CN111537174B

CN111537174B - Variable-angle ultrasonic impact test device and method

Info

Publication number: CN111537174B
Application number: CN202010353665.6A
Authority: CN
Inventors: 张彦虎; 段雪飞; 符昊; 纪敬虎
Original assignee: Jiangsu University
Current assignee: Jiangsu University
Priority date: 2020-04-29
Filing date: 2020-04-29
Publication date: 2021-11-23
Anticipated expiration: 2040-04-29
Also published as: CN111537174A

Abstract

The invention provides a variable-angle ultrasonic impact test device and method, which comprises a supporting table, a prepressing plate, a Lanjiwen vibrator and an impact carrying table, wherein a threaded hole is formed in the middle of each surface of the upper end of the supporting table, the prepressing plate is incompletely fixed through a bolt and used for supporting the Lanjiwen vibrator, the Lanjiwen vibrator is used for adjusting a plurality of impact attack angles in the range of 0-180 degrees on the supporting table, and different friction materials are respectively or simultaneously pasted on an impact area at the lower end of an amplitude transformer and the upper surface of the impact carrying table, so that ultrasonic impact fatigue or abrasion tests of different types of friction materials are realized.

Description

Variable-angle ultrasonic impact test device and method

Technical Field

The invention belongs to the field of ultrasonic vibration application, and particularly relates to a variable-angle ultrasonic impact test device and method.

Background

In recent years, ultrasonic impact plays a very important role in scientific research and engineering application aspects such as material modification (such as reduction of metal surface roughness and elimination of welding residual stress), ultrasonic catalysis, ultrasonic measurement, ultrasonic driving and the like. However, the problems of fatigue and abrasion of the contact surface of the impact head and the impacted member under ultrasonic impact are needed to be studied deeply, and related test methods and devices are more rare. Chinese patent (CN108715926A) discloses an ultrasonic impact device, in which the vibrator is fixed and the ultrasonic impact with variable angle cannot be realized. Researches show that the ultrasonic impacts at different angles have different impact action degrees on the contact surface, so that the ultrasonic impact test at a variable angle is realized, and the exploration of the fatigue and abrasion problems of the contact surface and the performance evaluation of special functional materials are particularly important.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a variable-angle ultrasonic impact test device and method, which are used for realizing fatigue or abrasion tests of the contact surface of an impact area of a vibrator and an impact carrying platform under various impact attack angles.

The present invention achieves the above-described object by the following technical means.

A variable angle ultrasonic impact test device comprises a supporting table, a prepressing plate, a Langewen vibrator and an impact carrying table; the supporting table is of a hollow polyhedral structure, an arc-shaped through hole is formed in the center of the bottom of the supporting table, an impact loading platform is placed in the center of the bottom surface of the arc-shaped through hole, a threaded hole is formed in the middle of each surface of the upper end of the supporting table, a prepressing plate is incompletely fixed through a bolt and used for supporting the Lanjiwen vibrator, and the bottom end of the Lanjiwen vibrator is in contact with the impact loading platform; the bolt is also sleeved with a spring.

In the technical scheme, the Lanjie oscillator comprises a threaded connecting rod, a nut, a rear end cover, n +1 electrode plates, n piezoelectric ceramics and an amplitude transformer which are sequentially arranged from top to bottom, wherein a threaded area at the upper end of the threaded connecting rod penetrates through the rear end cover to be matched with the nut, a threaded area at the lower end of the threaded connecting rod is matched with the amplitude transformer, and a polished rod area sequentially penetrates through the electrode plates and the piezoelectric ceramics which are alternately combined.

In the technical scheme, after the electrode plates and the piezoelectric ceramics are alternately combined, the electrode plates and the piezoelectric ceramics are equally divided into two parts which are the same up and down through the pre-pressing plate.

In the technical scheme, the electrode plate is connected with an external power supply.

In the technical scheme, the length of the polished rod area is the sum of the thicknesses of the electrode plate, the piezoelectric ceramic and the pre-pressing plate.

