Why Are Video Extensometers Better Suited for High/Low-Temperature and Large-Deformation Testing?

High/low-temperature testing and large-deformation testing are two challenging scenarios in mechanical experiments of materials. The specimen not only experiences complex temperature changes but may also undergo obvious stretching, contraction, necking or even fracture. Traditional contact extensometers often face problems in such environments, including difficult installation, limited range and complex sensor protection.

Haytham video extensometer adopts single-camera DIC vision measurement technology, acquiring specimen deformation data in a non-contact way. During testing, the device needs no specimen clamping; it computes strain and displacement simply by capturing images of marker points or speckle changes on the specimen surface. This approach naturally suits high/low-temperature, large-deformation and complex-condition testing.

Large-deformation measurement of rubber

In high-temperature tests, specimens are usually placed inside a furnace; traditional extensometers need special high-temperature fixtures with high installation and maintenance costs. The video extensometer captures images through the furnace observation window with the device body away from the high-temperature area, improving testing stability and operational safety.

In low-temperature tests, the specimen may be in a low-temperature chamber, liquid nitrogen environment or other special devices, where contact sensors are prone to frosting, space restrictions and temperature shock. The video extensometer completes measurement through long-distance observation, reducing the environment's direct influence on the sensor.

In large-deformation material testing, such as rubber, films, plastics and elastomers, specimens have large deformation ranges and complex fracture patterns. Haythamvideo extensometercontinuously tracks gauge length changes, recording the complete process from initial loading to large deformation, providing richer data for material development, performance evaluation and quality control.

For laboratories that need to balance temperature range, deformation range and testing efficiency, the Haytham video extensometer is a strain measurement tool better suited to complex scenarios.