An ultrasonic vibrator for drawing titanium and titanium alloy wires

Abstract

The present invention discloses an ultrasonic vibrator for drawing titanium and titanium alloy wires, which belongs to the technical field of ultrasonic vibrators and solves the problems of slow drawing speed and low drawing precision when drawing titanium and titanium alloy wires by hot drawing in the prior art. The present invention comprises a horn, a transducer and a wire drawing die arranged on the horn, wherein the transducer comprises a front end cover, a rear end cover, an even number of piezoelectric ceramics arranged between the front end cover and the rear end cover, and electrode sheets arranged between the piezoelectric ceramics and between the piezoelectric ceramics and the front end cover and the rear end cover respectively, and the front end cover is connected to the horn; a wire through hole is opened in the center of the horn, a wire drawing die is arranged on the horn at one end of the wire through hole, and a transducer is arranged on the other end. The present invention is used for drawing titanium and titanium alloy wires.

Description

Technical Field

[0001] The invention discloses an ultrasonic vibrator used for drawing titanium and titanium alloy wires, which belongs to the technical field of ultrasonic vibrators. Background Art

[0002] Since the yield strength ratio of titanium alloy is as high as 0.95 and the deformation resistance is large, titanium and titanium alloy wires with a diameter of 2mm to 10mm are generally produced by hot drawing without using traditional ultrasonic process. However, due to the poor thermal conductivity of titanium alloy and severe springback during hot drawing, the drawing speed of titanium alloy wire is lower than 0.5m / s, the wire breaks frequently and the efficiency is low during the drawing process, and the surface quality of the wire after drawing is poor and the dimensional accuracy is low. In order to obtain high-performance wire, titanium alloy wire needs to be calibrated and surface polished multiple times after hot drawing.

[0003] In order to solve the above technical problems, the existing technology uses an ultrasonic vibrator to draw the metal wire. Ultrasonic vibration drawing of the metal wire is a processing technology that superimposes ultrasonic vibration energy on the conventional wire drawing process. The alternating electrical signal generated by the ultrasonic driver is converted into ultrasonic vibration energy through a piezoelectric ceramic sheet, and the ultrasonic vibration energy is transmitted to the wire drawing die, thereby stimulating the vibration of the wire drawing die and the metal wire, and then obtaining the effect of ultrasonic vibration energy on the plastic forming of the metal material.

[0004] An ultrasonic vibrator is a device, also known as an ultrasonic vibrator. The whole after the transducer and the horn are connected is called a vibrator.

[0005] The transducer realizes the mutual conversion between electrical energy and mechanical energy (sound wave vibration) through the piezoelectric effect of piezoelectric ceramics, and amplifies the device through the front and rear radiation cover blocks with acoustic impedance matching.

[0006] Since the horn is a passive device, it does not generate vibration itself, but only changes the amplitude of the input vibration and then transmits it out, completing the impedance transformation.

[0007] Ultrasonic transducers can produce regular vibrations under electric field excitation, but the amplitude is generally around 10μm, which is not enough to directly complete welding and processing procedures.

[0008] Therefore, after the transducer is connected to a properly designed amplitude transformer, the amplitude of the ultrasonic wave can vary within a wide range. As long as the material strength is sufficient, the amplitude can exceed 100μm.

[0009] When the horn is in longitudinal extension and contraction vibration, the particle motion directions on the left and right sides of a certain cross section in the middle are just opposite, which is equivalent to the existence of a relatively static node surface. This node surface is called a node, which is also the best fixing point of the vibrator. Deviating from this node will reduce the working efficiency of the vibrator, commonly known as leakage wave.

[0010] Since the prior art of using ultrasound to draw metal wires is very rare, a related technology "CN106452162A-A patch-type fixed beam type orthogonal composite ultrasonic wire drawing vibrator" was retrieved. The ultrasonic wire drawing vibrator in this technology adopts a patch structure, but has the following shortcomings:

[0011] 1. The installation and manufacturing are complicated. Ceramic sheets are hard and brittle materials. They are very fragile when the thickness is small, and it is difficult to use them in industrial scenarios.

[0012] Second, the vibrator outputs small ultrasonic energy, weak strength and stiffness, and complex excitation;

[0013] 3. It cannot be used for processing wires with a diameter of more than 0.2 mm.

