Ray trace model of solidification shell thickness non-destructive testing for automatic continuous casting

The significant difference of ultrasonic wave velocity in solid and liquid metal results in ray reflection and refraction and time-of-flight (TOF) delays during propagating through solid-liquid interface. It arouses the interest in making use of the propagation delay to estimate the solidification shell thickness and terminal position of continuous casting slab. In the paper, a ray tracing calculation model was been established to analyze TOF and acoustic intensity of attenuation during propagating along the section of continuous casting slab with liquid-core. Ray paths, wavefront, and TOF which indicates the characteristics of ultrasonic wave that travelling from excitation source to positioned receiver have been simulated completely. Simulation results are consistent with theory calculation. It verified that the ray trace calculation model can provide available data for solidification shell thickness non-destructive testing by ultrasonic technologies.