Young's modulus measurement using fibre-coupled self-mixing laser diode

A new fibre-coupled self-mixing laser diode is developed for measurement of Young's modulus. Instead of transmission in free space, the light path is coupled in a fibre, which enables the measuring system easily and feasibly to be installed in many application cases. A specimen made of aluminium alloy 6061 is tested by the system designed. The obtained value of Young's modulus is 70.02 GPa with 0.16% measurement accuracy, showing a high repeatability and a good agreement with the standard values reported in literatures.