In the testing machine, the extensometer has a close relationship with it. Extensometers can be divided into three types: axial extensometers, transverse extensometers, and clip-on extensometers, as follows:
Extensometers are sensors that sense the deformation of test pieces. Strain gauge extensometers are currently widely used due to their simple principles and easy installation. Extensometers can be divided into axial extensometers, transverse extensometers, and clip-on extensometers according to the measurement object.
Radial extensometer: used to detect radial shrinkage deformation of standard specimens. It is used in conjunction with an axial extensometer to determine Poisson's ratio μ. It converts radial deformation (or deformation in a certain lateral direction) into electrical quantity, and then measures, records or controls another device through a secondary instrument.
Clip-on extensometer: used to detect crack opening displacement. Clip-on extensometer is one of the commonly used instruments in fracture mechanics experiments. It is mostly used in experiments to determine material fracture toughness. ?High precision, easy installation and simple operation. When the specimen breaks, the extensometer can automatically detach from the specimen, which is suitable for static and dynamic deformation measurement.
