CN113155592B - Metal material low temperature tensile test device - Google Patents

Abstract

The invention provides a metal material low-temperature tensile test device, which solves the technical problem that the conventional universal and simple low-temperature tensile test device is lacked, and is provided with a heat-insulating barrel, wherein an upper support frame is detachably and fixedly arranged in the heat-insulating barrel, a lower support frame is arranged below the upper support frame, a cavity is arranged at the bottom of the heat-insulating barrel at an interval, and the cavity is provided with a lower support frame descending buffer area and a refrigerant storage area; the upper clamp is arranged on the upper support frame, the lower clamp is arranged on the lower support frame, and the upper clamp and the lower clamp are arranged at an interval in an opposite mode and are respectively used for clamping the upper end and the lower end of a metal sample; the force transfer plate is connected with the guide pillar, the force transfer plate is arranged above the upper support frame, and the guide pillar downwards penetrates through the upper support frame and extends out to be connected with the lower support frame; when the force transmission plate is pressed downwards, the guide pillar drives the lower support frame to enter the lower support frame descending buffer zone downwards, so that the lower clamp is driven to stretch the metal sample downwards, and the device can be widely applied to the field of metal material mechanical property testing.

Description

A low temperature tensile test device for metal materials

technical field

The application belongs to the field of mechanical property testing of metal materials, and particularly relates to a low-temperature tensile test device for metal materials.

Background technique

With the rapid development of modern industries, more and more metal materials need to be used in low-temperature environments, such as low-temperature pressure vessels, bridges, building materials, etc. Therefore, it is necessary to accurately measure the mechanical properties of these materials. It is very important, especially the tensile properties such as yield strength, tensile strength, elongation and area shrinkage of the sample.

At present, the tensile test at room temperature is to directly clamp the metal sample to the chuck of the tensile testing machine for testing, and tighten the screw to clamp the sample. However, since the metal sample is directly tested on the tensile testing machine, it is difficult to ensure the liquid nitrogen conditions required for the low-temperature tensile test, and the tensile testing machine will be damaged. In addition, it is difficult to guarantee the accuracy of the experimental data without using a special ultra-low temperature tensile testing machine for ultra-low temperature experiments. Therefore, for the measurement of mechanical properties of metal materials in low temperature environments, especially tensile tests, due to the limitations of equipment and related conditions, there has been a lack of a general and simple low-temperature tensile test device.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a universal and simple low-temperature tensile test device for metal materials in order to solve the deficiencies of the above-mentioned technologies.

To this end, the present invention provides a low-temperature tensile test device for metal materials, which is provided with a support mechanism, a sample clamping mechanism, and a force transmission guide mechanism; the support mechanism is provided with a heat preservation barrel, an upper support frame, a lower support frame, and a heat preservation barrel It is a barrel-shaped structure with an open upper part, the upper support frame is detachably and fixedly installed in the insulation barrel, the lower support frame is arranged below the upper support frame, and is spaced from the bottom of the insulation barrel with a cavity, and the cavity is provided with The lower support frame descending buffer area and the refrigerant storage area for accommodating refrigerant; the sample clamping mechanism is provided with an upper clamp and a lower clamp, the upper clamp is installed on the upper support frame, the lower clamp is installed on the lower support frame, and the upper clamp It is arranged opposite to the upper and lower clamps, and is used to clamp the upper end and the lower end of the metal sample respectively; the force transmission guide mechanism is provided with a force transmission plate and a guide column connected to each other; the force transmission plate is arranged above the upper support frame, and the guide column It goes down through the upper support frame and extends to connect with the lower support frame; when the force transmission plate is pressed down, the guide column drives the lower support frame down into the lower support frame descending buffer area, thereby driving the lower clamp to stretch down Metal samples.

Preferably, the upper clamp and the lower clamp are respectively provided with a clamping wedge, a clamping cushion and a T-shaped clamping block, the clamping wedge is provided with a semi-open groove, and the clamping cushion is installed in the semi-open groove; T The vertical end of the clamping block is inserted into the semi-open groove, and is set opposite to the clamping pad, and the gap between the two is used to fix and clamp the metal sample; the T-type clamping block and the clamping wedge can be detached and fixed. connect.

