JP2002372151A - Diaphragm and diaphragm valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diaphragm valve with a wide flow control range of fluid. SOLUTION: The diaphragm comprising an alloy composition with a Young's modulus of <=90 GPa and yield strength of >=100 MPa is used in the diaphragm valve.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a diaphragm and a diaphragm valve.

[0002]

2. Description of the Related Art A diaphragm means a flexible thin film, and is formed from various materials such as metal, plastic, and glass. Known products using a diaphragm include a diaphragm valve, a diaphragm pump, a diaphragm compressor, and a diaphragm pressure gauge.

[0003] A diaphragm valve is a valve that controls the flow rate of a fluid by utilizing the elastic deformation of the diaphragm. There are two types of diaphragm valves: one that opens and closes the valve by moving the valve lid by displacement due to elastic deformation of the diaphragm, and one that opens and closes the valve by displacement due to elastic deformation using the diaphragm itself as the lid of the valve. A diaphragm valve having a diaphragm as a valve cover has a fluid chamber in which two flow paths are connected, and a wall of the fluid chamber facing a connection between one of the flow paths and the fluid chamber is formed by the diaphragm. Then, a force is applied to the diaphragm from outside the fluid chamber to elastically deform the diaphragm, and the distance between the connection portion and the diaphragm is changed to control the flow rate of the fluid flowing through the flow path.
The diaphragm valve having such a structure is suitable for controlling the flow rate of a corrosive fluid because the fluid does not come into contact with a mechanical device that opens and closes the valve.

[0004] Diaphragm pumps are used to transfer fluids such as liquids and gases. The diaphragm pump includes a pump chamber provided with a suction valve and a discharge valve, and a part of a wall of the pump chamber is formed by the diaphragm. The inner volume of the container is repeatedly increased and decreased by applying a force to the diaphragm from the outside of the pump chamber by the driving means to elastically deform the diaphragm. When the internal volume of the pump chamber increases, the pressure inside the pump chamber decreases and the discharge valve is closed, and at the same time, the suction valve is opened and the fluid flows into the pump chamber. Next, when the internal volume of the pump chamber decreases, the pressure inside the pump chamber increases and the suction valve is closed, and at the same time, the discharge valve is opened and the fluid flows out of the pump chamber. In this way, the fluid can be transferred by repeatedly increasing and decreasing the inner volume of the pump chamber by utilizing the elastic deformation of the diaphragm. Further, the diaphragm pump can be used as a gas compressor by sucking gas from the suction valve of the diaphragm pump and utilizing compressed gas exhausted from the discharge valve.

[0005]

The diaphragm valve controls the flow rate of the fluid by utilizing the deformation of the diaphragm within the elastic limit. When subjected to a pressure exceeding the elastic limit, plastic deformation occurs in the diaphragm. If the diaphragm is plastically deformed, the flow rate may be set incorrectly, or the valve may not be closed sufficiently, causing fluid leakage. As described above, the diaphragm valve is used for controlling a fluid having a relatively small flow rate because the control range of the flow rate is limited by the physical properties (mechanical characteristics) of the material used for the diaphragm. In order to widen the flow control range of the diaphragm valve,
Consideration has been given to increasing the size of the valve and devising the structure of the flow path of the valve. A diaphragm valve in which the structure of the flow path is devised is described in JP-A-8-105554.

[0006] A diaphragm pump transfers fluid by increasing or decreasing the internal volume of a pump chamber provided with a suction valve and a discharge valve by utilizing deformation within the elastic limit of the diaphragm. The amount of fluid transferred in one cycle of the increase and decrease of the internal volume of the pump chamber means the transfer speed of the fluid, and is one of the important performances of the pump. The amount of fluid transferred in one cycle is
The difference between the maximum volume and the minimum volume of the pump chamber formed by the elastic deformation of the diaphragm, which is limited by the physical properties (mechanical properties) of the material used for the diaphragm. If the diaphragm is plastically deformed beyond the elastic limit, the fluid transfer speed of the pump may change or the diaphragm may be damaged. When a diaphragm pump is used as a gas compressor, the gas compression rate is limited by the physical properties (mechanical characteristics) of the diaphragm.

