of 600 ° C. × 10 minutes + air-cooled annealing and cold rolling is repeated several times to obtain a length of 300 mm, a width of 50 mm, and a thickness of 0.2 to 0 A plate material of 25 mm was obtained. Cold rolling and annealing were set to 2 mm → annealing → 1 mm → annealing → 0.5 mm → annealing → 0.25 (0.2) mm.

  From the obtained plate material, a sample having a length of 40 mm, a width of 1.0 to 1.4 mm, a distance between gauge points of 20 mm, and a thickness of 0.2 to 0.25 mm was cut out by electric discharge machining, and polished paper. The surface was polished. The sample collection direction was 0 °, 22.5 °, 45 °, 67.5 °, and 90 ° with respect to the rolling direction, and an appropriate number of samples were prepared.

Each surface-polished sample was subjected to a solution treatment at 900 ° C. for 15 minutes, then poured into water and rapidly cooled, and then subjected to an aging treatment at 200 ° C. for 15 minutes.
(Example 2)
The alloy composition was the same as in Example 1 except that the alloy composition was Al: 8.1% by mass, Mn: 8.5% by mass, and Ni: 3.1% by mass, with the balance being Cu and inevitable impurities. A sample was prepared.
(Example 3)
The alloy composition was the same as in Example 1 except that the alloy composition was Al: 8.3% by mass, Mn: 9.8% by mass, and Ni: 1.0% by mass, with the balance being Cu and inevitable impurities. A sample was prepared.
Example 4
The alloy composition was the same as in Example 1 except that the alloy composition was Al: 8.6% by mass, Mn: 9.8% by mass, and Ni: 0.4% by mass, with the balance being Cu and inevitable impurities. A sample was prepared.
(Example 5)
The alloy composition was the same as in Example 1 except that the alloy composition was Al: 8.2% by mass, Mn: 8.1% by mass, and Ni: 2.1% by mass, with the balance being Cu and inevitable impurities. A sample was prepared.
(Example 6)
The alloy composition is Al: 8.1% by mass, Mn: 8.5% by mass, Ni: 3.1% by mass and B: 0.04% by mass, and the balance is Cu and inevitable impurities. Before the crystallization treatment, the same treatment as in Example 1 was performed. After a solution treatment at 900 ° C. for 1 minute, the solution was poured into water and rapidly cooled, and then an aging treatment at 200 ° C. for 15 minutes was performed.
(Example 7) The same Ni: 3.1 mass% containing alloy as Example 2 is used, and it carries out similarly to Example 1 until hot rolling, and the heat processing after annealing (annealing + cold drawing) ) Was performed as follows with a reduction in area of 50%.

  That is, annealing → φ2 mm → annealing → φ1.4 mm → annealing → φ1.0 mm → annealing → φ0.7 mm → annealing → φ0.5 mm.

A sample having a length of 40 mm was cut out from the obtained wire having a diameter of 0.5 mm, and the surface was polished with polishing paper. Next, the surface-polished sample was subjected to a solution treatment at 900 ° C. for 15 minutes, then poured into water and rapidly cooled, and then subjected to an aging treatment at 200 ° C. for 15 minutes.
(Example 8)
The same Ni: 3.1 mass% containing alloy as Example 2 is used, and it has a superplastic characteristic by making a crystal grain into 10 micrometers or less.

  That is, a hot-rolled sheet having a thickness of 5 mm was produced by the same method as in Example 2 until hot rolling, and the heat treatment after annealing (annealing + cold working) was performed as follows, and the thickness was 1 mm. A rolled material was obtained. Annealing → 5 mm → annealing → 3 mm → annealing → 1.8 mm → annealing → 1 mm.