In the above technical scheme, the rear end cover is a hollow cylinder, and the radius of the central hole of the upper end surface is smaller than that of the central hole of the lower end surface.

In the technical scheme, the upper end of the amplitude transformer is of a quadrangular frustum pyramid structure, a cylinder which is in contact with the electrode plate at the lowest layer is arranged on the quadrangular frustum pyramid, and an impact area at the lower end of the amplitude transformer is of a semicircular structure and is in contact with the impact carrying platform.

A variable-angle ultrasonic impact test method is characterized in that different friction materials are respectively or simultaneously adhered to an impact area at the lower end of an amplitude transformer and the upper surface of an impact platform deck, a prepressing plate is incompletely fixed on the upper end surface of a support platform through a bolt in sequence, the prepressing plate is pressed down by screwing the bolt, a Langerhan vibrator applies prepressing force to the impact platform deck, the Langerhan vibrator is electrified and vibrated, and ultrasonic impact contact surface fatigue or abrasion tests of different types of friction materials at different angles are carried out.

Furthermore, the same friction material can be simultaneously stuck to the impact area at the lower end of the amplitude transformer and the upper surface of the impact carrying platform.

The invention has the beneficial effects that: the invention realizes the angle-variable ultrasonic impact test by utilizing the inverse piezoelectric effect of the piezoelectric ceramic according to different positions of the Langewen vibrator on the support platform. Different friction materials are pasted on the bottom end impact area of the Lanjie oscillator, different friction materials are pasted on the upper surface of the impact carrying platform, the same or different friction materials are pasted on the bottom end impact area of the Lanjie oscillator and the upper surface of the impact carrying platform at the same time, and the ultrasonic impact fatigue or abrasion tests of different types of friction materials are realized. The device has simple structure and provides technical support for researching the fatigue or abrasion of the ultrasonic impact contact surface.

Drawings

FIG. 1 is an assembly schematic view of the variable angle ultrasonic impact testing apparatus of the present invention;

FIG. 2 is a side cross-sectional view of a variable angle ultrasonic impact testing apparatus according to the present invention;

FIG. 3 is a schematic view of a threaded connecting rod of the present invention;

FIG. 4 is a cross-sectional view of the rear end cap of the present invention;

FIG. 5 is a schematic view of a support table according to the present invention;

FIG. 6 is a schematic illustration of a pre-press plate of the present invention;

FIG. 7 is a schematic view of a horn of the present invention;

in the figure: 1-threaded connecting rod, 2-nut, 3-rear end cover, 4-electrode plate, 5-piezoelectric ceramic, 6-amplitude transformer, 7-spring, 8-prepressing plate or flange, 9-bolt, 10-support table, 11-Lanjie oscillator and 12-impact carrier.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. Example embodiments may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. The drawings are only for purposes of illustrating the embodiments and are not to scale.

As shown in fig. 1 and 2, the variable-angle ultrasonic impact test device comprises a langevin vibrator 11, an impact stage 12, a spring 7, a pre-pressing plate 8, a bolt 9 and a support table 10, wherein the pre-pressing plate 8 can also adopt a flange.

As shown in fig. 5, the support platform 10 is a hollow polyhedron structure, and a circular arc-shaped through hole is formed in the center of the bottom, so that the support rigidity of the support platform 10 is improved by utilizing the arch principle, the vibration of the support platform 10 is reduced, and the connection flexibility of the amplitude transformer 6 is ensured. The impact carrier 12 is placed at the center of the bottom surface of the circular arc-shaped through hole, and the impact carrier 12 can be replaced and the ultrasonic impact test can be observed through the circular arc-shaped through hole; threaded holes are formed in the middle of each surface of the upper end, the distances from all the threaded holes to the center of the impact carrier 12 are equal, multiple impact attack angles can be adjusted within the range of 0-180 degrees, and the prepressing plate 8 is not completely fixed through the threaded holes through bolts 9, so that the prepressing plate 8 only keeps the moving freedom degree in the vertical direction; as shown in fig. 6, the pre-pressing plate 8 is provided with three through holes, the through holes on both sides are used for inserting the bolts 9, and the middle through hole is used for inserting the lower end of the threaded connecting rod 1 of the langevin vibrator 11. The position of a polished rod area of the bolt 9 is sleeved with a spring 7.

