CN110530750B

CN110530750B - Wear tester under high temperature environment

Info

Publication number: CN110530750B
Application number: CN201910746437.2A
Authority: CN
Inventors: 杨洪伟; 陈倩; 赵迎春; 龙胜刚; 高阳
Original assignee: AECC Guiyang Engine Design Research Institute
Current assignee: AECC Guiyang Engine Design Research Institute
Priority date: 2019-08-13
Filing date: 2019-08-13
Publication date: 2022-10-21
Anticipated expiration: 2039-08-13
Also published as: CN110530750A

Abstract

The invention discloses a wear tester in a high-temperature environment, which comprises an electric furnace and a vibration test device, wherein the electric furnace is of a half-split structure and is combined and surrounded outside the vibration test device, and the vibration test device comprises a vibration table, a bracket and a test piece clamp; the tester can simulate the high-temperature working environment of the turbine blade of the engine more truly; the method can simulate the relationship among the material, the surface roughness and the pressing force and the abrasion loss of the insert under four working conditions of collision, compression abrasion, linear contact abrasion and rotary scraping and grinding of the turbine blade shroud wear-resistant insert, find the factor influencing the maximum friction and abrasion, provide test data support for designing and improving an aircraft engine turbine blade shroud mechanism, simulate four different vibration states of an engine turbine blade and corresponding abrasion modes, and have the highest test temperature of 1000 ℃.

Description

Wear tester under high temperature environment

Technical Field

The invention belongs to the technical field of aero-engines, and particularly relates to a wear tester in a high-temperature environment.

Background

The blade shroud of the turbine blade of the aero-engine is provided with the wear-resistant insert, so that the vibration reduction effect is achieved. When the turbine blade is installed for the first time, the adjacent wear-resistant inserts are in a compression state. However, as the amount of wear increases, the pressing force between adjacent inserts decreases, so that the damping effect gradually decreases, and the damping capability is lost. The turbine blades which lose the vibration damping effect will break at the position with larger vibration stress, and great threat is caused to the safety of the airplane. Because the turbine blade works in high-temperature gas above 1000 ℃, no effective test method is available for approximation simulation at present.

Disclosure of Invention

The purpose of the invention is as follows: in order to solve the problems, the invention designs a wear tester in a high-temperature environment, and the tester can be used as a fretting wear test device for simulating the damping insert of the turbine shroud of the engine in the high-temperature environment.

The technical scheme is as follows: the abrasion tester in the high-temperature environment comprises an electric furnace and a vibration test device, wherein the electric furnace is of a half-split structure, the vibration test device is surrounded by a combination, and the vibration test device comprises a vibration table, a support and a test piece clamp.

Furthermore, the support is arranged on the vibrating table and comprises a left support, a right support, an upper mounting base plate, an insert support and a first insert, the upper mounting base plate is fixedly arranged on the left support and the right support, the insert support is fixedly arranged on the upper mounting base plate, and the first insert is connected with the insert support. The left support and the right support are installed on the vibrating table through bolts, and the left support and the right support, the upper installation base plate and the insert support are installed in a connected mode through bolts. In addition, the first insert is fixedly connected with the insert bracket through brazing.

Furthermore, the test piece fixture is installed on the vibration end of the vibration table and comprises a fixture base, a test piece installation frame, a test piece compression block, a test piece and a second insert, wherein the fixture base is installed on the vibration end of the vibration table, the test piece installation frame is arranged on the upper portion of the fixture base, the test piece compression block fixes the test piece through bolts and is arranged on the test piece installation frame, and the test piece is connected with the second insert.

Furthermore, the fixture base comprises a front blocking plate, a rear blocking plate and a dovetail groove, the test piece mounting rack further comprises an adjusting nut and a locking nut, the dovetail groove is fixed by the front blocking plate and the rear blocking plate, and the test piece mounting rack is mounted on the dovetail groove and moves and is fixed in the dovetail groove through the adjusting nut and the locking nut.

Further, the friction surfaces of the first insert and the second insert are in contact. When the length of the test piece 12 is 90-100mm, the width is 13-15mm, and the thickness is 2-4mm, the two inserts of the invention are contacted most sufficiently, and the effect is best.

Furthermore, a vertical observation window is arranged above the electric furnace corresponding to the first insert and the second insert, and the observation window is made of quartz glass.

The beneficial technical effects are as follows: the invention can simulate the high-temperature working environment of the turbine blade of the engine more truly; the method can simulate the relationship among the material, the surface roughness and the pressing force and the abrasion loss of the insert under four working conditions of the turbine shroud wear-resistant insert collision, the pressing wear, the linear contact wear and the rotary scraping and grinding, find the factor influencing the maximum friction and wear, and provide test data support for designing and improving the turbine shroud mechanism of the aircraft engine. Compared with the prior art, the invention has the following remarkable advantages:

(1) The cantilever beam vibration principle is adopted to simulate four different vibration states of the turbine blade of the engine and corresponding wear modes;

(2) An electric furnace is adopted for heating, and the high-temperature working environment of the turbine blade shroud of the engine is simulated. The test maximum temperature can reach 1000 ℃;

(3) The test piece is a simple cantilever beam with a rectangular cross section, so that finite element simulation calculation is facilitated. Tests, finite element simulations and mutual verification analysis of analytic solutions can be performed.