An appropriate number of samples having the shape shown in FIG. 11 were cut out from the obtained plate material and surface-polished with abrasive paper. The surface-polished sample was heat-treated at 600 ° C. for 30 minutes and air-cooled.
(Comparative Example 1)
A sample was prepared in the same manner as in Example 1, except that the alloy composition was Al: 8.1% by mass, Mn: 10.7% by mass, and the balance was Cu and inevitable impurities. did.
(Comparative Example 2)
Except that the alloy composition was Al: 8.6% by mass, Mn: 9.8% by mass, and Ni: 0.2% by mass, with the balance being Cu and inevitable impurities, the same as in Example 1. A sample was prepared.
(Comparative Example 3)
A sample was prepared in the same manner as in Example 5 using the same alloy as in Comparative Example 1.
(Comparative Example 4)
A sample was prepared in the same manner as in Example 1 except that the alloy composition did not contain Ni and was Al: 8.1% by mass, Mn: 9.7% by mass, and the balance was Cu and inevitable impurities. did.
(Comparative Example 5)
Example except that the alloy composition does not contain Ni and is Al: 8.1% by mass, Mn: 9.7% by mass, B: 0.04% by mass, and the balance is Cu and inevitable impurities. A sample was prepared in the same manner as in Example 4.
(Test method)
(1) Measurement of electron backscattering pattern Using an electronic backscattering pattern measuring apparatus (trade name: Orientation Imaging Microscope, manufactured by TSL), the austenite (β) phase in the rolling direction or the drawing direction of the obtained sample. The existence frequency of the crystal orientation was measured. FIG. 9 shows a reverse pole figure and a pole figure showing the frequency of existence of crystal orientations by contour lines, (a) obtained for the plate material of Example 2 and (b) the wire material of Example 7.

In the reverse pole figure of FIG. 9, it can be seen that in both Example 2 and Example 7, the contour lines are gathered in the <110> direction, and the <110> direction is aligned in the rolling direction (or wire drawing direction). Furthermore, from the pole figure, in Example 2 (sheet material) of (a), it is understood that the [112] direction is aligned in the direction perpendicular to the rolling surface, and a {112} <110> texture is formed. . On the other hand, in Example 7 (wire) of (b), it can be seen that the fiber texture is aligned in the [110] direction, and the crystal orientation is randomly oriented in the sample cross section.
(2) Damping ability characteristic The damping ability (tan Φ) of the obtained sample was measured using a viscoelasticity measuring device (DMS: Dynamic Mechanical Spectrometer manufactured by Seiko Denshi Kogyo Co., Ltd.). The measurement conditions were strain mode: 5 × 10 ⁻⁴ , frequency: 1 Hz tensile mode, and heating / cooling rate: 2 ° C./min.
(3) Mechanical properties The mechanical properties of the obtained samples were measured using a tensile tester (manufactured by Orientec).

The tensile conditions were a distance between the gauge points of 20 mm and a tensile speed of 0.5 mm / min (crosshead speed). The test temperature was set at two levels of −100 ° C. and room temperature depending on the sample.
(4) Crystal grain size The surface of each sample was polished, etched with a ferric chloride aqueous solution, and a structure photograph was taken with a metal microscope. The crystal grain size d was obtained as d = L / N by drawing a straight line having an arbitrary length L on the obtained structure photograph and counting the number N of crystal grain boundaries on the straight line.
(5) Superplastic properties Using a tensile tester (manufactured by SHIMADZU), the obtained samples were pulled at high temperature to measure the superplastic properties.

The tensile test temperature was set to two levels of 450 ° C. and 500 ° C., and the tensile speed (crosshead speed) was set to four levels in the range of 0.15 to 30 mm / min. These four levels are the speeds corresponding to the strain rate between the specimens of the sample of 5 × 10 ⁻⁴ / s, 2 × 10 ⁻³ / s, 1 × 10 ⁻² / s, and 1 × 10 ⁻¹ / s. is there.
(Test results)
The results will be described below with reference to the drawings.
(1) Damping characteristics FIG. 1 shows changes in damping capacity (tan Φ) with temperature. FIG. 1 also shows the results of Example 1, Example 2, and Comparative Example 1. The damping capacity shows hysteresis which is a different route between temperature rise and temperature fall in the same temperature range. For example, in Example 1, it changes along the arrow depending on the temperature. And the peaks P1 and P2 of damping ability are produced on the high temperature side and the low temperature side. The peak P1 on the high temperature side is generated by the reverse transformation of the martensite (M) phase to the austenite (β) phase, and the peak P2 on the low temperature side is caused by the transformation of the austenite (β) phase to the martensite (M) phase. It will occur. The example containing Ni shows a high peak compared to the comparative example, and the damping ability in the martensite (M) phase is also shifted to the high damping ability side as a whole.