Conventionally, in order to widen the flow control range of the diaphragm valve or to increase the fluid transfer speed of the diaphragm pump, measures have been taken such as enlarging the valve or the pump or devising the structure. By forming the diaphragm from a material having excellent flexibility, the flow rate control range of the diaphragm valve and the fluid transfer speed of the diaphragm pump can be improved, but no sufficient study has been made. This is because the flow control range and the fluid transfer speed can be easily improved by increasing the size of the diaphragm valve or the diaphragm pump, rather than examining the material of the diaphragm in detail. In addition, diaphragm valves and diaphragm pumps
A diaphragm made of a metal material such as stainless steel is generally used from the viewpoint of corrosion resistance to a fluid. Increasing the size of the device in order to improve the flow control range of the diaphragm valve and the fluid transfer speed of the diaphragm pump is not always a preferred method.

An object of the present invention is to provide a diaphragm valve having a wide range of fluid flow control. Another object of the present invention is to provide a diaphragm pump having a high fluid transfer speed.

[0009]

Means for Solving the Problems As a result of intensive studies on the material forming the diaphragm, the present inventor has found that a diaphragm valve having a wide range of fluid flow control can be obtained by forming a diaphragm from an alloy composition having excellent flexibility. It has been found that a diaphragm pump having a high fluid transfer speed can be provided. The present invention resides in a diaphragm made of an alloy composition having a Young's modulus of 90 GPa or less and a yield strength of 100 MPa or more. Preferred embodiments of the diaphragm of the present invention will be described below.

(1) The alloy composition has a composition represented by the following formula. _{Ti 100-abcd M a M '} b M "c V d [ where, M represents, Zr, and one or both of Hf, M' is, Nb, and one or both of Ta, M" Is one or more elements selected from the group consisting of Cr, Mo, W, and Sn, and a, b, c,
And d is 5 ≦ a ≦ 40, 1 ≦ b ≦ 30, 0
≦ c ≦ 10, 0 ≦ d ≦ 20, 10 ≦ a + b + c + d ≦ 6
It is a numerical value that satisfies 0. ]

(2) The alloy composition further has a composition represented by the following formula. _{Ti 100-abcd Zr a M '} b M "c V d [ where, M' is, Nb, and one or both of Ta, M" is selected Cr, Mo, W, and from the group consisting of Sn One or more elements, a, b,
c and d are respectively 5 ≦ a ≦ 40, 1 ≦ b ≦ 3
0, 0 ≦ c ≦ 10, 0 ≦ d ≦ 20, 10 ≦ a + b + c +
It is a numerical value satisfying d ≦ 60. ]

[0012] The present invention also resides in a diaphragm valve provided with a diaphragm made of an alloy composition having a Young's modulus of 90 GPa or less and a yield strength of 100 MPa or more. Preferred embodiments of the diaphragm valve of the present invention will be described below. The preferred embodiment of the alloy composition is the same as that of the diaphragm of the present invention.

(1) An electromagnetic motor is installed on one surface of the diaphragm via a piezoelectric actuator. (2) A piezoelectric actuator is formed by laminating two or more piezoelectric elements. (3) The electromagnetic motor is a stepping motor.

Further, according to the present invention, the Young's modulus is 90 GP.
a and a diaphragm pump provided with a diaphragm made of an alloy composition having a yield strength of 100 MPa or more. The preferred embodiment of the alloy composition is the same as that of the diaphragm of the present invention.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Conventionally, in order to manufacture a diaphragm provided in a diaphragm valve or a diaphragm pump, as described above, corrosion resistance to a fluid is taken into consideration.
Corrosion-resistant metal materials such as stainless steel have been used. The present inventor has studied various metal materials such as aluminum having excellent corrosion resistance and small Young's modulus (excellent flexibility). However, metal materials with low Young's modulus often have low mechanical strength (yield strength, hardness, etc.),
It was found that the diaphragm may be plastically deformed by the force applied to the diaphragm. As described above, the plastic deformation generated in the diaphragm is not preferable because the performance of the valve or the pump is deteriorated. Table 1 shows the values of Young's modulus and yield strength of stainless steel conventionally used for diaphragms. Table 1 shows the values of Young's modulus and yield strength of aluminum as a typical example of a metal having a small Young's modulus.