Drawings

FIG. 1 is a schematic external view of the present invention;

FIG. 2 is a schematic structural view of the present invention;

FIG. 3 is a schematic view of the vibration testing apparatus of the present invention;

FIG. 4 is an exploded view of the vibration testing apparatus of the present invention;

FIG. 5 is a schematic view of the test piece fixture of the present invention;

FIG. 6 is an exploded view of the trial holder of the present invention;

the test piece testing device comprises an electric furnace 1, a vibration testing device 2, a support 3, a test piece clamp 4, a vibrating table 5, a vertical observation window 6, a left support 7, a right support 7, an upper mounting base plate 8, a bolt 9M 8, an insert support 10, a first insert 11, a test piece 12, a locking nut 13, an adjusting nut 14, a front blocking plate 15, a rear blocking plate 15, a clamp base 16, a test piece pressing block 17, a test piece mounting frame 18, a clamp spring 19 and a second insert 20.

Detailed Description

This section is an embodiment of the present invention to help understand the purpose and concept of the present invention.

The tester of the invention comprises two parts, namely an electric furnace 1 and a vibration testing device 2. The electric furnace is a conventional resistance furnace, is designed in half, and can generate a high-temperature environment of 1000 ℃. The vibration test device 2 comprises a vibration table 5, a support 3 and a test piece clamp 4.

A vertical observation window 6 is designed above the electric furnace 1, and quartz glass (heat-insulating, transparent and visible internal material) is designed on the observation window.

The support 3 is installed on the vibrating table 5 through an M8 bolt 9, and the support 3 comprises a left support 7, a right support 7, an upper installation base plate 8, an insert support 10 and an insert 11. The left and right brackets 7 are connected with the vibrating table 5 through M8 bolts 9. The upper mounting base plate 8 is mounted on the left and right supports 7 by M8 bolts 9. The insert bracket 10 is mounted on the upper mounting base plate 8 through an M8 bolt 9. The first insert 11 is brazed on the insert support 10, and the vibration table can simulate the wear motion of the blade vibration through vibration.

The test piece clamp 4 is mounted on the vibration table 5 through an M8 bolt 9.

The test piece clamp 4 comprises a clamp base 16, a front blocking plate and a rear blocking plate 15, a test piece mounting frame 18, a test piece pressing block 17, an adjusting nut 14, a locking nut 13, a test piece 12 and a second insert 20. The front blocking plate 15, the rear blocking plate 15 and the clamp base 16 are connected 9 through M8 bolts, the clamp base 16 is provided with a dovetail groove, and a test piece mounting frame 18 which is also of a dovetail structure is mounted in the dovetail groove. The test piece mounting block 18 is slid in the dovetail groove by turning the adjusting nut 14. The adjusting nut 14 is positioned by a circlip 19. The test piece mounting bracket 18 is fixed in the dovetail groove by the M6 locking bolt 13. The test piece 12 is positioned and pressed through a test piece pressing block 17 and an M8 bolt (9), a second insert for testing is installed on a test piece mounting frame, the position of the mounting frame is adjusted to enable friction surfaces of the first insert and the second insert to be connected, and the second insert 20 is brazed at the top end of the test piece 12.

Another embodiment of the present invention is as follows.

The material of the test piece clamp 4 and the insert bracket 10 is GH2150, and the material of other parts is general stainless steel.

The test piece base body 12 was 95mm in length, 14mm in width and 3mm in thickness. The matrix material is K465 high-temperature alloy. One end of a base body of the test piece is provided with a wear-resistant insert, and the size of the insert is 6mm multiplied by 3mm multiplied by 2mm. The insert material is K4208. The insert is brazed on the test piece base body, the position of the insert is centered, the insert is flush with one end of the test piece base body, and the length direction of the insert is 6mm and the width direction of the test piece base body is 14 mm.

And assembling the test piece clamp. The jig is assembled according to the schematic view of the structure of the jig shown in fig. 5 and 6.

The extension length of the clamped test piece is 80mm.

The assembled test piece holder 4 is mounted on a vibration table 5. The mounting of the bracket 3 is according to fig. 3 and 4. Wherein the holder 3 comprises an insert holder 10 to which an insert of the same size as the test piece is also brazed, the insert being centrally located.