  FIG. 2 shows the damping capacity at −100 ° C. in relation to the Ni content. That is, the attenuation ability at −100 ° C. of each sample in FIG. 1 is plotted. The damping material is completely transformed into a martensite (M) phase at −100 ° C., and in Comparative Example 1 containing no Ni, the damping capacity is as low as about 0.05. However, the damping ability is improved by containing Ni, and when Ni of Example 1 is contained by 2.1% by mass, it shows an excellent damping ability of 0.12, which is twice or more that of Comparative Example 1. It was.

  In addition, the relative crystal grain diameter of each sample was substantially the same, d / w was 0.3-0.4, and d / t was 2-3. Here, w is the width of the sample, and t is the thickness of the sample.

  Since the vibration damping material of the present invention has a crystal structure in which the crystal orientation of the material is aligned in the rolling direction in the plate material, the damping capacity also varies depending on the sample collecting direction. FIG. 3 shows the relationship between the angle with respect to the rolling direction and the damping capacity for Example 2. In addition, the attenuation capability of FIG. 3 is a value in -100 degreeC. Since Example 2 forms a {112} <110> texture as described above, the crystal orientation in the sample collection direction changes as shown in the direction of the DMS test direction along the X axis in the figure. In Example 2, it can be seen that the damping ability in the direction of 45 ° is the highest with respect to the rolling direction and the damping ability in the direction perpendicular to the rolling direction is low. However, since the crystal orientation is strongly oriented in a specific direction, the damping ability is superior to that of Comparative Example 1 in all test directions.

  FIG. 4 shows the change in damping capacity (tan Φ) with temperature in Example 5. That is, it is a result of a sample having a martensite (M) phase at room temperature using an alloy containing 2.1% by mass of Ni as in Example 1. The relative crystal grain size of Example 5 was almost the same as that of Example 1. In Example 5, the peaks P1 and P2 are both moved to the high temperature side as compared to Example 1, but it can be seen that the Example 5 has a high attenuation capacity equivalent to that of Example 1.

FIG. 5 shows the change in damping capacity (tan Φ) with temperature in the wire. FIG. 5 also shows the results of Example 7 and Comparative Example 3. The relative crystal grain size d / D of Example 7 and Comparative Example 3 was 0.4 to 0.5. Here, d is the crystal grain size, and D is the diameter of the wire. In Example 7 containing Ni in comparison with Comparative Example 3 containing no Ni, the fiber texture is aligned in the wire drawing direction by wire drawing, so excellent attenuation even when the crystal orientation in the sample cross section is in a random state It turns out that it shows the ability.
(2) Mechanical properties FIG. 6 shows the results of a tensile test performed at −100 ° C. for each sample collected at an angle with respect to the rolling direction of Example 2. As can be seen from FIG. 6, the tensile strength is highest in the 90 ° direction and lowest in the 45 ° direction with respect to the rolling direction. Further, the 45 ° direction is the largest in the rolling direction, and the 45 ° direction has an elongation of 4 to 5 times that of the 90 ° direction at the same tensile strength. That is, it can be seen that at -100 °, the 45 ° direction is most easily formed relative to the rolling direction.

  FIG. 7 shows the result of a tensile test performed on Example 5 at room temperature. Also in this case, the strength is low and the elongation is large in the direction of 45 ° than in the direction parallel to the rolling direction.