Preferably, both the vertical end of the T-shaped clamping block and the contact surface of the clamping spacer for clamping the metal sample are provided with concave-convex patterns, and the two are adapted to occlude the metal sample.

Preferably, both the upper clamp and the lower clamp are fixedly connected to the upper support frame and the lower support frame respectively through the fixing blocks connected thereto.

Preferably, the sample clamping mechanism is further provided with a sample support rod, the sample support rod is arranged between the upper clamp and the lower clamp, the clamping wedge of the lower clamp is provided with a positioning hole, and one end of the sample support rod is connected to the upper clamp. The clamping wedge of the fixture is fixedly connected, and the other end of the sample support rod is inserted into the positioning hole. When the metal sample is stretched, the other end of the sample support rod is separated from the positioning hole.

Preferably, the inner wall of the heat preservation barrel is provided with an annular flange, and the upper support frame is placed on the annular flange.

Preferably, the force transmission guide mechanism is further provided with a transition pressure head, and the transition pressure head is connected and arranged on the upper surface of the force transmission plate.

Preferably, a circular groove is provided on the force transmission plate, and the circular groove is adapted to the bottom of the transition pressure head. When in use, the bottom of the transition pressure head is placed in the circular groove to facilitate transition Positioning of the indenter and the force transfer plate.

Preferably, the upper end of the upper support frame is provided with protruding ears, and the protruding ears extend out of the heat preservation barrel.

Preferably, the outer surface of the thermal insulation barrel is wrapped and connected with a thermal insulation layer.

Preferably, the refrigerant is liquid nitrogen.

The beneficial effects of the invention are as follows: the invention provides a low-temperature tensile testing device for metal materials, which has simple structure, convenient sample disassembly and assembly, good practicability, and can be widely used in various types of universal testing machines. The metal sample will not be deformed by tightening during the installation and stretching process, ensuring that the metal sample is unidirectionally stretched and deformed during the deformation process, and a refrigerant storage area is specially set at the bottom of the insulation barrel to ensure that the sample is deformed. The entire stretching process is carried out under the condition of liquid nitrogen, and there is no situation where the deformation temperature of the metal sample cannot be confirmed.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present application more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only for the present application. In some embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without any creative effort.

Fig. 1 is the structural representation of the perspective view of the present invention;

2 is a schematic structural diagram of a partial cross-sectional view of a front view of the present invention;

Fig. 3 is the structural representation of removing the heat preservation barrel shown in Fig. 1;

Fig. 4 is the structural representation of the heat preservation barrel shown in Fig. 1;

Fig. 5 is the structural schematic diagram of removing the upper support frame shown in Fig. 2;

6 is a schematic structural diagram of the upper clamping assembly, the lower clamping assembly and the sample support rod shown in FIG. 5;

7 is a schematic structural diagram of an exploded view of the lower clamping assembly shown in FIG. 6;

FIG. 8 is a schematic structural diagram of the upper clamping assembly and the lower clamping assembly clamping the metal sample shown in FIG. 6;

FIG. 9 is a schematic view of the structure of the bottom of the sample support rod shown in FIG. 7 inserted into the lower sample clamping end with the cone-shaped structure.

Labels in the picture: 1. Insulation barrel, 2. Upper support frame, 3. Lower support frame, 4. Lower support frame descending buffer zone, 5. Refrigerant storage area, 6. Power transmission plate, 7. Guide post, 8. Metal sample, 9. Clamping wedge, 10. Clamping pad, 11. T-type clamping block, 12. Semi-open groove, 13. Gap, 14. Concave and convex pattern, 15. Fixed block, 16. Sample Support rod, 17. Positioning hole, 18. Ring flange, 19. Transition pressure head, 20. Protruding ears, 21. Insulation layer.

Detailed ways

In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer, the present application will be described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application.

