Clamp for tensile strength test of material

Abstract

The invention discloses a clamp for tensile strength test of a material. The clamp disclosed by the invention comprises a pull rod, a chuck and compressing devices. The pull rod comprises a rod piece, one end of which is connected to a testing device while the other end of which is fixedly connected to a spherical end; the chuck is a bulk member, wherein an open slot which accords with the pull rod in shape is formed in one side of the chuck, and the spherical end can be embedded into the open slot and can drive the rod member to rotate in a small range; an open slot hole which accords with the end part of a test piece in shape is formed in the other side of the chuck, the end part of the test piece is placed in the middle of the open slot hole, and the compressing devices are placed on the upper and lower surfaces and compress the test piece by fastening compression bolts penetrating through bolt holes in the compressing devices and in the open slot hole edge. The clamp disclosed by the invention is simple in structure, convenient to use, high in effectiveness and low in cost, can increase the success rate of the tensile test to a great extent, and is convenient to popularize and use.

Description

technical field [0001] The invention belongs to a test device, in particular to a clamp used for clamping a test piece during a material tensile strength test. Background technique [0002] In the field of combined structures and new materials, material performance tests are often involved, and material performance tests include tensile strength tests of materials. During the tensile strength test, if the material specimen is directly clamped on the material testing machine, due to the characteristics of some materials, it will be found that the end of the specimen is prone to local extrusion damage during the test. The failure of the end leads to the undesired axial tensile failure of the specimen, which leads to the failure of the test. In order to prevent partial pressure failure at the end of the specimen, a reinforcing sheet is attached to the clamping section of the tensile specimen, but this will also cause abnormal effects such as weak bonding, peeling of the clampi...

AI Technical Summary

Problems solved by technology

During the tensile strength test, if the material specimen is directly clamped on the material testing machine, due to the characteristics of some materials, it will be found that the end of the specimen is prone to local extrusion damage during the test. The failure of the end leads to the undesired axial tensile failure of the specimen and the failure of the test

In order to prevent partial pressure damage at the end of the test piece, a reinforcement sheet is pasted on the clamping section of the tensile test piece, but this will also cause abnormal effects such as weak bonding, peeling of the clamping section, and local extrusion damage.

In response to these situations, researchers have designed many fixtures. The common point of these fixtures is that the loading of tensile force is based on the friction force on the surface of the specimen, which is not essentially different from being directly clamped on the material testing machine, or it cannot avoid the end of the specimen. Tensile test failure due to head problems

Images