CN106092736A - A kind of metal plate-like sample Temperature High Cycle Fatigue test fixture - Google Patents

Abstract

The invention discloses a high-temperature and high-cycle fatigue test fixture for a metal plate sample, which is composed of a chuck, a chuck support rod, a fastening ring, a backup ring, and a base. The chuck has a chuck slot and a chuck support The mortise on the concave arc surface on the rod cooperates with the clamping, the fastening ring is installed on the upper end of the chuck strut, and the chuck strut is connected with the base and locked by the backup ring. There is an expansion wrench on the chuck strut, through the expansion wrench, put the test piece into the center of the chuck and center it, apply high-temperature lubricating oil on the screw hole of the fastening ring and the thread of the bolt and tighten it with a wrench. There is a penetrating water outlet in the base to connect with the water circulation cooling system, which can not only ensure a good cooling effect, but also save the cost of manufacturing the water cooling jacket. The fixture structure is simple, and the clamping method is easy to operate, which can ensure the axial fatigue test of the plate-shaped sample under the test conditions of the highest temperature environment of 1100 ℃, the highest axial load of 600MPa, and the frequency range of 90Hz-110Hz, and has good reliability. and clamping performance.

Description

A Fixture for High Temperature and High Cycle Fatigue Test of Metal Plate Specimen

technical field

The invention relates to a high-temperature high-cycle fatigue test clamping device for material testing, in particular to a high-temperature high-cycle fatigue test fixture for a metal plate sample.

Background technique

Existing published literature, "Research on High Cycle Fatigue Properties of DZ468 Alloy" ("Acta Metals", 2010, No. 6, pp. 708-714) and "High Cycle Fatigue Behavior of DD98M Nickel-based Single Crystal Superalloy at 900°C" (" Acta Metall Sinica, 2012, No. 2, pp. 170-175") introduced a test method for testing the high-temperature high-cycle fatigue performance of metals, that is, using rod-shaped specimens connected to the PLG-100 high-frequency fatigue testing machine. The test method described in the literature is the method used in the fatigue test of the traditional bar-shaped sample, and the fatigue test technology of the bar-shaped sample has been matured at present. However, the disadvantage of the rod-shaped sample is that it cannot simulate some special structural parts due to the shape limitation, and the rod-shaped sample will cause material waste for metal materials with a small original ingot size.

Invention patent 201410100602.4 proposes a fixture for fatigue testing of flat specimens. The main principle is to perform fatigue tests by clamping and fixing the specimen with wedge-shaped blocks. Although the fixture can be used for clamping plate specimens, the The clamping effect is limited. When the temperature rises to about 600°C, due to the stress relaxation caused by metal creep at high temperature, the clamp and the specimen will loosen when the load exceeds 200MPa and the high-frequency oscillation environment of 90Hz-110Hz causes clamping. Sustained failure, unable to meet the test requirements.

The important structural components of modern aero-engines and gas turbines often have to bear constant centrifugal force and high-frequency vibration force generated by hot gas injection in high-temperature service environments. High-temperature and high-cycle fatigue tests play an important role in simulating the effects of alternating loads and high-frequency vibration forces on metal properties of superalloy materials under complex stress states, and in studying the ultimate fatigue life of superalloy components. At present, the vibration frequency of the high cycle fatigue test equipment is 60Hz-180Hz, and the test usually uses a smooth round bar sample with threads, while the high frequency test for the plate sample is still in a blank state.

In order to realize the high-cycle fatigue test of the plate-shaped test piece under the condition of high temperature above 900°C, frequency of 90Hz-110Hz, and high load above 300MPa, a new type of fixture connection testing machine and test piece that is easy to operate, practical and reliable is needed.

Contents of the invention

In order to avoid the deficiencies in the prior art, the present invention proposes a fixture for high-temperature and high-cycle fatigue test of metal plate samples; Under the test conditions in the frequency range of 90Hz-110Hz, it has good reliability and clamping performance, effectively avoiding the data deviation caused by the performance of the fixture to the fatigue test.