[0016]

[Table 1]

As shown in Table 1, aluminum having a smaller Young's modulus than stainless steel has extremely low mechanical strength such as yield strength. The present inventor studied various metal materials having a small Young's modulus, but found no metal material suitable for the diaphragm.

In the present invention, the diaphragm is formed from an alloy composition having a low Young's modulus and a high yield strength. More specifically, the diaphragm has a Young's modulus of 90 GP.
a and is formed from an alloy composition having a yield strength of 100 MPa or more. An alloy composition having a yield strength of 100 MPa or more hardly undergoes plastic deformation due to a force applied to the diaphragm, and can be preferably used for a diaphragm valve, a diaphragm pump, and the like.

The Young's modulus of the alloy composition is preferably 80 GPa or less, more preferably 70 GPa or less, and even more preferably 60 GPa or less. However, if the Young's modulus is extremely small, the diaphragm may bend due to vibration in the operating environment, and the flow rate of the diaphragm valve may fluctuate, or the transfer speed of the fluid may fluctuate in the case of a diaphragm pump. Is preferably 40 GPa or more.

The yield strength of the alloy composition is preferably at least 250 MPa, more preferably at least 500 MPa. The yield strength is preferably as high as possible, but is generally 2000 MPa or less. By using a diaphragm made of an alloy composition that satisfies the above characteristics, the performance of a diaphragm valve or a diaphragm pump can be improved. The composition of the alloy forming the diaphragm is not particularly limited as long as the alloy has the above-mentioned properties.

The thickness of the diaphragm varies depending on the intended use, but is generally 1 mm or less. The diaphragm may be used alone, or two or more diaphragms may be used in an overlapping manner.

[0022] The alloy composition may be crystalline or amorphous. When the alloy composition is amorphous, the alloy composition may have a mixed phase structure in which a crystal phase having an average particle size of less than 1 μm is dispersed in the amorphous phase. An alloy composition containing an amorphous phase is obtained by quenching after melt-mixing each composition of the alloy composition. For quenching, a known method, for example, a single roll liquid quenching method, a twin roll liquid quenching method, a liquid casting method, or the like can be used. An alloy composition having such an amorphous phase,
It has the advantage of excellent mechanical strength with no specific slip band and excellent corrosion resistance due to the absence of grain boundaries.

The alloy composition may be subjected to a heat treatment in order to adjust the Young's modulus and the yield strength of the alloy composition forming the diaphragm. Examples of heat treatment of the alloy composition include quenching, tempering, annealing, normalizing, and aging treatments. The alloy composition may be subjected to hot working, cold working, or the like.

It is preferable that the alloy composition has a composition represented by the following formula. Ti _100-abcd M _a M '
_b M ″ _c V _d [where M is one or both of Zr and Hf, M ′ is one or both of Nb and Ta, and M ″ is Cr, Mo, W, And one or more elements selected from the group consisting of
b, c and d are respectively 5 ≦ a ≦ 40, 1 ≦ b ≦
30, 0 ≦ c ≦ 10, 0 ≦ d ≦ 20, 10 ≦ a + b + c
It is a numerical value satisfying + d ≦ 60. In order to finely adjust mechanical properties such as Young's modulus and yield strength, toughness, and corrosion resistance to desired levels, it is effective to add V, Cr, Mo, W, and Sn.

As a specific example of such an alloy composition, T
i₆₀Zr₂₀Ta_TenNb_Ten, Ti₅₀Zr₃₀Ta_TenNb_Ten,
Ti₅₅Zr_{twenty five}Ta_TenNb_Ten, Ti₅₅Zr₂₀Hf_FiveTa_Ten
Nb _TenTi₅₅Zr₃₀Nb_TenSn_Five, Ti₅₀Zr_{twenty five}Ta_Five
Nb_FiveV₁₅, Ti₆₀Zr₂₀Ta_FiveNb_TenCr_Five, Ti₆₀
Zr₂₀Ta_TenNb_FiveMo_Five, And Ti₅₅Zr₂₀Ta_TenN
b_TenW_FiveAnd the like. The illustrated alloy compositions are all
And the Young's modulus is 60 GPa or less and the yield strength is 6
More than 50MPa, especially as a material for diaphragm
It can be preferably used.