The Langevin vibrator 11 comprises a threaded connecting rod 1, a nut 2, a rear end cover 3, n +1 electrode plates 4, n piezoelectric ceramics 5 and an amplitude transformer 6 which are arranged in sequence from top to bottom, wherein the electrode plates 4 are connected with an external power supply; the electrode plates 4 and the piezoelectric ceramics 5 are alternately combined and are divided into two parts which are the same up and down through the prepressing plate 8. As shown in fig. 3, the middle part of the threaded connecting rod 1 is a polished rod area, the upper end and the lower end are threaded areas, the lower threaded area passes through a middle through hole of the prepressing plate 8 to be matched with a central threaded hole of the amplitude transformer 6, the upper threaded area passes through the rear end cover 3 to be matched with the nut 2, the polished rod area sequentially passes through the electrode plate 4 and the piezoelectric ceramic 5, and the length of the polished rod area is the sum of the thicknesses of the electrode plate 4, the piezoelectric ceramic 5 and the prepressing plate 8; as shown in fig. 4, the rear end cap 3 is a hollow cylinder, the radius of the central hole of the upper end surface is different from that of the central hole of the lower end surface, the radius of the central hole of the upper end surface is smaller than that of the central hole of the lower end surface, and the two end surfaces of the rear end cap 3 have higher flatness, so that the preset pressing force applied by screwing the nut 2 is ensured to be uniformly distributed on the electrode plate 4 contacting with the rear end cap 3; the amplitude transformer 6 is positioned at the lowest end of the Lanjivin oscillator 11, as shown in FIG. 7, the upper end of the amplitude transformer 6 is of a quadrangular frustum pyramid structure, a cylinder with the height of 2mm is arranged on the quadrangular frustum pyramid, the cylinder is in contact with the electrode slice 4 at the lowest layer, and a threaded hole is formed in the center of the quadrangular frustum pyramid and is matched with the lower end of the threaded connecting rod 1; the impact area of the lower end of the horn 6 is designed to be a semicircular structure (fig. 2) and is in contact with the impact carrier 12.

Different friction materials are adhered to the impact area at the lower end of the amplitude transformer 6, the threaded hole in the upper end face of the support table 10 is used for incompletely fixing the prepressing plate 8 through the bolt 9 in sequence, the screwing bolt 9 presses the prepressing plate 8 downwards through the spring 7, the Langerhan vibrator 11 exerts prepressing force on the impact carrying table 12, the electrode plate 4 is connected with an external power supply, the Langerhan vibrator 11 is electrified and vibrated, and ultrasonic impact contact surface fatigue or abrasion tests of different types of friction materials at different angles are carried out.

Different friction materials are adhered to the upper surface of the impact carrying platform 12, threaded holes in the upper end face of the supporting platform 10 are sequentially and incompletely fixed with the prepressing plate 8 through the bolts 9, the prepressing plate 8 is pressed down through the screwing bolts 9 through the springs 7, the Langerhan vibrator 11 exerts prepressing force on the impact carrying platform 12, the electrode plate 4 is connected with an external power supply, the Langerhan vibrator 11 is electrified and vibrated, and ultrasonic impact contact surface fatigue or abrasion tests of different types of friction materials at different angles are carried out.

The same or different friction materials are simultaneously adhered to the impact area at the lower end of the amplitude transformer 6 and the upper surface of the impact carrier 12, the threaded hole in the upper end surface of the support table 10 is sequentially provided with the bolt 9 to incompletely fix the prepressing plate 8, the screwing bolt 9 presses the prepressing plate 8 downwards through the spring 7, the Langerwen vibrator 11 applies prepressing force to the impact carrier 12, the electrode plate 4 is connected with an external power supply, the Langerwen vibrator 11 is electrified and vibrated, and ultrasonic impact contact surface fatigue or abrasion tests of different types of friction materials at different angles are carried out.