[0014] Moreover, the prior art of using ultrasonic vibrators to draw metal wires has many problems, and is particularly unsuitable for titanium and titanium alloy wires with a yield strength ratio of up to 0.95, large deformation resistance, and a diameter of 2 mm to 10 mm.

[0015] In summary, when hot drawing is used to draw titanium and titanium alloy wires in the prior art, there are problems such as slow drawing speed and low drawing accuracy; and the ultrasonic vibrator in the prior art is not suitable for drawing titanium and titanium alloys. Summary of the invention

[0016] The object of the present invention is to provide an ultrasonic vibrator for drawing titanium and titanium alloy wires, so as to solve the problems of slow drawing speed and low drawing precision when drawing titanium and titanium alloy wires by hot drawing in the prior art.

[0017] In order to achieve the above object, the technical solution adopted by the present invention is:

[0018] An ultrasonic vibrator for drawing titanium and titanium alloy wires, comprising a horn, a transducer arranged on the horn and a wire drawing die, wherein the transducer comprises a front end cover, a rear end cover, an even number of piezoelectric ceramics arranged between the front end cover and the rear end cover, and electrode sheets arranged between the piezoelectric ceramics and between the piezoelectric ceramics and the front end cover and the rear end cover, respectively, and the front end cover is connected to the horn;

[0019] A wire hole is provided at the center of the horn, a wire drawing die is arranged on the horn at one end of the wire hole, and a transducer is arranged on the other end.

[0020] Furthermore, at least two transducers are arranged on the horn.

[0021] Furthermore, the amplitude transformer is a conical rod, an exponential rod or a stepped rod.

[0022] Furthermore, a flange for fixing the ultrasonic vibrator is provided in the middle of the horn.

[0023] Furthermore, the front end cover, an even number of piezoelectric ceramics and the rear end cover are fixed by pre-tightening screws; the transducer and the amplitude transformer are connected by studs; and the wire drawing die is connected to the amplitude transformer thread.

[0024] Furthermore, the electrode sheet has a thickness of more than 0.3 mm and is made of a conductive material that is not prone to heat.

[0025] Further, the rear end cover material is a high-strength thermally conductive copper alloy;

[0026] The front end cover adopts a conical rod when the load changes greatly; a stepped rod should be adopted when the load is stable and the power requirement is high;

[0027] The number of the piezoelectric ceramics is determined according to the power, and they are excited by high-frequency AC voltage signals with equal amplitude and polarized along the thickness direction; the polarization polarities of two adjacent piezoelectric ceramics are opposite, and the piezoelectric ceramics work in the D33 mode.

[0028] Furthermore, the excitation frequency of the ultrasonic vibrator is equal to the maximum impedance frequency of the ultrasonic vibrator, the effective value of the driving voltage is not less than 1000V, and the ultrasonic vibrator works in a power bootstrap mode.

[0029] Compared with the prior art, the advantages of the present invention are:

[0030] 1. The ultrasonic vibrator in the present invention is a brand-new structure. The improved ultrasonic vibrator is used to ultrasonically draw titanium and titanium alloy wires, that is, the drawing die reciprocates along the axial direction of the titanium and titanium alloy wires at high frequency to achieve ultrasonic drawing; compared with the traditional processing technology, the drawing performance of titanium and titanium alloy wires has been greatly improved. The improvements include the following:

[0031] The amount of surface defects (cracks, pits, bumps and debris, etc.) can be reduced by 50%;

[0032] Ultrasonic waves are transmitted inside titanium and titanium alloy wires, forming acoustic stress inside titanium and titanium alloy wires, thereby reducing the deformation resistance of the wires, which can enable titanium and titanium alloys to be cold drawn and formed, reducing energy consumption by 60%;

[0033] The wire obtained by cold drawing has high dimensional accuracy, and only 1 to 2 size calibrations are needed to obtain high-precision and high-quality wire;

[0034] The wire breakage rate of titanium and titanium alloy wires is reduced, and the production yield rate can be increased by more than 15%.

[0035] The processing efficiency is improved, and the drawing speed is significantly increased, and can reach 1m / s;

[0036] Second, the electrode sheet in the present invention is 0.3 mm or more to prevent it from being too thin, which may affect the welding and fixing of the wire, that is, the electrode sheet is not rigid enough to effectively weld and fix the wire;

[0037] 3. The ultrasonic excitation mode of the ultrasonic vibrator of the present invention has changed. It adopts more than two half-wavelength transducers and an energy-focusing horn. The fixing method is simple. The power of the ultrasonic transducer is higher, which can reach 2000w. The strength and rigidity of the horn are higher, and the amplitude is larger.