Next, the diaphragm valve will be described with reference to the accompanying drawings. FIG. 1 is a sectional view schematically showing a configuration of an example of the diaphragm valve of the present invention. In the diaphragm valve of the present invention, two flow paths 1 and 2 through which a fluid flows,
It is connected through the fluid chamber 3. A part of the fluid chamber 3 facing the connection between the flow path 1 and the fluid chamber 3 is formed by the diaphragm 4. A handle 6 is provided on a surface of the diaphragm outside the fluid chamber 3 via a valve rod 5. And one of the two flow paths 1
A valve seat 7 is provided at the connection between the fluid chamber. The configuration of such a diaphragm valve is well known. In the present invention, the diaphragm 4 provided in the diaphragm valve is
It is formed from the alloy composition described above.

By turning the handle 6 of the diaphragm valve, the valve stem 5 moves up and down, and the diaphragm 4 is elastically deformed. When the diaphragm 4 is elastically deformed, the distance between the diaphragm 4 and the valve seat 7 changes, so that the flow rate of the fluid flowing through the two flow paths can be controlled. Therefore, the diaphragm 4 is arranged such that the deformation when opening and closing the valve is within the elastic limit of the diaphragm. When the diaphragm is formed from the above-described alloy composition, the range of elastic deformation is wide, so that the distance between the diaphragm and the valve seat can be set large, and a diaphragm valve with a wide flow control range can be provided.

Next, another example of the diaphragm valve will be described. FIG. 2 is a diagram schematically showing the configuration of another example of the diaphragm of the present invention. The configuration of the diaphragm valve is the same as that of the diaphragm valve shown in FIG. FIG.
In the diaphragm valve shown in (1), an electromagnetic motor 9 is installed on a diaphragm surface outside the fluid chamber 3 via a piezoelectric actuator 8. The diaphragm is elastically deformed by the piezoelectric actuator 8 and the electromagnetic motor 9. The electromagnetic motor 8 is provided with a ball screw 11. By rotating the electromagnetic motor 8, the diaphragm 4 is elastically deformed by applying a vertical force to the diaphragm 4. Further, by slightly deforming the diaphragm 4 by the piezoelectric actuator 8, the flow rate can be accurately controlled over the entire flow rate control range of the diaphragm valve.

The piezoelectric actuator preferably comprises two or more piezoelectric elements. FIG. 2 illustrates a case where the piezoelectric actuator includes ten piezoelectric elements 10. In FIG. 2, only one of the ten piezoelectric elements is indicated by the reference numeral. Each of the ten piezoelectric elements 10 is provided with a driving device (not shown) for independently applying a voltage. Even if the displacement of one piezoelectric element is 1 μm, the displacement of the diaphragm can be finely adjusted within the range of 10 μm by arranging ten piezoelectric elements in an overlapping manner. Further, in order to accurately control the flow rate of the fluid, the electromagnetic motor that elastically deforms the diaphragm is preferably a stepping motor. By measuring the flow rate of the fluid flowing through the flow path and controlling the rotation amount of the electric motor and the driving of the piezoelectric element, the flow rate of the fluid flowing through the flow path can be accurately set. When the difference between the set value and the measured value of the flow rate is large, the diaphragm is deformed by the electric motor. It becomes possible.

Next, the diaphragm pump will be described. FIG. 3 is a diagram schematically showing a configuration of an example of the diaphragm pump of the present invention. The diaphragm pump of the present invention has a pump chamber 15 in which a part of a container 14 provided with a suction valve 12 and a discharge valve 13 is formed by the diaphragm 4.
And a driving means 16 for elastically deforming the diaphragm 4 to increase or decrease the internal volume of the pump chamber 15. The arrow shown in FIG. 3 indicates the direction in which the diaphragm 4 is elastically deformed by the driving means 16. The driving means 16 includes an electric transmitter 18 and a crankshaft 19. Rotational movement of the electric motor 18 is converted into vertical movement by the crankshaft 19, and the diaphragm is elastically deformed so that the pump chamber 1 is deformed.
5 is repeatedly increased or decreased. The configuration of the diaphragm pump shown in FIG. 3 is well known. In the present invention, the diaphragm 4 provided in the diaphragm pump is formed from the above-described alloy composition.