The above results are plotted in relation to tensile strength and damping capacity and are shown in FIG. In FIG. 8, (●) is Example 5 and (◇) is Example 2, each plot is shown as an ellipse for each example, and Example 6 (♦) is also shown. In Comparative Example 4 and Comparative Example 5, ◯ and ■ are described together, but ○ is data for a single phase of austenite (β), and ■ is data for a two-phase structure of α + β. is there. As is clear from FIG. 8, Example 2 and Example 5 have higher damping ability than Comparative Example 4 and Comparative Example 5. Further, the crystal grain size was refined by adding B (relative crystal grain size: d / w = 0.05, d / t = 0.3, where d is the crystal grain size and w is the width of the sample. , T is the thickness of the sample.) It can be seen that Example 6 has high strength and good damping capacity.
(3) Superplastic properties Each sample obtained in Example 8 was pulled at various strain rates under heating conditions of 450 ° C. and 500 ° C., and the superplastic properties were confirmed. FIG. 12 shows a tensile test result when the heating condition is 500 ° C. Although the strain rate was set to 4 levels, it can be seen that a large elongation can be obtained with a low stress as the strain rate decreases. In particular, at 5 × 10 ⁻⁴ with the slowest strain rate, it was possible to obtain an elongation of 1000% or more simply by applying a stress of 10 MPa or less. The results are shown in Table 1.

ここで、歪み速度と応力のピーク値（図１２にσｐで示す）との関係を両対数グラフで図１３に示す。図１３の△は４５０℃加熱の場合であり、◆は５００℃加熱の場合を示す。両者の関係はほぼ直線となり、その勾配（ｍ値）は、４５０℃、および５００℃のいずれにおいても超塑性現象を示しているとされる０．３〜１の範囲であり、４５０℃では歪み速度が１×１０^-2／ｓ以下で、また、５００℃では歪み速度が１×１０^-1／ｓ以下で超塑性特性を発現することが確認された。すなわち、Ｎｉ３．１質量％を含有する銅系合金では１×１０^-1／ｓという極めて早い歪み速度でも超塑性特性を発揮することができるので、高速でかつ精密な鍛造、加工を極めて容易に施すことができる。
（４）板バネ
（供試材１）
本発明のＣｕ−Ａｌ−Ｍｎ−Ｎｉ合金からなる板バネである。

Here, the relationship between the strain rate and the peak value of stress (indicated by σp in FIG. 12) is shown in a log-log graph in FIG. In FIG. 13, Δ indicates the case of 450 ° C. heating, and ◆ indicates the case of 500 ° C. heating. The relationship between the two is almost a straight line, and the gradient (m value) is in the range of 0.3 to 1, which is considered to indicate a superplastic phenomenon at both 450 ° C. and 500 ° C. It was confirmed that superplastic properties were exhibited when the speed was 1 × 10 ⁻² / s or less and at 500 ° C., the strain rate was 1 × 10 ⁻¹ / s or less. In other words, a copper-based alloy containing 3.1% by mass of Ni can exhibit superplastic characteristics even at an extremely high strain rate of 1 × 10 ^-1 / s, so that high-speed and precise forging and processing are extremely easy. Can be applied.
(4) Leaf spring (sample 1)
It is a leaf | plate spring which consists of a Cu-Al-Mn-Ni alloy of this invention.

  An alloy comprising Al: 8.3 mass%, Mn: 8.0 mass%, and Ni: 2.1 mass%, the balance being Cu and inevitable impurities, is solidified by high-frequency melting in an argon atmosphere, and the cross section A square member of 20 mm × 30 mm was produced. Subsequently, hot rolling was performed at 800 ° C. to obtain a square member having a cross section of 10 mm × 10 mm. The hot-rolled square was subjected to a heat treatment of 600 ° C. × 10 minutes + air-cooled annealing and cold rolling to obtain a plate having a thickness of 1 mm × width 20 mm × length 250 mm. The cold rolling and annealing were performed as 10 mm → annealing → 5 mm → annealing → 2.5 mm → annealing → 1 mm.