[0038] Fourth, the present invention adopts a sandwich transducer, which has a stable structure, a long service life, a higher ultrasonic energy applied to the wire drawing process, and adopts a single longitudinal wave vibration, which is simple to excite; Fifth, the present invention can be used for the processing of titanium and titanium alloy wires with a diameter of more than 0.2 mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 is a cross-sectional view of the present invention;

[0041] Figure 2 is a three-dimensional schematic diagram of the present invention;

[0042] Figure 3 is a three-dimensional schematic diagram of a transducer in the present invention;

[0043] Figure 4 It is a schematic diagram of the polarization mode of the piezoelectric ceramic sheet in the present invention;

[0044] Figure 5 is a vibration mode diagram in the present invention;

[0045] Figure 6 It is an impedance curve diagram of the present invention.

[0046] In the figure: 1-transducer, 1-1-rear end cover, 1-2-pre-tightening screw, 1-3-piezoelectric ceramic, 1-4-front end cover, 2-amplifier, 2-1-flange, 2-2-through hole, 3-drawing die, 4-stud stud. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0049] In the description of the present invention, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the invention is usually placed when used. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0050] In addition, the terms “first”, “second”, “third”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0051] In addition, the terms "horizontal", "vertical", "overhanging", etc. do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0052] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", "connection", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0054] like Figure 1 , 2As shown in Figure 5, an ultrasonic vibrator for drawing titanium and titanium alloy wires includes a horn 2, a transducer 1 arranged on the horn 2, and a wire drawing die 3.

[0055] Among them, Figure 3 As shown, the transducer 1 includes a front end cover 1-4, a rear end cover 1-1, an even number of piezoelectric ceramics 1-3 arranged between the front end cover 1-4 and the rear end cover 1-1, and electrode sheets arranged between the piezoelectric ceramics 1-3 and between the piezoelectric ceramics 1-3 and the front end cover 1-4 and the rear end cover 1-1, and the front end cover 1-4 is connected to the horn 2;

[0056] The front end cover 1-4 is connected to the amplitude transformer 2 by a stud 4. Of course, it is not ruled out that other structures can be used for fixing; the front end cover 1-4, an even number of piezoelectric ceramics 1-3 and the rear end cover 1-1 are fixed by a pre-tightening screw 1-2. While the pre-tightening screw 1-2 fixes the front end cover 1-4, an even number of piezoelectric ceramics 1-3 and the rear end cover 1-1, the electrode sheets arranged between the piezoelectric ceramics 1-3 and between the piezoelectric ceramics 1-3 and the front end cover 1-4 and the rear end cover 1-1 are also fixed. Of course, it is not ruled out that other structures can be used for fixing.

[0057] The thickness of the electrode sheet is above 0.3mm, such as 0.4mm, 0.5mm, 0.6mm, etc., and the material is a conductive material that is not easy to generate heat, such as copper, etc.; the material of the rear end cover 1-1 is a high-strength thermal conductive copper alloy, such as beryllium copper C17200, etc.; the front end cover 1-4 adopts a conical rod when the load changes greatly; when the load is stable and the power requirement is high, a stepped rod should be used.

[0058] The number of piezoelectric ceramics 1-3 is determined according to the power and needs to be an even number. When there are odd numbers of piezoelectric ceramics in the polarization mode described in this case, it cannot work. For example, if there are 2, 4 or 6 piezoelectric ceramics, the more piezoelectric ceramics there are, the greater the output power and the greater the non-uniformity. Therefore, the best value is 4 piezoelectric ceramics, which are excited by high-frequency AC voltage signals with equal amplitude and polarized along the thickness direction. Figure 4 As shown, the polarization polarities of two adjacent piezoelectric ceramics are opposite, and the piezoelectric ceramics 1-3 work in the D33 mode. The piezoelectric ceramics 1-3 are excited by a high-frequency (greater than 20KHz) AC voltage signal with equal amplitude, and the inverse piezoelectric effect of the piezoelectric ceramics 1-3 polarized in the thickness direction generates high-frequency axial mechanical vibration, thereby realizing the ultrasonic vibration of the wire drawing die 3.