As shown in Figures 1 to 3, the present invention provides a low-temperature tensile test device for metal materials, which is provided with a support mechanism, a sample clamping mechanism, and a force transmission guide mechanism; the support mechanism is provided with a heat preservation barrel 1 and an upper support frame. 2. The lower support frame 3, the heat preservation barrel 1 is a barrel-shaped structure with an open upper part, the upper support frame 2 is detachably and fixedly installed in the heat preservation barrel 1, and the lower support frame 3 is arranged below the upper support frame 2, and is connected with the heat preservation frame 2. The bottom of the barrel 1 is provided with a cavity at intervals, and the cavity is provided with a lower support frame descending buffer area 4 and a refrigerant storage area 5 for accommodating the refrigerant. At the same time, the heat preservation barrel 1 plays a supporting and positioning role for the upper support frame 2; the sample clamping mechanism is provided with an upper clamp and a lower clamp, the upper clamp is installed on the upper support frame 2, and the lower clamp is installed on the lower support frame 3, the upper clamp and the lower clamp are arranged at an upper and lower interval opposite to each other, and are respectively used to clamp the upper end and the lower end of the metal sample 8; the force transmission guide mechanism is provided with a connected force transmission plate 6 and a guide post 7; Above the upper support frame 2, the guide post 7 passes downward through the upper support frame 2 and extends to connect with the lower support frame 3; when the force transmission plate 6 is pressed downward, the guide post 7 drives the lower support frame 3 downward. Enter the descending buffer area 4 of the lower support frame, thereby driving the lower clamp to stretch the metal sample 8 downward.

The above-mentioned upper clamp and lower clamp may be existing devices or the devices disclosed in the present application. As a preferred embodiment, as shown in Fig. 2, Fig. 6, Fig. 7, the upper and lower clamps are arranged opposite to each other at upper and lower intervals, and have the same structure, and are respectively provided with a sample clamping wedge 9, a sample clamping pad 10, and a T-clamp. The sample block 11, the sample clamping wedge 9 is provided with a semi-open groove 12, and the sample clamping pad 10 is installed in the semi-open groove 12; The blocks 10 are arranged opposite to each other, and the gap 13 formed between the vertical end of the T-shaped clamping block 11 and the clamping pad 10 is used to fix and clamp the metal sample 8; the T-shaped clamping block 11 and the clamping wedge 9 are detachable Fixed connection. The upper support frame 2 plays a supporting and positioning role on the clamping wedge 9 of the upper fixture, and the lower supporting frame 3 plays a positioning and supporting role for the clamping wedge 9 of the lower fixture. The surface of the clamping wedge 9 is provided with a semi-open groove 12 to prevent the clamping part of the metal sample 8 from slipping during the stretching process. The clamping method of the metal sample 8 is to place the two ends of the metal sample 8 in the gap 13 of the upper clamp and the lower clamp respectively, and then move the vertical end of the T-type clamp block 11 horizontally to the metal sample 8. , and then cooperate with the clamping block 10 to clamp the metal sample 8 . This clamping method avoids the bending deformation of the metal sample 8 under compression or tensile deformation under tension before the test starts, and maximizes the protection of the metal sample 8 from being twisted during the clamping process, effectively solving the existing problems. When the tensile device clamps the sample, by tightening the clamping method, the technical problem of the torsional deformation caused by the torsion of the sample is unavoidable.

As a more preferred embodiment, as shown in FIG. 7 , the vertical end of the T-shaped clamping block 11 and the contact surface of the clamping spacer 10 for clamping the metal sample 8 are provided with concave-convex patterns 14, and the two are mutually Fits occlusal metal specimen 8. During the stretching process, the clamping of the metal sample 8 is firmer, and it is not easy to slip off.

As a more preferred embodiment, as shown in FIG. 2 and FIG. 3 , the upper clamp and the lower clamp are fixedly connected to the upper support frame 2 and the lower support frame 3 respectively through the fixing blocks 15 connected thereto. The fixing block 15 is used to prevent the T-shaped clamping block 11 from moving during the stretching process.

