Non-destructive characterization of elastic properties on steel plate using laser ultrasound technique under high-temperature atmosphere

The material properties of steel under elevated temperature play a major role in the scientific way and industrial arenas. The calculations of material properties in a precise and fast way help to confirm its structural quality and can avoid the unnecessary damage for its continuous usage. In this present study, a procedure combining laser ultrasound technique (LUT) and back calculation method is followed for non-destructive characterization of elastic properties in steel plate. In LUT, guided acoustic waves are produced to propagate in the steel plate and are measured in non-contact way. By determining the dispersive wave speeds followed by the back calculation procedure, material properties such as Young's modulus and Poisson's ratio of steel plate are characterized in high-temperature environments. Results showed that increasing the temperature reduces Young's modulus. This is due to the reason that the increasing temperature can deteriorate the interatomic bonds in the crystal and initiates dislocations. While increasing the temperature, Poisson's ratio also was increased. Coefficient of thermal expansion has no major effect on Poisson's ratio and Young's modulus. Having the advantages of remote and non-contact mode, the followed laser ultrasound technique shows as an efficient candidate for the measurement of material properties in steel plate under high-temperature atmosphere.