When the internal volume of the pump chamber 15 is increased by the driving means 16, the pressure inside the pump chamber 15 is reduced and the discharge valve 13 is closed, and at the same time, the suction valve 12 is opened and the fluid is introduced into the pump chamber 15. Flows in. Next, when the internal volume 15 of the pump chamber decreases, the pressure inside the pump chamber 15 increases and the suction valve 12 is closed, and at the same time, the discharge valve 13 is opened and the fluid flows out of the pump chamber 15. The fluid can be transferred by repeatedly changing the inner volume of the pump chamber 15 by elastically deforming the diaphragm 4 by the driving means 16. The amount of fluid transferred by one vertical movement of the driving means 16, that is, the fluid transfer speed of the pump is determined by the difference between the maximum volume and the minimum volume of the pump chamber within a range where the diaphragm can be elastically deformed. Therefore, by forming the diaphragm from the alloy composition having a low Young's modulus described above, the difference between the maximum volume and the minimum volume is increased, and the fluid transfer speed of the pump can be increased. Further, since the yield strength of the plastic alloy used for the diaphragm is large, plastic deformation is less likely to occur in the diaphragm due to the force applied to the diaphragm by the driving means.

Next, another example of the diaphragm pump will be described. FIG. 4 is a diagram showing a configuration of another example of the diaphragm pump of the present invention. The principle of transferring the fluid of the diaphragm pump having the configuration shown in FIG. 4 is the same as that of the pump shown in FIG. In the diaphragm pump shown in FIG. 4, a pump chamber 15 is formed by providing a diaphragm 4 made of the above-described alloy composition around a driving means 16. With such a configuration, the difference between the maximum volume and the minimum volume of the pump chamber 15 can be further increased, and the transfer speed of the pump can be further increased.

Gas is sucked into the pump chamber 15 through the intake valve 12, and when the internal volume of the pump chamber decreases, the discharge valve 13
The diaphragm pump can also be used as a gas compressor by utilizing the compressed gas exhausted through the gas pump. By forming the diaphragm from the above-described alloy composition, the difference between the maximum volume and the minimum volume of the pump chamber increases, and the gas compressibility can be increased.

The application of the diaphragm of the present invention is not limited to a diaphragm valve, a diaphragm pump or the like. For example, a diaphragm pressure gauge can be mentioned as an application example of the diaphragm of the present invention. The diaphragm pressure gauge has a structure in which the inside of a container is partitioned into two rooms by a diaphragm, and measures the amount of elastic deformation of the diaphragm due to a pressure difference when a fluid having a different pressure is introduced into one room and the other room. By detecting, the pressure of the fluid is measured. The amount of elastic deformation of the diaphragm may be directly detected by the amount of deformation, or a method is known in which the diaphragm is used as a movable electrode and is detected from a change in capacitance between the diaphragm and a separately provided fixed electrode. The flexibility of the diaphragm directly affects the sensitivity of the pressure gauge. Since the diaphragm of the present invention has a very small Young's modulus, the deformation is large even with the same pressure difference.
Therefore, a highly sensitive pressure gauge can be provided by using the diaphragm of the present invention.

[0035]

As described above, by using a diaphragm formed of an alloy composition having a Young's modulus of 90 GPa or less and a yield strength of 100 MPa or more, a diaphragm valve with a wide flow rate control range and a diaphragm with a high fluid transfer speed are used. A pump, a diaphragm compressor having a high compression ratio, a diaphragm vacuum gauge with high sensitivity, and the like can be provided.

[0036]

EXAMPLES Each composition described in Table 2 was charged into an arc furnace, and each composition was melted and mixed by arc heating, and then poured into a mold, and an ingot of each alloy composition (sample numbers 1 to 9) was prepared. Produced. A sample was cut out from the produced ingot and analyzed by an X-ray diffraction method. As a result, it was confirmed that all the produced alloy compositions were a single-phase solid solution and had a body-centered cubic structure.

