CN102721607A - A deformation measuring device for a boss-free metal material high-temperature tensile test - Google Patents

Abstract

The invention relates to a deformation measuring device for high-temperature tensile test of a metal material without a boss, comprising a spring, an upper scissor device, a lower scissor device, an upper clamp, a lower clamp, an extension rod, a deformation sensor and a high-temperature furnace. Both the upper and lower fixtures are placed in a high-temperature furnace, the upper part of the upper fixture is provided with an upper scissor device, the lower part is fixed with an extension rod, the upper part of the lower fixture is provided with a lower scissor device, and the lower part is fixed with an extension rod; The top of the device is connected by a spring, and extends out of the upper mouth of the high-temperature furnace. The upper and lower clamps firmly hold the sample through the force of the spring; the lower end of the extension rod protrudes from the lower mouth of the high-temperature furnace. Deformation sensors are connected on both sides to form a bilateral measurement system to measure the deformation value of the sample. Compared with the prior art, the present invention can not only measure ordinary non-boss metal material samples such as wires, rods, pipes, etc., but also can measure high-temperature tensile tests of multi-strand special non-boss metal material samples such as steel wire bundles. The deformation value within the timescale.

Description

Deformation measuring device for high temperature tensile test of metal material without boss

technical field

The invention relates to the field of high-temperature tensile mechanical performance testing of metal materials, and is a technology for measuring the deformation within the gauge length when conducting high-temperature tensile tests on metal material samples without bosses such as wires, rods, pipes, and steel wire bundles. device.

Background technique

At present, when conducting high-temperature tensile tests on metal material samples without bosses (such as wires, rods, pipes, etc.) at home and abroad, when using a more accurate method to measure the deformation within the gauge length, the devices used are mostly side-inserted extensions. count. This kind of extensometer can only realize unilateral measurement of sample deformation, so that the sample deformation measurement is greatly affected by the load eccentricity caused by the different axis of the testing machine, and the measurement accuracy is not high enough; its measuring range is limited, and the gauge length is less than 50mm ; Because most of them are imported products, they are expensive. In addition, this kind of extensometer is mainly suitable for a single sample. For special multi-strand metal material samples without bosses such as steel strands and steel wire bundles, it can only measure the high-temperature deformation of the outer steel wires, but cannot measure The amount of deformation of the entire sample is difficult to apply.

Contents of the invention

The object of the present invention is to provide a deformation measuring device with a wide application range, capable of bilateral measurement, and suitable for high temperature tensile tests of metal materials without bosses, in order to overcome the deficiencies in the prior art.

Technical scheme of the present invention is:

A deformation measuring device for high-temperature tensile tests on metal materials without bosses, characterized in that it includes a spring, an upper scissor device, a lower scissor device, an upper clamp, a lower clamp, an extension rod, a deformation sensor, and a high-temperature furnace. The upper and lower fixtures are placed in a high-temperature furnace, the upper part of the upper fixture is provided with an upper scissor device, the lower part is fixed with an extension rod, the upper part of the lower fixture is provided with a lower scissor device, and the lower part is fixed with an extension rod; the upper scissor device, the lower The top of the scissor device is connected by a spring, and extends out of the upper opening of the high-temperature furnace. The upper and lower clamps firmly hold the sample through the force of the spring. The lower end of the extension rod protrudes from the lower opening of the high-temperature furnace. Deformation sensors are connected to both symmetrical sides of the sample to form a bilateral measurement system to measure the deformation value of the sample.

The upper fixture includes two splints clamping opposite sides of the sample, one end of the two splints is fixedly connected together, and the other end is respectively connected to an upper scissor device.

The upper scissors device includes two scissor-type hinged pull rods, one end of the two pull rods is connected to the upper clamp, and the other end is connected to each other through a spring. The elastic force of the spring makes the two splints of the upper clamp become longer when the sample is stretched. During the thinning process, it advances evenly, and always firmly clamps the sample.

The lower clamp includes two splints clamping opposite sides of the sample, one end of the two splints is fixedly connected together, and the other end is respectively connected to the lower scissor device.

The lower scissors device includes two scissor-type hinged pull rods, one end of the two pull rods is connected to the lower clamp, and the other end is connected to each other through a spring. The elastic force of the spring makes the two splints of the lower clamp become longer when the sample is stretched, During the thinning process, it advances evenly, and always firmly clamps the sample.

The extension rods include four, two are fixed at the lower part of the upper clamp, two are fixed at the lower part of the lower clamp, and the lower ends of the four extension rods are arranged on the guide block to ensure that the axis of the extension rod is parallel to the axis of the sample.

The deformation sensor is a differential transformer type displacement sensor, two in total, installed symmetrically on both sides of the sample, each deformation sensor is connected to two extension rods to form a bilateral measurement system to measure the distance between the upper clamp and the lower clamp. The relative displacement can be used to obtain the high temperature deformation value of the sample.

The beneficial effects of the device of the present invention are: compared with the prior art, the device of the present invention can not only solve common non-bossed metal material samples such as wires (such as steel wires), rods, pipes, etc. The deformation measurement problem of the multi-strand special non-boss metal material sample in the high temperature tensile test, the applicable temperature range of this device is 0 ~ 1000 ℃, and it can measure the deformation of the sample in the whole process from elastic deformation to fracture It can achieve bilateral measurement, avoid the influence of eccentric stretching caused by unilateral measurement, improve the measurement accuracy, and the cost is much cheaper than imported side-inserted unilateral extensometers. The device of the invention completely tests the relevant mechanical properties of a single metal material sample such as a steel wire and a special multi-strand metal material sample such as a steel wire bundle under high temperature stretching.