[0059] A through-wire hole 2-2 is provided at the center of the horn 2, a wire drawing die 3 is provided on the horn 2 at one end of the through-wire hole 2-2, and a transducer 1 is provided at the other end, and the wire drawing die 3 is threadedly connected to the horn 2. At least two transducers 1 are provided on the horn 2, and three or four transducers may be provided. The horn 2 is a conical rod, an exponential rod or a stepped rod, and of course, other structures may be provided.

[0060] The middle of the horn 2 is provided with a flange 2-1 for fixing the ultrasonic vibrator. The flange is provided and the purpose of the flange is to prevent the ultrasonic vibrator from not working due to the flange not being installed or / and the unreasonable selection of the installation point. Of course, it is not ruled out that other fixing structures can be used to replace the flange.

[0061] like Figure 6 As shown, the excitation frequency of the ultrasonic vibrator obtained above is equal to the maximum impedance frequency of the ultrasonic vibrator, the effective value of the driving voltage is not less than 1000V, and the ultrasonic vibrator works in the power bootstrap mode.

[0062] Example

[0063] During the drawing process of titanium and titanium alloy wires, the ultrasonic vibrator for drawing the titanium and titanium alloy wires is installed on the base through a clamp and a flange. After installation, the titanium and titanium alloy wires pass through the wire drawing die and the wire through hole. After passing through, the ultrasonic vibrator is started. The titanium and titanium alloy wires are processed by the ultrasonic vibrator and ultrasonic drawing to finally obtain high-quality drawn wires.

Claims

1. An ultrasonic vibrator for drawing titanium and titanium alloy wires, comprising a horn (2), a transducer (1) arranged on the horn (2) and a wire drawing die (3), characterized in that: The transducer (1) comprises a front end cover (1-4), a rear end cover (1-1), an even number of piezoelectric ceramics (1-3) arranged between the front end cover (1-4) and the rear end cover (1-1), and electrode sheets arranged between the piezoelectric ceramics (1-3) and between the piezoelectric ceramics (1-3) and the front end cover (1-4) and the rear end cover (1-1), respectively; the front end cover (1-4) is connected to a horn (2); A wire hole (2-2) is provided at the center of the horn (2); a wire drawing die (3) is arranged on the horn (2) at one end of the wire hole (2-2), and a transducer (1) is arranged on the other end; The front end cover (1-4) adopts a conical rod when the load changes greatly; and a stepped rod when the load is stable and the power requirement is high; A flange (2-1) for fixing the ultrasonic vibrator is provided in the middle of the horn (2); The front end cover (1-4), an even number of piezoelectric ceramics (1-3) and the rear end cover (1-1) are fixed by means of pre-tightening screws (1-2); the transducer (1) and the amplitude transformer (2) are connected by means of studs (4); and the wire drawing die (3) is threadedly connected to the amplitude transformer (2).

2. The ultrasonic vibrator for drawing titanium and titanium alloy wire according to claim 1, characterized in that: At least two transducers (1) are arranged on the horn (2).

3. The ultrasonic vibrator for drawing titanium and titanium alloy wire according to claim 2, characterized in that: The amplitude transformer (2) is a conical rod, an exponential rod or a stepped rod.

4. The ultrasonic vibrator for drawing titanium and titanium alloy wire according to claim 3, characterized in that: The electrode sheet has a thickness of more than 0.3 mm and is made of a conductive material that is not prone to heat.

5. The ultrasonic vibrator for drawing titanium and titanium alloy wire according to claim 4, characterized in that: The rear end cover (1-1) is made of a high-strength thermally conductive copper alloy; The number of the piezoelectric ceramics (1-3) is determined according to power, and they are excited by high-frequency alternating voltage signals with equal amplitudes and polarized along the thickness direction; the polarization polarities of two adjacent piezoelectric ceramics are opposite, and the piezoelectric ceramics (1-3) operate in a D33 mode.

6. The ultrasonic vibrator for drawing titanium and titanium alloy wires according to claim 5, characterized in that: The excitation frequency of the ultrasonic vibrator is equal to the maximum impedance frequency of the ultrasonic vibrator, the effective value of the driving voltage is not less than 1000V, and the ultrasonic vibrator works in a power bootstrap mode.

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