For each of the prepared alloy compositions,
Young's modulus E, yield strength σy, ultimate tensile strength (rupture strength) σu, elastic elongation limit εe, elongation at break εf, and Vickers strength Hv were measured, and the measurement results are shown in Table 2. The ratio of the Young's modulus of the alloy composition (E) to the Young's modulus of the stainless steel (E _sus ) (E / E _sus ), the ratio of the yield strength to the Young's modulus of the alloy composition (σy / E), and the alloy composition Ratio of Vickers hardness to Young's modulus (Hv
/ E) is shown in Table 2. σy / E and Hv / E are effective for judging the quality of mechanical properties in practical use of the alloy composition, and the larger these values, the more preferable. The value of σy / E is preferably 0.010 or more, and more preferably 0.015 or more. The value of Hv / E is preferably 0.005 or more.

[0038]

[Table 2]

Even if the material has a small Young's modulus, if the yield strength or the Vickers hardness is small, it is not preferable for practical use in a diaphragm. For example, when a material having both a small Young's modulus and a low yield strength is used for the diaphragm of the diaphragm valve, plastic deformation is likely to occur in the diaphragm due to the force applied during valve operation. If the composition of the diaphragm is deformed, it may be impossible to control the flow rate accurately or the fluid may leak while the valve is closed.

The Young's modulus of the prepared alloy composition is less than 1/3 of that of stainless steel (refer to the value of E / _Esus in Table 2), so that the elastic deformation is large and the flow control range of the diaphragm valve is large. It can be seen that this is a preferable material for widening. Further, the yield strength of the produced alloy composition is three times or more that of stainless steel, and it can be seen that the alloy composition is hardly plastically deformed by the force applied to the diaphragm.

Next, each of the obtained ingots was rolled to produce a 0.5 mm-thick diaphragm. A diaphragm valve having the structure shown in FIG. 1 was manufactured by using two obtained diaphragms for each alloy composition. And, for comparison, using a stainless steel diaphragm,
A diaphragm valve having the configuration shown in FIG. 1 was manufactured. In each of the diaphragm valves, the distance between the diaphragm and the valve seat was set to a maximum as long as the diaphragm was not plastically deformed when the valve was closed.

A pipe was connected to the diaphragm valve manufactured as described above, water was allowed to flow, and the flow rate of the water was observed. In each of the diaphragm valves of the present invention and the diaphragm valve using stainless steel, water did not leak when the valves were closed.
When the valve was fully opened, it was confirmed that the flow rate of the water flowing out of the diaphragm valve of the present invention was larger and the control range of the flow rate was wider.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing a configuration of an example of a diaphragm valve of the present invention.

FIG. 2 is a cross-sectional view schematically showing the configuration of another example of the diaphragm valve of the present invention.

FIG. 3 is a diagram schematically showing a configuration of an example of the diaphragm pump of the present invention.

FIG. 4 is a diagram schematically showing the configuration of another example of the diaphragm pump of the present invention.

[Explanation of symbols]

 1, 2 flow path 3 fluid chamber 4 diaphragm 5 valve stem 6 handle 7 valve seat 8 electromagnetic motor 9 piezoelectric actuator 10 piezoelectric vibrator 11 ball screw 12 suction valve 13 discharge valve 14 container 15 pump chamber 16 drive means 17 diaphragm is elastically deformed Direction 18 electric motor 19 crankshaft

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Akihisa Inoue 35-35 Kawauchi Moto-Hasekura, Aoba-ku, Sendai-shi, Miyagi 11-806 Fuchi term (reference) 3H062 AA02 CC05 3H077 AA00 CC02 DD02 DD12 FF08 FF12 FF22 3J045 AA04 AA06 BA04 EA10

Claims (12)