The friction material can be silicon carbide ceramic, polytetrafluoroethylene, KN99898 wear-resistant granular glue, polyurethane and the like.

The above embodiments are only used for illustrating the design idea and features of the present invention, and the purpose of the present invention is to enable those skilled in the art to understand the content of the present invention and implement the present invention accordingly, and the protection scope of the present invention is not limited to the above embodiments. Therefore, all equivalent changes and modifications made in accordance with the principles and concepts disclosed herein are intended to be included within the scope of the present invention.

Claims

1. A variable-angle ultrasonic impact test device is characterized by comprising a supporting table (10), a prepressing plate (8), a Lanjiwen vibrator (11) and an impact carrying table (12); the supporting table (10) is of a hollow polyhedral structure, the center of the bottom of the supporting table is provided with an arc-shaped through hole, an impact carrying table (12) is placed at the center of the bottom surface of the arc-shaped through hole, a threaded hole is formed in the middle of each surface of the upper end of the supporting table (10), a prepressing plate (8) is incompletely fixed through a bolt (9) through the threaded hole, the prepressing plate (8) is used for supporting a Lanjiwen vibrator (11), and the bottom end of the Lanjiwen vibrator (11) is in contact with the impact carrying table (12); the bolt (9) is also sleeved with a spring (7).

2. The angle-variable ultrasonic impact test device according to claim 1, wherein the lange wen vibrator (11) comprises a threaded connecting rod (1), a nut (2), a rear end cover (3), n +1 electrode plates (4), n piezoelectric ceramics (5) and a variable amplitude rod (6) which are sequentially arranged from top to bottom, an upper end threaded area of the threaded connecting rod (1) penetrates through the rear end cover (3) to be matched with the nut (2), a lower end threaded area of the threaded connecting rod is matched with the variable amplitude rod (6), and a polished rod area sequentially penetrates through the electrode plates (4) and the piezoelectric ceramics (5) which are alternately combined.

3. The ultrasonic impact test device with the variable angle according to claim 2, wherein the electrode sheet (4) and the piezoelectric ceramic (5) are alternately combined and then are divided into two parts which are the same up and down through the pre-pressing plate (8).

4. The variable-angle ultrasonic impact test device according to claim 3, wherein the electrode sheet (4) is connected with an external power supply.

5. The variable-angle ultrasonic impact test device according to claim 2, wherein the polish rod region length is the sum of the thicknesses of the electrode plate (4), the piezoelectric ceramic (5) and the pre-pressing plate (8).

6. The variable angle ultrasonic impact test device according to claim 2, wherein the rear end cap (3) is a hollow cylinder, and the radius of the central hole of the upper end face is smaller than that of the central hole of the lower end face.

7. The variable-angle ultrasonic impact test device according to claim 2, wherein the upper end of the amplitude transformer (6) is of a quadrangular frustum pyramid structure, a cylinder which is in contact with the lowermost electrode plate (4) is arranged on the quadrangular frustum pyramid, and an impact area at the lower end of the amplitude transformer (6) is of a semicircular structure and is in contact with the impact carrier (12).

8. A variable angle ultrasonic impact test method of a variable angle ultrasonic impact test device according to any one of claims 1-7, characterized in that different friction materials are respectively or simultaneously adhered to the impact area at the lower end of an amplitude transformer (6) and the upper surface of an impact carrier (12), the prepressing plate (8) is incompletely fixed on the upper end surface of a support table (10) sequentially through a bolt (9), the prepressing plate (8) is pressed down by screwing the bolt (9), a Langerhan vibrator (11) applies prepressing force to the impact carrier (12), the Langerhan vibrator (11) is electrified and vibrated, and ultrasonic impact contact surface fatigue or abrasion tests of different types of friction materials at different angles are carried out.

9. The ultrasonic impact test method with the variable angle according to claim 8, characterized in that the impact area at the lower end of the horn (6) and the upper surface of the impact carrier (12) can be simultaneously adhered with the same friction material.