This paper presents the design of a fiber-coupled self-mixing laser diode (SMLD) for non-contact and non-destructive measurement of Young's modulus. By the presented measuring system, the Young's modulus of aluminum 6061 and brass are measured as 70.0 GPa and 116.7 GPa, respectively, showing a good agreement within the standards in the literature and yielding a much smaller deviation and a higher repeatability compared with traditional tensile testing. Its fiber-coupled characteristics make the system quite easy to be installed in many application cases.
K. Lin, Y. Yu, J. Xi, H. Jun. Li, Q. Guo, J. Tong & L. Su, "A fiber-coupled self-mixing laser diode for the measurement of young's modulus," Sensors, vol. 26, (6) pp. 928-1-928-14, 2016.