The technical scheme that the present invention adopts to solve its technical problem is: comprise clip body, water-cooled base, clip body is installed on the water-cooled base, and water-cooled base is fixed on the testing machine; Described clip body includes chuck, chuck strut, fastening ring, fastening bolts, a plurality of chuck slots evenly distributed on the convex arc surface of one side of the chuck, the other side of the chuck is saw-toothed, the chuck strut is a cylindrical structure, and the chuck strut The upper end is processed with an inner concave arc surface, and the two inner concave arc surfaces are symmetrically distributed with multiple tenons. The tenons and the chuck slots are clamped together. There is an expansion wrench on the chuck support rod, and the expansion wrench is located on the chuck. Below the concave arc surface on the strut, the lower end of the chuck strut has an external thread of the chuck strut, the fastening ring is installed on the upper end of the chuck strut, and there are symmetrical screw holes in the center of both sides of the fastening ring. The fastening bolt and the screw hole are matched to tighten the upper end of the chuck strut;

The water-cooled base includes a tensioning ring and a base. The upper end of the base has base internal threads, the lower end of the base has base external threads, the base has a through water outlet, the lower end of the chuck strut is threadedly connected with the upper end of the base, and through The backup ring is locked, the lower end of the base is screwed to the testing machine, and the water outlet of the base is connected to the water circulation cooling system.

The number of chuck slots on the chuck is the same as the number of tenons on the chuck strut.

The chuck, fastening ring, and chuck strut are made of nickel-based superalloy.

Beneficial effect

The invention proposes a fixture for high-temperature and high-cycle fatigue test of a metal plate sample, which is composed of a chuck, a chuck brace, a fastening ring, a backup ring, and a base, and the chuck has a chuck slot and a chuck brace The mortise on the concave arc surface on the rod cooperates with the clamping, the fastening ring is installed on the upper end of the chuck strut, and the chuck strut is connected with the base and locked by the backup ring. There is an expansion wrench on the chuck strut, through the expansion wrench, put the test piece into the middle of the chuck and center it, apply high-temperature lubricating oil on the screw hole of the fastening ring and the thread of the bolt and tighten it with a wrench. There is a penetrating water outlet in the base to connect with the water circulation cooling system, which can not only ensure a good cooling effect, but also save the cost of manufacturing the water cooling jacket. The fixture structure is simple, and the clamping method is easy to operate, which can ensure the axial fatigue test of the plate sample under the test conditions of the highest temperature environment of 1100°C, the highest axial load of 600MPa, and the frequency range of 90Hz-110Hz, and has good reliability. and clamping performance.

Compared with existing technology:

One side of the chuck of the present invention is processed into a sawtooth shape to ensure the clamping and clamping effect. The collets are divided into different types according to the thickness, and different collets can be used according to the thickness of the test piece. The chuck maintains a certain thickness to prevent excessive bending and deformation of the chuck strut when clamping and tightening. The chuck strut is threadedly connected with the base and at the same time connected with the backup ring to ensure the high cycle fatigue test can be carried out.

The invention can meet the requirements of the axial fatigue test of the plate-shaped sample in the temperature range of 20°C-1100°C and the frequency of 90Hz-110Hz, and can maintain a good clamping ability in the test state, effectively avoiding the The deviation caused by the fixture performance problem to the fatigue test.

Description of drawings

A fixture for high-temperature and high-cycle fatigue testing of metal plate samples according to the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Fig. 1 is an axonometric view of a jig for a high-temperature high-cycle fatigue test of a metal plate sample according to the present invention.

Fig. 2 is a schematic diagram of the structure of the high-temperature high-cycle fatigue test fixture for the metal plate sample of the present invention.

Fig. 3 is a schematic diagram of the chuck of the jig of the present invention.

Fig. 4 is a schematic diagram of the chuck brace of the clamp of the present invention.

Fig. 5 is a left side view of the fastening ring of the clamp of the present invention.

Fig. 6 is a schematic diagram of the fastening ring of the clamp of the present invention.

Fig. 7 is a schematic diagram of fastening bolts of the clamp of the present invention.

Fig. 8 is a schematic diagram of the base of the clamp of the present invention.

Fig. 9 is a schematic diagram of the tensioning ring of the clamp of the present invention.

In the picture:

1. Chuck 2. Chuck slot 3. Tenon 4. Chuck strut 5. Expansion wrench 6. Chuck strut external thread 7. Fastening ring 8. Screw hole 9. Fastening bolt 10. Spare Tight ring 11. Base 12. Base internal thread 13. Water outlet 14. Base external thread

detailed description

This embodiment is a fixture for high temperature and high cycle fatigue testing of metal plate samples.