As a preferred embodiment, as shown in FIG. 2 and FIG. 6 , the sample clamping mechanism is further provided with a sample support rod 16, the sample support rod 16 is arranged between the upper clamp and the lower clamp, and the sample clamping wedge of the lower clamp The block 9 is provided with a positioning hole 17, one end of the sample support rod 16 is fixedly connected with the clamping wedge 9 of the upper fixture, and the other end of the sample support rod 16 is inserted into the positioning hole 17. When the metal sample 8 is stretched, The other end of the sample support rod 16 is separated from the positioning hole 17 . The sample support rod 16 plays the role of supporting and protecting the metal sample 8 and assisting in positioning before the test starts, which can ensure that the metal sample 8 is protected from being twisted during the installation and clamping process. Shear deformation. As a further preferred embodiment, the other end of the sample support rod 16 is a cone-shaped structure, which is convenient to be inserted into the corresponding positioning hole 17 .

As a preferred embodiment, as shown in FIG. 2 and FIG. 4 , the inner wall of the heat preservation barrel 1 is provided with an annular flange 18 , and the upper support frame 2 is placed on the annular flange 18 , thereby further facilitating the removal of the upper support frame 2 put.

As a preferred embodiment, as shown in FIG. 1-FIG. 3, the force transmission guide mechanism is further provided with a transition pressure head 19, which is connected and arranged on the upper surface of the force transmission plate 6, and the external force is transmitted through the transition pressure head 19 to the Power transmission plate 6. Preferably, the lower surface of the transition indenter 19 and the upper surface of the force transmission plate 6 are kept smooth and smooth, and the two planes fit well and will not shake. In order to facilitate the positioning of the transition indenter 19 and the force transmission plate 6, a boss can be processed on the lower bottom surface of the transition indenter 19, a circular groove is machined in the center of the force transmission plate 6, and the boss of the transition indenter 19 is connected to the force transmission plate. The circular groove of the plate 6 accommodates the detachable connection. Before the test begins, the upper support frame 2 sits on the thermal insulation barrel 1 to support the stressed part of the entire tensile test device; during the test, the force transmitted by the transition pressure head 19 is finally borne by the thermal insulation barrel 1 .

As a preferred embodiment, as shown in FIG. 1 and FIG. 2 , the upper end of the upper support frame 2 is provided with protruding ears 20 , and the protruding ears 20 protrude out of the heat preservation bucket 1 , which is convenient for testing operations, and the upper support frame 2 is taken and placed.

As a preferred embodiment, as shown in FIG. 2 , the outer surface of the heat preservation barrel 1 is wrapped and connected with a heat preservation layer 21 . The thermal insulation layer 21 is preferably an asbestos thermal insulation layer 21 , which plays a role in reducing the heat exchange between the inside and outside of the thermal insulation barrel 1 .

As a preferred embodiment, the refrigerant is liquid nitrogen. Liquid nitrogen is inert, colorless, odorless, non-corrosive, non-flammable, and has extremely low temperature. It is an excellent refrigerant. Under normal pressure, the temperature of liquid nitrogen is -196℃.

The invention can be applied to thin metal samples and ultra-low temperature tensile tests of tiny metal samples. Its material is copper silver zirconium alloy.

The working principle of the present invention is as follows: the two ends of the metal sample 8 are respectively clamped in the upper clamp and the lower clamp of the present invention, and then installed in the thermal insulation barrel 1 of the test device, and then liquid nitrogen is injected into the thermal insulation barrel 1 After the temperature in the heat preservation barrel 1 is stabilized, the transition pressure head 19 is pressed downward, and the pressure is successively transmitted to the metal sample 8 through the force transmission plate 6, the guide post 7, the lower support frame 3 and the lower clamp, so that the metal Sample 8 was stretched downwards. After the single tensile test is completed, remove the metal sample 8 after the tensile test is completed, replace it with another metal sample 8, and repeat the above operations to complete the low temperature tensile test of the metal sample 8 under liquid nitrogen conditions.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection of the present application. within the range.