  The obtained plate material was subjected to a β-single phase treatment at 900 ° C. for 15 minutes, and then poured into water to quench, and then subjected to an aging treatment at 200 ° C. for 15 minutes to obtain a test material 1.

Specimen 1 had a martensite transformation start temperature (Ms) of 40 ° C., a martensite reverse transformation end temperature (Af) of 70 ° C., and was in a martensite (M) phase at room temperature (15 ° C.). The relative crystal grain size d / w was 0.2 to 0.3.
(Sample 2)
It is a leaf spring made of a conventional copper alloy. Thickness 1 mm × width 20 mm × length 250 mm, except that the alloy composition was Al: 8.1 mass%, Mn: 9.7 mass%, and V: 0.45 mass%. Sample 2 was obtained.

Test material 2 had a martensite transformation start temperature (Ms) of 40 ° C., a martensite reverse transformation end temperature (Af) of 70 ° C., and was in a martensite (M) phase at room temperature (15 ° C.). The relative crystal grain size d / w was 0.2 to 0.3.
(Sample 3)
It is SUS310 conventionally used. SUS310-3 / 4H having a thickness of 1 mm, a width of 20 mm, and a length of 250 mm was used as test material 3.

  For the above three types of test materials, the frequency response function is obtained by the central support steady excitation method specified in JIS G0602 “Vibration damping characteristic test method of damping steel plate”, and the loss factor is calculated using the half width method. did. The measurement was performed using an electromagnetic shaker manufactured by IMV at a temperature of 15 ° C. and an excitation force of 1 G. The results are shown in FIG.

  FIG. 14 shows both the loss factor (η) at the primary resonance frequency of each specimen and the loss factor (η) at the secondary resonance frequency. The numerical values in the figure are the resonance frequencies of the specimens. is there.

  Specimen 1 and Specimen 2 have a martensite (M) phase at the measurement temperature (15 ° C.). The specimen 1 of the present invention has a higher loss factor (η) for both the primary resonance and the secondary resonance than the specimen 2 and specimen 3, and the loss factor of the primary resonance is particularly the It is about 2.4 times that of the specimen 3. In addition, the loss factor at the time of the primary resonance of the test material 2 and the test material 3 is almost equal because the conventional copper-based alloy cannot obtain good vibration characteristics unless the crystal grain size is increased. This is because the crystal grain size of the test material 2 is as fine as a relative crystal grain size of 0.2 to 0.3.

  A spring having excellent vibration damping properties such as a knit mesh spring, a coil spring, and a thin plate spring made of the vibration damping material of the present invention is used as, for example, an anti-vibration cushioning material for preventing the occurrence of a booming sound in an automobile, and a car audio system. It can be suitably used for eliminating chattering noises by using it for mounting.

  In addition, since the vibration damping material of the present invention has superplastic properties, it can manufacture parts with complex shapes, such as home appliances, automobiles, and water-related parts, at high speed and precision, contributing to improved productivity and quality. There is a lot to do.

4 is a graph showing a change in damping capacity (tan Φ) depending on a temperature of a damping characteristic, and shows Example 1, Example 2, and Comparative Example 1. FIG. It is a graph which shows the relationship between Ni content and damping ability in -100 degreeC. It is a graph which shows the relationship between the test direction with respect to the rolling direction of Example 2, and damping capacity. It is a graph which shows the change of the damping capacity by the temperature of a Ni2.1 mass% containing alloy (Example 3) which has a martensite (M) phase at room temperature. It is a graph which shows the change of the attenuation capability by the temperature of Example 7 which is a wire. It is a graph which shows the low-temperature (-100 degreeC) tension test result of Example 2, and writes together the result of each angle direction with respect to a rolling direction. It is a graph which shows the test result which carried out the tension test at room temperature about Example 5. FIG. It is the figure which plotted each test result by the relationship between tensile strength and damping ability. It is a reverse pole figure and pole figure which show crystal orientation. (A) is a measurement result of Example 2 (plate material), (b) shows the measurement result of Example 7 (wire material). It is a figure which shows the relationship between the tensile strength of various materials, and logarithmic attenuation factor (delta) ((pi) tan (PHI)). It is a figure which shows the test piece shape of the high temperature tensile test which measures a superplastic characteristic. It is a graph which shows the tension test result in Example 8 at 500 degreeC. It is a logarithmic graph showing the relationship between the peak value of stress (σp) and the strain rate. It is a bar graph which compares each loss coefficient ((eta)) of the test materials 1-3.