Description of drawings

Fig. 1 is the structural representation of device longitudinal section of the present invention;

Fig. 2 is the structural representation of another direction longitudinal section of device of the present invention;

Fig. 3 is the plane structural representation of device of the present invention;

In the figure: 1- metal material sample, 2- spring, 3- upper scissor device, 4- lower scissor device, 5- upper clamp, 6- lower clamp, 7- extension rod a, 8- extension rod b, 9-extension rod c, 10-extension rod d, 11-high temperature furnace, 12-guide block, 13-differential transformer displacement sensor a, 14-differential transformer displacement sensor b.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example 1

As shown in Figures 1 to 3, a deformation measuring device for high-temperature tensile tests of metal materials without bosses, including a spring 2, an upper scissor device 3, a lower scissor device 4, an upper clamp 5, a lower clamp 6, and an extension rod a7, extension rod b8, extension rod c9, extension rod d10, high temperature furnace 11, guide block 12, differential transformer displacement sensor a13, differential transformer displacement sensor b14.

When in use, first clamp the metal material sample 1 with the upper and lower clamps of the tensile testing machine, and then fix the two splints of the upper fixture 5 to the upper gauge end of the sample according to the determined sample gauge length. One end is fixedly connected together, and the other end is respectively connected to the upper scissor device 3. The tops of the two scissor-type hinged pull rods of the upper scissor device 3 stretch out from the top of the high-temperature furnace 11, and are connected to each other by the spring 2. The elastic force of the spring makes the two The two splints move in evenly during the process of the sample becoming longer and thinner, and always hold the sample firmly.

In the same way, fix the two splints of the lower fixture 6 to the lower gauge end of the sample, one end of the two splints is fixedly connected together, and the other end is respectively connected to the lower scissor device 4, and the two scissors of the lower scissor device 4 are connected to each other. The top end of the hinged rod protrudes from the top of the high-temperature furnace 11 and is connected by a spring 2. The elastic force of the spring makes the two splints move inward evenly during the process of the sample becoming longer and thinner, and firmly clamp the sample all the time.

The lower part of the upper fixture 5 is connected with two extension rods: extension rod a7 and extension rod c9, the lower part of the lower fixture 6 is connected with two extension rods: extension rod b8 and extension rod d10, and the lower ends of the four extension rods protrude from the lower opening of the high temperature furnace 11. Set it on the guide block 12 and adjust it to be straight. The lower end of the extension rod a7 and the extension rod b8 is connected to the differential transformer type displacement sensor a13, and the lower end of the extension rod c9 and the extension rod d10 is connected to the differential transformer type displacement sensor b14. The symmetrical two sides form a bilateral measurement system. During the high temperature tensile test, the differential transformer displacement sensor a13 and the differential transformer displacement sensor b14 can respectively measure the relative position of the sample between the upper clamp 5 and the lower clamp 6. Displacement, the average value of the two sets of data is used as the high-temperature deformation in the gauge length section of the sample.

Claims (7)

1. A deformation measuring device for high-temperature tensile test of a metal material without a boss, is characterized in that it comprises a spring, an upper scissor device, a lower scissor device, an upper clamp, a lower clamp, an extension rod, a deformation sensor, a high-temperature furnace, Both the upper and lower clamps are placed in a high-temperature furnace, the upper part of the upper clamp is provided with an upper scissor device, the lower part is fixed with an extension rod, the upper part of the lower clamp is provided with a lower scissor device, and the lower part is fixed with an extension rod; the upper scissor device The top of the lower scissor device is connected by a spring, and extends out of the upper opening of the high-temperature furnace. The upper and lower clamps firmly hold the sample through the force of the spring, and the lower end of the extension rod protrudes from the lower opening of the high-temperature furnace. , connecting deformation sensors on both symmetrical sides of the sample to form a bilateral measurement system to measure the deformation value of the sample. 2. The deformation measuring device for a high-temperature tensile test of a metal material without a boss according to claim 1, wherein the upper clamp includes two splints for clamping the opposite sides of the sample, and one end of the two splints is They are fixedly connected together, and the other ends are respectively connected to the upper scissor device. 3. A deformation measuring device for high-temperature tensile tests of metal materials without bosses according to claim 1 or 2, wherein the upper scissor device comprises two scissor-type hinged pull rods, two pull rods One end is connected to the upper fixture, and the other end is connected to each other through a spring. The elastic force of the spring makes the two splints of the upper fixture move in evenly during the stretching process of the sample to become longer and thinner, and always hold the sample firmly. 4. The deformation measuring device for a high-temperature tensile test of a metal material without a boss according to claim 1, wherein the lower clamp includes two splints clamping opposite sides of the sample, and one end of the two splints is They are fixedly connected together, and the other ends are respectively connected to the downward scissor device. 5. A deformation measuring device for high-temperature tensile tests of metal materials without bosses according to claim 1 or 4, wherein said lower scissor device comprises two scissor-type hinged pull rods, two pull rods One end is connected to the lower fixture, and the other end is connected to each other through a spring. The elastic force of the spring makes the two splints of the lower fixture move inward evenly during the stretching process of the sample to become longer and thinner, and always hold the sample firmly. 6. The deformation measuring device for a high-temperature tensile test of a metal material without a boss according to claim 1, wherein said extension rods comprise four, two are fixed at the bottom of the upper clamp, and two are fixed at the bottom of the lower clamp. The lower ends of the four extension rods are set on the guide block to ensure that the axis of the extension rod is parallel to the axis of the sample. 7. The deformation measuring device for a high-temperature tensile test of a metal material without a boss according to claim 1, wherein the deformation sensor is a differential transformer type displacement sensor, and there are two of them symmetrically installed on the test surface. On both sides of the sample, each deformation sensor is connected to two extension rods to form a bilateral measurement system to measure the relative displacement between the upper and lower clamps to obtain the high-temperature deformation value of the sample.

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