Referring to Figures 1 to 9, the fixture for high-temperature and high-cycle fatigue testing of metal plate samples in this embodiment consists of a clamp body and a water-cooled base. The clamp body is installed on the water-cooled base, and the water-cooled base is fixed on the testing machine. Among them, the clamp body includes chuck 1, chuck slot 2, tenon 3, chuck strut 4, expansion wrench 5, chuck strut external thread 6, fastening ring 7, screw hole 8, fastening bolt 9. Multiple chuck slots 2 are processed on the arc surface of one side of the chuck 1, and the other side of the chuck 1 is serrated. The chuck 1 is divided into several pairs according to different thicknesses, which are used for test pieces of different thicknesses. The upper end of the chuck strut 4 is processed with an inner concave arc surface, and two opposite inner concave arc surfaces are symmetrically and equidistantly distributed with a plurality of tenon 3, the chuck slot on the chuck and the tenon on the chuck strut The quantity is the same, the tenon 3 is clamped with the chuck groove 2, and the tenon is inserted into the chuck groove 2 when the chuck 1 is installed. There is an expansion wrench 5 on the chuck strut 4, and the expansion wrench 5 is located below the concave arc surface on the chuck strut, and the upper end of the chuck strut is expanded when the chuck 1 and the test piece are installed. The lower end of the chuck strut has a chuck strut external thread 6, the fastening ring 7 is installed on the upper end of the chuck strut 4, and the two sides of the fastening ring 7 are processed with symmetrical screw holes 8, and the fastening bolts 9 are connected with the screw holes. The hole 8 is installed in cooperation, and the upper part of the chuck strut 4 is tightened with the chuck by the fastening bolt 9 .

The water-cooled base includes a backup ring 10, a base 11, a base internal thread 12, a water outlet 13, and a base external thread 14. The base 11 has a penetrating water outlet 13 connected to the water circulation cooling system; The external thread 6 at the lower end of the chuck strut is matched and connected, and is locked by the backup ring 10 . The base bottom has base external thread 14 to be connected with testing machine.

The assembly process of this embodiment

The chuck strut 4 is connected with the base 11 through thread fit, and is locked by the backup ring 10;

Install the collet 1 on the upper end of the collet strut 4 respectively, and install the collet slot 2 and the tenon 3 in cooperation;

An expansion wrench is processed on the chuck strut, and the upper end of the chuck strut is expanded when installing the chuck and the test piece;

The fastening ring 7 is installed on the upper end of the chuck strut 4, and the upper part of the chuck strut 4 is tightened with the chuck by the fastening bolt 9;

Finally, the base 11 is installed on the testing machine, and the water outlet 13 is connected with the water circulation cooling system to complete the assembly.

When using the high temperature and high cycle fatigue test fixture for metal plate samples in this embodiment, the test piece is put into the center of the chuck through the expansion of the expansion wrench 5 on the chuck strut; the screw hole 8 of the fastening ring is aligned with the Apply high-temperature-resistant lubricating oil to the thread of the fastening bolt 9, and tighten the fastening bolt 9 on the fastening ring 7 with a wrench, and then the test can be carried out.

In this embodiment, in order to prevent stress relaxation of the fixture caused by high temperature creep, the chuck 1 , fastening ring 7 , and chuck strut 4 are made of nickel-based superalloy. Guarantee the axial fatigue test of plate-shaped specimens under the test conditions of high temperature environment of up to 1100°C, axial load of up to 600MPa, and frequency range of 90Hz-110Hz, with good reliability and clamping and clamping performance.

Claims (3)

1. a metal plate-like sample Temperature High Cycle Fatigue test fixture, it is characterised in that: include clamp body, water-cooling subbase, folder Specifically being arranged on above water-cooling subbase, water-cooling subbase is fixed on testing machine；Described clamp body includes chuck, chuck strut, tight Gu ring, fastening bolt, described chuck side convex globoidal being evenly equipped with multiple chuck draw-in groove, chuck another side is zigzag, institute Stating chuck strut is cylindrical structure, and chuck strut upper end is machined with inner concave arc surface, and two inner concave arc surfaces are symmetrically distributed with multiple Trip, trip and chuck card slot fit clamping, chuck strut has expansion pull mouth, and expansion is pulled mouth and is positioned at imploded arcs on chuck strut The lower section in face, there is chuck strut external screw thread chuck strut bottom, and described dead ring is arranged on chuck strut upper end, dead ring There is the screw of symmetry at center, two sides, and fastening bolt coordinates with screw and holds out against chuck strut upper end；

Described water-cooling subbase includes standby tight ring, base, and base upper end has base female thread, base bottom to have the outer spiral shell of base Stricture of vagina, has the outlet run through, chuck strut bottom to threaded with base upper end in base, and is locked by standby tight ring, Threadeding with testing machine in base bottom, the outlet of base is connected with hydrologic cycle cooling system.

Metal plate-like sample Temperature High Cycle Fatigue test fixture the most according to claim 1, it is characterised in that: described chuck On chuck draw-in groove identical with the trip quantity on described chuck strut.

Metal plate-like sample Temperature High Cycle Fatigue test fixture the most according to claim 1, it is characterised in that: chuck, tight Gu ring, chuck strut use nickel-base high-temperature alloy material.