Claims (16)

  In terms of mass percentage, when 3 to 10% Al, 5 to 20% Mn, 0.2 to 10% Ni, and the whole alloy as 100%, 0.001 to 10% Co in total, At least one element selected from the group consisting of Fe, Ti, V, Cr, Si, Nb, Mo, W, Sn, Sb, Mg, P, Be, Zr, Zn, B, C, Ag, and Misch metal; A damping material comprising a Cu—Al—Mn—Ni alloy with the balance being Cu and inevitable impurities.   2. The vibration damping material according to claim 1, wherein the Cu—Al—Mn—Ni alloy has a recrystallized structure composed of an austenite (β) single phase whose crystal orientation is aligned by a thermomechanical treatment.   The vibration damping material according to claim 1 or 2, wherein the austenite (β) single-phase crystal orientation measured by an electron backscattering pattern method has a presence frequency in the processing direction of 2.0 or more.   The vibration damping material according to claim 1, wherein 50% or more of the volume fraction of the austenite (β) phase is transformed into a martensite (M) phase.   The vibration damping material according to claim 2, which is a two-phase structure in which an α phase is precipitated in the recrystallized structure.   The vibration damping material according to claim 5, wherein the α phase is 0.1 to 50% by volume with 100% by volume as a whole.   The damping material according to any one of claims 2 to 6, wherein a crystal grain size d of the austenite (β) phase is 0.001 <d / w <5, where w is a plate width of the plate material.   The damping material according to any one of claims 2 to 6, wherein a crystal grain size d of the austenite (β) phase is 0.005 <d / D <10, where D is a wire diameter of the wire.   The damping material according to any one of claims 1 to 7, wherein the tensile strength at room temperature is 300 to 1200 MPa.   The damping material according to claim 1, which exhibits a superplastic phenomenon at 350 to 600 ° C.   The vibration damping material according to claim 10, wherein the crystal grain size is 10 μm or less.   An ingot forming process in which raw materials containing Cu, Al, Mn, and Ni as main components are prepared and melted to form an ingot, and the ingot is subjected to hot working, followed by cold heat treatment and annealing. A rough material forming step for obtaining a rough material of a predetermined size, and a heat treatment step for obtaining a heat treatment material in which the coarse material is subjected to β single phase treatment, quenching treatment and aging treatment to fix an austenite (β) phase. A method for producing a vibration damping material characterized by the above.   An ingot forming process in which raw materials containing Cu, Al, Mn, and Ni as main components are prepared and melted to form an ingot, and the ingot is subjected to hot working, followed by cold heat treatment and annealing. A coarse material forming step for obtaining a coarse material of a predetermined size, and this coarse material is subjected to (β + α) biphasic treatment, quenching treatment and aging treatment to precipitate 0.1 to 50% by volume of α in the austenite (β) phase. And a heat treatment step for obtaining a heat treated material.   The method of manufacturing a damping material according to claim 12 or 13, wherein the total heat treatment after the final annealing is 30% or more in the heat treatment in the coarse material forming step.   The manufacturing method of the damping material in any one of Claims 12-14 which further has the distortion provision process which provides a permanent strain to the said heat processing material.   The method for producing a vibration damping material according to claim 15, wherein the strain applying step is any one of wire drawing, rolling, and shot peening.

Images