Chuck of metal wire torsion testing machine

The utility model relates to a claw-type fixture for metal wire reversing test which overcomes the shortcoming that the existing fixture block has a small interface with the sample which leads to small clamping force, limits sample specification, has a high requirement for the metal wire straightening and even scratches the sample, etc. the technic proposal is that the utility model consists of a clamp (1), a fixture block (2), a fastening nut (3) positioned on the main clamp (1) and a frame (4) fixing the main clamp (1). The main clamp (1) has four fixture blocks (2), one end of each fastening nut (3) is provided with the fixture block (2), the main clamp (1) has a hole (2) and the fastening nut (6) fixes the main clamp (1) and the frame (4) combined with a hole (5). The utility model is characterized in that the fixture has a big clamping interface and a big clamping force, is easy to change the fixture block and is suitable for metal wire clamp with different specification, hardness and strength.