Claims (6)

1. A low-temperature tensile test device for metal materials, which is provided with a support mechanism, a sample clamping mechanism, and a force transmission guide mechanism; the sample clamping mechanism is provided with an upper clamp and a lower clamp, and the upper clamp is connected to the The lower clamps are arranged at opposite intervals up and down, and are respectively used to clamp the upper end and the lower end of the metal sample (8). (3), the heat preservation barrel (1) is a barrel-shaped structure with an open top, the upper support frame (2) is detachably and fixedly installed in the heat preservation barrel (1), and the lower support frame (3) ) is arranged below the upper support frame (2), and is spaced from the bottom of the heat preservation barrel (1) with a cavity, and the cavity is provided with a lower support frame descending buffer zone (4) and is used for accommodating refrigeration A refrigerant storage area (5) for refrigerant; the upper clamp is installed on the upper support frame (2), and the lower clamp is installed on the lower support frame (3); the force transmission guide mechanism is provided with The power transmission plate (6) and the guide column (7) are connected; the force transmission plate (6) is arranged above the upper support frame (2), and the guide column (7) passes downward through the The upper support frame (2) extends out and is connected to the lower support frame (3); when the force transmission plate (6) is pressed downward, the guide post (7) drives the lower support frame (3) ) down into the lower support frame descending buffer area (4), thereby driving the lower clamp to stretch the metal sample (8) downward; The upper clamp and the lower clamp are respectively provided with a clamping wedge (9), a clamping cushion (10), and a T-shaped clamping block (11), and the clamping wedge (9) is provided with a half-shaped clamping block. an open groove (12), the clamping block (10) is installed in the half-open groove (12); the vertical end of the T-shaped clamping block (11) is inserted into the half-open groove (12) , and is arranged opposite to the sample clamping block (10), and the gap (13) between the two is used for fixing and clamping the metal sample (8); the T-shaped clamping block (11) is connected to the The clamping wedge (9) is detachably and fixedly connected; the vertical end of the T-shaped clamping block (11) and the clamping spacer (10) are used to clamp the contact of the metal sample (8). The surfaces are provided with concave-convex patterns (14), and the two are adapted to each other to fix the metal sample (8); the upper clamp and the lower clamp are respectively connected to each other through the fixing blocks (15) connected to them. The upper support frame (2) and the lower support frame (3) are fixedly connected; The sample clamping mechanism is further provided with a sample support rod (16), the sample support rod (16) is arranged between the upper clamp and the lower clamp, and the sample clamping wedge of the lower clamp (9) A positioning hole (17) is provided, one end of the sample support rod (16) is fixedly connected with the clamping wedge (9) of the upper clamp, and the other end of the sample support rod (16) Inserted into the positioning hole (17), when the metal sample (8) is stretched, the other end of the sample support rod (16) is separated from the positioning hole (17). 2 . The low-temperature tensile test device for metal materials according to claim 1 , wherein the inner wall of the heat preservation barrel ( 1 ) is provided with an annular flange ( 18 ), and the upper support frame ( 2 ) is provided with an annular flange ( 18 ). 3 . seated on the annular flange (18). 3 . The low-temperature tensile test device for metal materials according to claim 1 , wherein the force transmission guide mechanism is further provided with a transition indenter ( 19 ), and the transition indenter ( 19 ) is connected to the the upper surface of the force transmission plate (6). 4 . The low-temperature tensile test device for metal materials according to claim 1 , wherein the upper end of the upper support frame ( 2 ) is provided with protruding ears ( 20 ), and the protruding ears ( 20 ) protrude out. 5 . outside the heat preservation barrel (1). 5. A metal material low temperature tensile test device according to claim 1, characterized in that, the outer surface of the heat preservation barrel (1) is wrapped and connected with a heat preservation layer (21). 6 . The low-temperature tensile test device for metal materials according to claim 1 , wherein the refrigerant is liquid nitrogen. 7 .

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