The relative positions of the test piece holder 4 and the support 3 are adjusted so that the friction surfaces (fig. 3) between the insert 11 on the test piece 12 and the insert 11 on the insert support 10 coincide.

Strain gauges are attached to two sides of the test piece base body 12 10mm away from the clamping position, the direction of each strain gauge is parallel to the length direction of the test piece base body, and the position of each strain gauge is centered.

A preload is generated between the friction surfaces by adjusting the nut 14. It was found from finite element calculations of the test pieces at room temperature that the positive pressures generated between the inserts 11 were 200N, 300N and 400N when the strain gauges measured the stresses of 652.7MPa, 787.4MPa and 877.8 MPa.

The furnace was installed and fixed as shown in fig. 1 and 2.

The test piece 12 has finite element calculations to determine the first bend resonant frequency of 259.2Hz and 1175.6Hz and the torsional resonant frequency of 2705.3Hz at 1000 ℃. The test piece clamp 4 and the vibration table 5 are rotated by 0.5 degrees relative to each other, and the input frequency is set to 1408.1Hz, so that the linear contact friction test can be simulated.

And a single laser measuring point is driven downwards through an observation window 6 designed on the electric furnace 1, and the vibration state of the insert position is detected. And taking the finite element resonance frequency calculation result as a reference, and searching the natural frequency of the test piece. Test points the table below shows.

Test point	Positive pressure (N)	Test temperature (. Degree. C.)	Input frequency (Hz)	Test conditions
					1	200	1000	259.2	Collision of vehicles
2	200	1000	1175.6	Pressing friction
					3	200	1000	2705.3	Rotary scraping mill
4	200	1000	1408.1	Friction by line contact
					5	300	1000	259.2	Impact of collision
6	300	1000	1175.6	Pressing friction
					7	300	1000	2705.3	Rotary scraping mill
8	300	1000	1408.1	Friction by line contact
					9	500	1000	259.2	Collision of vehicles
10	500	1000	1175.6	Pressing friction
					11	500	1000	2705.3	Rotary scraping mill
12	500	1000	1408.1	Friction by line contact

And recording the decay process of the positive pressure under the conditions of input frequency and temperature. The test was paused every 10 hours to observe and record the surface wear between the rubbing faces. The test was stopped when the positive pressure decayed to 60%.

The invention can also research the relationship between the factors influencing the performance of the friction surface, such as the surface roughness, the hardness, the material and the like of the wear-resistant insert and fretting wear.

Claims

1. The abrasion tester under the high-temperature environment is characterized by comprising an electric furnace (1) and a vibration test device (2), wherein the electric furnace (1) is of a half-split structure, the vibration test device (2) is surrounded in a combined mode, and the vibration test device (2) comprises a vibration table (5), a support (3) and a test piece clamp (4);

the support (3) is arranged on the vibrating table (5), the support (3) comprises a left support (7), a right support (7), an upper mounting base plate (8), an insert support (10) and a first insert (11), the upper mounting base plate (8) is fixedly arranged on the left support (7) and the right support (7), the insert support (10) is fixedly arranged on the upper mounting base plate (8), and the first insert (11) is connected with the insert support (10); the left support (7) and the right support (7) are mounted on the vibrating table (5) through bolts, and the left support (7), the right support, the upper mounting base plate (8) and the insert bracket (10) are mounted through bolts in a connecting mode; in addition, the first insert (11) is fixedly connected with the insert bracket (10) through brazing;

the test piece fixture (4) is arranged on the vibration end of the vibration table (5), the test piece fixture (4) comprises a fixture base (16), a test piece mounting frame (18), a test piece pressing block (17), a test piece (12) and a second insert (20), wherein the fixture base (16) is arranged on the vibration end of the vibration table (5), the test piece mounting frame (18) is arranged on the upper portion of the fixture base (16), the test piece pressing block (17) fixes the test piece (12) through a bolt and is arranged on the test piece mounting frame (18), and the test piece (12) is connected with the second insert (20);

the fixture base (16) comprises a front blocking plate and a rear blocking plate (15) and a dovetail groove, the test piece mounting rack (18) further comprises an adjusting nut (14) and a locking nut (13), the dovetail groove is fixed by the front blocking plate and the rear blocking plate (15), the test piece mounting rack (18) is installed on the dovetail groove and moves and is fixed in the dovetail groove through the adjusting nut (14) and the locking nut (13);

the friction surfaces of the first insert (11) and the second insert (20) are contacted.

2. A high temperature environment wear tester as claimed in claim 1, wherein the test piece (12) is 90 to 100mm long, 13 to 15mm wide and 2 to 4mm thick.

3. A wear tester in high temperature environment according to claim 1, characterized in that a vertical viewing window (6) is provided above the electric furnace (1) corresponding to the first insert (11) and the second insert (20).

4. A high temperature environment wear tester according to claim 1, characterized in that the vertical viewing window (6) is made of quartz glass.