[Claims] 1. A diaphragm comprising an alloy composition having a Young's modulus of 90 GPa or less and a yield strength of 100 MPa or more. 2. The diaphragm according to claim 1, wherein the alloy composition has a composition represented by the following formula. ## STR1 ## _{Ti 100-abcd M a M '} b M "c V d [ where, M represents, Zr, and one or both of Hf, M' is, Nb, in one or both of Ta M ″ is one or two or more elements selected from the group consisting of Cr, Mo, W, and Sn, and a, b, c,
And d is 5 ≦ a ≦ 40, 1 ≦ b ≦ 30, 0
≦ c ≦ 10, 0 ≦ d ≦ 20, 10 ≦ a + b + c + d ≦ 6
It is a numerical value that satisfies 0. ] 3. The diaphragm according to claim 2, wherein the alloy composition has a composition represented by the following formula. ## STR2 ## _{Ti 100-abcd Zr a M '} b M "c V d [ where, M' is, Nb, and one or both of Ta, M" is, Cr, Mo, W, and the Sn One or more elements selected from the group consisting of a, b,
c and d are respectively 5 ≦ a ≦ 40, 1 ≦ b ≦ 3
0, 0 ≦ c ≦ 10, 0 ≦ d ≦ 20, 10 ≦ a + b + c +
It is a numerical value satisfying d ≦ 60. ] 4. A diaphragm valve having a diaphragm made of an alloy composition having a Young's modulus of 90 GPa or less and a yield strength of 100 MPa or more. 5. The diaphragm valve according to claim 4, wherein the alloy composition has a composition represented by the following formula. ## STR3 ## _{Ti 100-abcd M a M '} b M "c V d [ where, M represents, Zr, and one or both of Hf, M' is, Nb, in one or both of Ta M ″ is one or two or more elements selected from the group consisting of Cr, Mo, W, and Sn, and a, b, c,
And d is 5 ≦ a ≦ 40, 1 ≦ b ≦ 30, 0
≦ c ≦ 10, 0 ≦ d ≦ 20, 10 ≦ a + b + c + d ≦ 6
It is a numerical value that satisfies 0. ] 6. The diaphragm valve according to claim 5, wherein the alloy composition has a composition represented by the following formula. Embedded image _{Ti 100-abcd Zr a M '} b M "c V d [ where, M' is, Nb, and one or both of Ta, M" is, Cr, Mo, W, and the Sn One or more elements selected from the group consisting of a, b,
c and d are respectively 5 ≦ a ≦ 40, 1 ≦ b ≦ 3
0, 0 ≦ c ≦ 10, 0 ≦ d ≦ 20, 10 ≦ a + b + c +
It is a numerical value satisfying d ≦ 60. ] 7. The diaphragm valve according to claim 4, wherein an electromagnetic motor is provided on one surface of the diaphragm via a piezoelectric actuator. 8. The diaphragm valve according to claim 7, wherein the piezoelectric actuator is formed by laminating two or more piezoelectric elements. 9. The diaphragm valve according to claim 7, wherein the electromagnetic motor is a stepping motor. 10. A diaphragm pump having a diaphragm made of an alloy composition having a Young's modulus of 90 GPa or less and a yield strength of 100 MPa or more. 11. The diaphragm pump according to claim 10, wherein the alloy composition has a composition represented by the following formula. Embedded image _{Ti 100-abcd M a M '} b M "c V d [ where, M represents, Zr, and one or both of Hf, M' is, Nb, in one or both of Ta M ″ is one or two or more elements selected from the group consisting of Cr, Mo, W, and Sn, and a, b, c,
And d is 5 ≦ a ≦ 40, 1 ≦ b ≦ 30, 0
≦ c ≦ 10, 0 ≦ d ≦ 20, 10 ≦ a + b + c + d ≦ 6
It is a numerical value that satisfies 0. ] 12. The diaphragm pump according to claim 11, wherein the alloy composition has a composition represented by the following formula. Embedded image _{Ti 100-abcd Zr a M '} b M "c V d [ where, M' is, Nb, and one or both of Ta, M" is, Cr, Mo, W, and the Sn One or more elements selected from the group consisting of a, b,
c and d are respectively 5 ≦ a ≦ 40, 1 ≦ b ≦ 3
0, 0 ≦ c ≦ 10, 0 ≦ d ≦ 20, 10 ≦ a + b + c +
It is a numerical value satisfying d ≦ 60. ]