An extensometer is a device that is able to measure the slightest changes in the length of a material at a very high level of accuracy and to record such measurements during mechanical tests. Extensometers are high-accuracy sensors or measurement devices that are connected to the sample during a test. These sensors convert the deformations of the sample – which occur usually in the form of elongation or compression - into electrical, optical or mechanical variables. Extensometers come in various types designed for various applications. For instance, extensometers designed for tensile tests measure the changes in the length of the sample, while those designed for compression tests measure the compression behaviour of the material. These devices help engineers understand the behaviour of the material and improve the safety and performance of products.
